iWorX CCU1 Application Manual

1 Application Guide 505-022 CCU1 Chiller Controller Self-Contained Interoperable Controller Model UCP-1 SUPERSEDES: September 1, 2010 EFFECTIVE: September 23, 2010 Table of Contents CCU1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Purpose of This Guide . . . . . . . . . . . . . . . . . . . . . . . . . 3 Representations and Warranties . . . . . . . . . . . . . . . . . 3 Applicable Documentation . . . . . . . . . . . . . . . . . . . . . . 4 Installation Instructions. . . . . . . . . . . . . . . . . . . . . . . . . 5 Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Static Electricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 FCC Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Before Installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 About this Document . . . . . . . . . . . . . . . . . . . . . . . . 5 Inspecting the Equipment . . . . . . . . . . . . . . . . . . . . 6 What is Not Included with this Equipment . . . . . . . . 6 Equipment Location . . . . . . . . . . . . . . . . . . . . . . . . . 6 Selecting a Power Source . . . . . . . . . . . . . . . . . . . . 6 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Mounting the Device . . . . . . . . . . . . . . . . . . . . . . . . 6 Routing Cabling to the Device . . . . . . . . . . . . . . . . . 7 Grounding the Device . . . . . . . . . . . . . . . . . . . . . . . 7 Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Connecting Input Devices . . . . . . . . . . . . . . . . . . . 10 Connecting Output Devices . . . . . . . . . . . . . . . . . . 11 Other Connections . . . . . . . . . . . . . . . . . . . . . . . . . 11 Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Application Description. . . . . . . . . . . . . . . . . . . . . . . . . 14 Sequence of Operation . . . . . . . . . . . . . . . . . . . . . . . . 16 Chiller Activation . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Chiller Setpoint Adjustment . . . . . . . . . . . . . . . . . . 16 Chiller Pump Control . . . . . . . . . . . . . . . . . . . . . . . 16 Condenser Pump Control . . . . . . . . . . . . . . . . . . . 16 Cooling Tower Bypass Valve Control . . . . . . . . . . 16 Cooling Tower Variable Speed Fan Control . . . . . 17 Chiller Low Limit Control . . . . . . . . . . . . . . . . . . . . 17 Chiller Alarm Status. . . . . . . . . . . . . . . . . . . . . . . . 18 Runtime Accumulations. . . . . . . . . . . . . . . . . . . . . 18 Alarms and Events . . . . . . . . . . . . . . . . . . . . . . . . 18 Automatic Configuration . . . . . . . . . . . . . . . . . . . . 19 Networking Controllers . . . . . . . . . . . . . . . . . . . . . 19 Controller Identification . . . . . . . . . . . . . . . . . . . . . . . . 20 Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 All Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Diagnostic LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Troubleshooting Tips . . . . . . . . . . . . . . . . . . . . . . . 26

© 2010 Taco Electronic Solutions, Inc. THIS PAGE LEFT BLANK INTENTIONALLY

3 © 2010 Taco Electronic Solutions, Inc. CCU1 The iWorX CCU1 chiller controller is a stand-alone microprocessor based controller for supervisory central chiller con- trol applications that utilize one air-cooled chiller or a water-cooled centrifugal chiller with cooling tower. Overview Analog inputs are provided for chiller water supply temperature, chiller water return temperature, condenser water sup- ply temperature, and condenser water return temperature. Digital inputs are provided for chiller pump flow proof, con- denser pump flow proof, a cooling water demand proof, and a chiller general alarm. The CCU1 incorporates digital outputs in the form of triacs for chiller low limit status and the start and stop of the chiller and condenser pumps. In addition, three analog outputs are provided to control a modulated bypass valve, a variable speed fan, and set the adjustable setpoint of the chiller. The controller is based on the LONWORKS® networking technology. The controller can be networked to a higher-level control system for monitoring and control applications, and provides chilled water in response to demand from other controllers. Features • Adjustable chiller setpoint • Modulated cooling tower bypass valve • Modulated cooling tower fan • Minimum cycle timers for chiller On and Off • Runtime accumulation for chiller, pumps, and fan • Lead/Lag operation of water pumps • Maximum of 60 cooling zones • Proportional + Integral (P+I) control of the modulated bypass valve • Proportional + Integral (P+I) control of a variable speed fan • OAT low limit protection • Flow proof inputs • Chiller enable/demand input • Chiller alarm input • Automatic configuration with the LCI • Alarm/Event reporting PURPOSE OF THIS GUIDE The iWorX CCU1 Application Guide provides application information for the CCU1 Controller. The reader should understand basic HVAC concepts, intelligent environmental control automation, and basic LON- WORKS networking and communications. This Application Manual is written for: • Users who engineer control logic • Users who set up hardware configuration • Users who change hardware or control logic • Technicians and field engineers REPRESENTATIONS AND WARRANTIES This Document is subject to change from time to time at the sole discretion of Taco Electronic Solutions, Inc. All updates to the Document are available at www.taco-hvac.com. When installing this product, it is the reader’s responsi- bility to ensure that the latest version of the Document is being used.

© 2010 Taco Electronic Solutions, Inc. The iWorX CCU1 shall only be used for the applications identified in the product specifications and for no other pur- poses. For example, the iWorX CCU1 is not intended for use to support fire suppression systems, life support systems, critical care applications, commercial aviation, nuclear facilities or any other applications where product failure could lead to injury to person, loss of life, or catastrophic property damage and should not be used for such purposes. Taco Electronic Solutions, Inc. will not be responsible for any product or part not installed or operated in conformity with the Document and instructions or which has been subject to accident, disaster, neglect, misuse, misapplication, inade- quate operating environment, repair, attempted repair, modification or alteration, or other abuse. For further informa- tion, please refer to the last page of this Document for the company’s Limited Warranty Statement, which is also issued with the product or available at www.taco-hvac.com. APPLICABLE DOCUMENTATION Table 1: Applicable Documentation Description Audience Purpose iWorX CCU1 Application Guide, Document No. 505-022 (this docu- ment) – Application Engineers – Wholesalers – Contractors – Start-up Technicians – End user Provides instructions for setting up and using the iWorX CCU1 Controller. iWorX LCI2 Application Guide, Doc- ument No. 505-002 – Application Engineers – Installers – Service Personnel – Start-up Technicians – End user Provides instructions for setting up and using the iWorX Local Control Interface. iWorX DXU3 Application Guide, Document No. 505-004 – Application Engineers – Installers – Service Personnel – Start-up Technicians – End user Provides instructions for setting up and using the iWorX Con- troller. iWorX DXU4 Application Guide, Document No. 505-005 – Application Engineers – Installers – Service Personnel – Start-up Technicians – End user Provides instructions for setting up and using the iWorX DXU4 Controller. http://iWorxWizard.taco-hvac.com – Application Engineers – Wholesalers – Contractors An on-line configuration and submittal package generator based on user input. Automatically generates bill of materials, sequence of operations, flow diagrams, wiring diagrams, points and specifications. Additional Documentation LonWorks FTT-10A Free Topology Transceiver User’s Guide, published by Echelon Cor- poration. It provides specifications and user instructions for the FTT-10A Free Topology Transceiver. See also: www.echelon.com/support/documentation/manuals/transceivers.

5 © 2010 Taco Electronic Solutions, Inc. INSTALLATION INSTRUCTIONS Precautions General This symbol is intended to alert the user to the presence of important installation and maintenance (servic- ing) instructions in the literature accompanying the equipment. WARNING: Electrical shock hazard. Disconnect ALL power sources when installing or servicing this equipment to prevent electrical shock or equipment damage. Make all wiring connections in accordance with these instructions and in accordance with pertinent national and local electrical codes. Use only copper conductors. Static Electricity Static charges produce voltages that can damage this equipment. Follow these static electricity precautions when han- dling this equipment. • Work in a static free area. • Touch a known, securely grounded object to discharge any charge you may have accumulated. • Use a wrist strap when handling printed circuit boards. The strap must be secured to earth ground. Location Avoid locations where corrosive fumes, excessive moisture, vibration or explosive vapors are present. Avoid electrical noise interference. Do not install near large contactors, electrical machinery, or welding equipment. This equipment is suitable for indoor or outdoor use. Preferably, or as required by National Electrical Code, the unit is intended to be installed within an electrical control enclosure. Operate where ambient temperatures do not exceed 140 °F (60 °C) or fall below 32 °F (0 °C) and relative humidity does not exceed 90%, non-condensing. FCC Compliance This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference. This equip- ment can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a par- ticular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: • Reorient or relocate the receiving antenna. • Increase the separation between the equipment and the receiver. • Connect the equipment to a power source different from that to which the receiver is connected. • Consult the equipment supplier or an experienced radio/TV technician for help. You are cautioned that any changes or modifications to this equipment not expressly approved in these instructions could void your authority to operate this equipment in the United States. BEFORE INSTALLING About this Document The instructions in this manual are for the CCU1 module, which supports one central plant consisting of one air-cooled chiller or one water-cooled chiller with cooling tower.

© 2010 Taco Electronic Solutions, Inc. Inspecting the Equipment Inspect the shipping carton for damage. If damaged, notify the carrier immediately. Inspect the equipment for damage. Return damaged equipment to the supplier. What is Not Included with this Equipment • A power source for the equipment electronics and peripheral devices. • Tools necessary to install, troubleshoot and service the equipment. • The screws or DIN rail needed to mount the device. • Peripheral devices, such as sensors, actuators, etc. • Cabling, cabling raceway, and fittings necessary to connect this equipment to the power source, FTT-10A network and peripheral devices. Equipment Location Abide by all warnings regarding equipment location provided earlier in this document. Optimally, the equipment should be installed within a secure enclosure. If the equipment is to be installed outdoors, it must be contained within a protective enclosure. The enclosure must maintain internal temperature and humidity within the ranges specified for this equipment. The equipment must be installed within 500 feet of all input peripherals (smoke detectors, sensors, etc.) that will be connected to the equipment. Selecting a Power Source This equipment requires a UL recognized Class 2 external power source (not supplied) to operate. The controller power input requires a voltage of 24 Volts AC. To calculate power source current requirements, add the power consumption of all peripheral devices to that of the controller. The controller and triac output loads can use the same power source. If both are using the same power source, the loads must have EMF protection. This protection can be integral to the load, or installed in the 24 VAC wiring across the load’s coil. To provide necessary RFI and transient protection, the controller’s ground (GND) pin (T40) must be connected to earth ground or the earth ground of the packaged unit’s enclosure ground. Failure to properly ground the controller may cause it to exceed FCC limits. Excessive noise could also produce inaccurate sensor data. The power source must be capable of operating with this connection to ground. INSTALLATION Warning: Electrical shock hazard. To prevent electrical shock or equipment damage, disconnect ALL power sources to controllers and loads before installing or servicing this equipment or modifying any wir- ing. Mounting the Device 1.Select a mounting location. Enclosure mounting is recommended. 2.Hold the controller on the panel you wish to mount it on. With a marker or pencil mark the mounting locations on the panel. 3.Using a small drill bit pre-drill the mounting holes. 4.Using two #6 pan head screws, mount the controller to the panel. 5.Wire the controller (See Routing Cabling to the Device).

7 © 2010 Taco Electronic Solutions, Inc. Figure 1: Mounting Dimensions Routing Cabling to the Device Cabling used to connect the power source and cabling used to connect the FTT-10A network must remain separated within the control enclosure and wiring conduit. Grounding the Device The ground terminal (T40) must be securely connected to earth ground. Failure to properly ground this equipment will result in improper operation. Improper grounding may also increase the risk of electrical shock and may increase the possibility of interference with radio/TV reception. For best performance, connect the power supply common terminal (T38) to the same external point as the ground terminal (T40).

© 2010 Taco Electronic Solutions, Inc. WIRING INFORMATION WARNING: Terminals 6, 9, 12, 15, 18, 33, 36, and 38 are connected internally on all CCU1 controllers. Disconnect ALL power sources when installing or servicing this equipment to prevent electrical shock or equipment damage. Figure 2: Wiring Diagram for Power Sourcing applications

9 © 2010 Taco Electronic Solutions, Inc. Figure 3: Wiring Diagram for Power Sinking applications

© 2010 Taco Electronic Solutions, Inc. Figure 4: Wiring Diagram for Power Isolated applications Connecting Input Devices Chiller Water Supply Temperature (CWS) To connect the chiller water supply thermistor to the unit, attach one wire from the thermistor to CWS (T19) and the other wire to the adjacent common (T18). The thermistor used must be a 10K Precon Type III. Chiller Water Return Temperature (CWR) To connect the chiller water return thermistor to the unit, attach one wire from the thermistor to CWR (T17) and the other wire to the adjacent common (T18). The thermistor used must be a 10K Precon Type III. Condenser Supply Temperature (CDS) To connect the condenser water supply thermistor to the unit, attach one wire from the thermistor to CDS (T16) and the other wire to the adjacent common (T15). The thermistor used must be a 10K Precon Type III. Condenser Return Temperature (CDR) To connect the condenser water return thermistor to the unit, attach one wire from the thermistor to CDR (T14) and the other wire to the adjacent common (T15). The thermistor used must be a 10K Precon Type III.

11 © 2010 Taco Electronic Solutions, Inc. Chiller Flow Proof (CFP) To connect the chiller flow proof switch to the digital input, attach one wire of the contact to CFP (T13) and the other wire to the adjacent common (T12). This must be a dry contact, normally open switch which closes when flow is detected. If a flow proof switch is not installed, the terminals should be connected with a jumper wire. Condenser Flow Proof (CDFP) To connect the condenser flow proof switch to the digital input, attach one wire of the contact to CDFP (T11) and the other wire to the adjacent common (T12). This must be a dry contact, normally open switch which closes when flow is detected. If a flow proof switch is not installed, the terminals should be connected with a jumper wire. Chiller General Alarm (ALM) To connect the chiller’s general alarm output to the digital input, attach one wire of the contact to ALM (T5) and the other wire to the adjacent common (T6). This output from the chiller must act as a dry contact, normally open switch. Chilled Water Demand (CWD) To connect the demand switch to the digital input, attach one wire of the contact to CWD (T8) and the other wire to the adjacent common (T9). This must be a dry contact, normally open switch. Connecting Output Devices Chiller Pumps 1 & 2 (CHP1, CHP2) The outputs for the pumps must be connected to 24 VAC pilot relays if the load is greater than 1 Amp for each pump. If the load is less than 1 Amp, connect pump 1 to CHP1 (T31) and TC12 (T30), and connect pump 2 to CHP2 (T29) and TC12 (T30). Condenser Pumps 1 & 2 (CDP1, CDP2) The outputs for the pumps must be connected to 24 VAC pilot relays if the load is greater than 1 Amp for each pump. If the load is less than 1 Amp, connect pump 1 to CDP1 (T28) and TC34 (T27), and connect pump 2 to CDP2 (T26) and TC34 (T27). Chiller Low Limit (CLL) The output for the chiller low limit interface must be connected to a 24 VAC pilot relays if the load is greater than 1 Amp. If the load is less than 1 Amp, connect the chiller's low limit input to CLL (T25) and TC56 (T24). Chiller Setpoint Adjustment (CSP) The chiller setpoint adjustment output can be set to 0-10 VDC max through the control logic. Connect the positive wire from the chiller’s setpoint adjustment input to CSP (T37) and the other wire to the adjacent common (T36). Cooling Tower Valve (CTV) The cooling tower bypass valve output can be set to 0-10 VDC max through the control logic. Connect the positive wire from the valve actuator to CTV (T35) and the other wire to the adjacent common (T36). Cooling Tower Fan (CTF) The cooling tower fan output can be set to 0-10 VDC max through the control logic. Connect the positive wire from the fan actuator to CTF (T34) and the other wire to the adjacent common (T33). Other Connections Network (LON) Network wiring must be twisted pair. One network wire must be connected to terminal NETA (T1) and the other network wire must be connected to terminal NETB (T2). Polarity is not an issue since an FTT-10A network is used for commu- nications. Power (PWR) Connect one output wire from a 24 VAC power supply to PWR (T39) and the other output wire from the power supply to the adjacent common terminal (T38).

© 2010 Taco Electronic Solutions, Inc. Ground (GND) Terminal GND (T40) must be connected to earth ground. Failure to properly ground this equipment will result in improper operation. Improper grounding may also increase the risk of electrical shock, and may increase the possibility of interference with radio and TV reception. SPECIFICATIONS Electrical Inputs • Cabling: twisted shielded pair, 18 AWG recommended—500 feet max. (152 meters) • Resolution: 10 bit Chiller Supply Temperature, Chiller Return Temperature, Condenser Supply Temperature, Condenser Return Temperature • Precon Type III 10K thermistor Chiller Alarm, Chilled Water Demand, Chiller Flow Proof, Condenser Flow Proof • Dry Contact • Normally Open • 5 Volts DC Max Outputs Chiller Pumps 1 & 2, Condenser Pumps 1 & 2, Chiller Low Limit • 24 Volts AC • 1A @ 50C, 0.5A @ 60C, limited by the Class 2 supply rating Chiller Setpoint, Cooling Tower Valve, Cooling Tower Fan • 0-10 Volts DC • 2K Ohm minimum load • 8 bit resolution Recommended Sensor Wire FTT-10A Network • Speed: 78KBPS • Cabling: Maximum node-to-node distance: 1312 feet (400 meters) • Maximum total distance: 1640 feet (500 meters) For detailed specifications, refer to the FTT-10A Free-Topology Transceiver User’s Guide published by Echelon Corpo- ration (www.echelon.com/support/documentation/manuals/transceivers). Power Power Requirements • 24VAC (20VAC to 28VAC), requires an external Class 2 supply Power Consumption • 7.2W with no external loads, maximum limited by the Class 2 supply rating Cable Type Pairs Details Taco Catalog No. 18AWG 1 Stranded Twisted Shielded Pair, Plenum WIR-018 Cable Type Pairs Details Taco Catalog No. Level 4 22AWG (0.65mm) 1 Unshielded, Plenum, U.L. Type CMP WIR-022

13 © 2010 Taco Electronic Solutions, Inc. Mechanical Housing • Dimensions: 5.55” (141mm) high, 6.54” (166 mm) wide, 1.75” deep (44 mm) • ABS Weight • Controller Weight: 0.70 pounds (0.32 kilograms) • Shipping Weight: 1.0 pounds (0.46 kilograms) Electronics • Processor: 3150 Neuron 10 MHz • Flash: 48 Kilobytes • SRAM: 8 Kilobytes • Termination: 0.197” (5.0 mm) Pluggable Terminal Blocks, 14-22 AWG Environmental • Temperature: 32 °F to 140 °F (0 °C to 60 °C) • Humidity: 0 to 90%, non-condensing Agency Listings • UL Listed for US and Canada, Energy Management Equipment PAZX and PAZX7. Agency Compliances • FCC Part 15 Class A

© 2010 Taco Electronic Solutions, Inc. APPLICATION DESCRIPTION The CCU1 chiller controller is a stand-alone microprocessor-based controller for supervisory control of central chiller applications that utilize either an air-cooled chiller or a water-cooled centrifugal chiller with a cooling tower. Two chilled water pumps are configured for lead/lag operation. The CCU1 provides setpoint adjustment control of the chiller by integrating to the factory mounted chiller controls with a 0-10 VDC setpoint control signal. For chilled water plant appli- cations that utilize a cooling tower, the CCU1 controller provides control of the tower bypass valve and two cooling tower (condenser) pumps configured in a lead/lag configuration. Outputs are provided for control of the cooling tower bypass valve. Analog outputs are provided to support cooling tower applications with variable fan speed control. Figure 5: CCU1 Condenser Tower Evaporator LOAD DP DP Chiller General Alarm Chiller Return Temp. Condenser Return Temp. Chiller Supply Temp. Chiller Flow Proof Condenser Flow Proof Condenser. Supply Temp. Chiller Pump 1 Chiller Pump 2 Chiller Setpt. Chiller Low Limit Cooling Tower Valve Cooling Tower Fan Condenser Pump 1 Condenser Pump 2 with cooling tower CCU1 control starts only if there is a cooling water demand and the outside air temperature (OAT) is above the OAT limits --> Cutoff temp. The CCU1 operates in conjunction with up to 60 controllers that can require chilled water (FCU Series, DXU Series, HPU Series). The cooling water demand is obtained by the CCU1 from controllers that have been grouped with the CCU1 at the LCI user interface during initial configuration. Cooling water demand can also be com- municated through a digital input switch, or through a demand for chiller activation from the LCI. Initial chiller control activates a chiller pump. The factory-installed chiller controls, as provided by the chiller manufac- turer, detect water flow in the chilled water loop and activate the chiller. An anti-cycle function provides configurable chiller minimum On and Off times. The CCU1 includes support for two chilled water pumps, with only one pump required for normal operation. One of the pumps is designated the lead pump, with the lag pump only being required in the event of a lead pump alarm. Each time the chiller is deactivated, the lead pump designation is transferred to the other pump.

15 © 2010 Taco Electronic Solutions, Inc. When the chiller is activated, the lead chiller pump is started. If the chiller pump has been commanded on for at least 20 seconds and the Chiller Flow proof is off, an alarm is initiated and the lag pump is started. The lag pump also trig- gers an alarm if it has been commanded on for 20 seconds and flow proof is not established. If both chiller pumps fail, all outputs are turned off, all control stops, and a dual pump failure alarm is generated. Manual reset of the CCU1 con- troller from the operator interface or by cycling power to the CCU1 is required to restart control. The CCU1 also includes support for two condenser water pumps, with only one pump required for normal operation. One of the pumps is designated the lead pump, with the lag pump only being required in the event of a lead pump fail- ure. Each time the system is deactivated, the lead pump designation is transferred to the other pump. In a water-cooled chiller, when the chiller water pump is started the lead condenser pump is started also. If the con- denser pump has been commanded on for at least 20 seconds and the condenser flow proof is off, an alarm is initiated and the lag pump is started. The lag pump also triggers an alarm if it has been commanded on for 20 seconds and flow proof is not established. If both condenser pumps fail, all outputs are turned off, all control stops, and a dual pump fail- ure alarm is generated. Manual reset of the CCU1 controller from the operator interface or by cycling power to the CCU1 is required to restart control. An analog output is provided for setpoint adjustment utilizing the factory-mounted chiller controls. The chiller setpoint adjust feature of the CCU1 enables the user to change the chiller water supply setpoint through the LCI. The bypass valve position is calculated by a Proportional + Integral (P+I) control loop based on the condenser water return temperature and the condenser water setpoint. The bypass valve control loop is activated 15 seconds after the condenser water flow proof has confirmed flow. As the temperature increases above the condenser water setpoint, the bypass valve is modulated open. The bypass valve is modulated closed as the water temperature decreases below the condenser setpoint. The cooling tower bypass valve control loop is selectable for direct or reverse acting operation. The cooling tower fan speed is calculated by a P+I control loop based on the condenser water return temperature and the cooling tower water setpoint. The fan speed control loop is activated 15 seconds after the cooling tower bypass valve has modulated to its 100% position (full flow through tower). As the temperature increases above the cooling tower water setpoint, the fan speed is increased. The fan speed is decreased as the water temperature decreases below the cooling tower setpoint. The fan speed control loop is selectable for direct or reverse acting operation. The CCU1 provides low limit control. When the outside air temperature (OAT) drops below the low limit setpoint as sensed by an ASM controller on the system network, the chiller water pump energizes and the chiller low limit output is enabled. The chiller low limit output is interfaced to the factory supplied chiller controls to signal the chiller to not start in response to the chiller water pump operation during the low limit condition. The chiller water pump and chiller low limit output de-energizes when the temperature rises 1 °F above the low limit setpoint. A digital input is provided on the CCU1 to monitor the status of the chiller's general alarm. An alarm is reported to the LCI when the chiller reports a general alarm condition. The CCU1 monitors the runtime of all four pumps, the chiller, and the fan. When any one of the runtimes exceeds a programmable limit, a maintenance alarm is reported to the LCI. When the water temperatures exceed a programmable limit, a high limit alarm is reported to the LCI. When the water temperature drops below a programmable limit, a low limit alarm is reported to the LCI. When the water temperature returns to the proper range, a return to normal is generated.

© 2010 Taco Electronic Solutions, Inc. SEQUENCE OF OPERATION This section describes the detailed sequence of operation for the CCU1 control algorithms. Chiller Activation CCU1 control starts only if there is a cooling water demand and the OAT acquired from the network via an auxiliary sensor module (ASM) is above the OAT limits -> Lockout temp. The CCU1 operates in conjunction with up to 60 con- trollers that can require chilled water (FCU series, DXU series, HPU series). The cooling water demand is obtained by the CCU1 from controllers that have been associated with the CCU1 at the LCI user interface during configuration. The CCU1 polls each associated controller to determine if cooling has been requested. Cooling water demand can also be communicated to the CCU1 through a digital input switch or a demand for chiller activation at the LCI. Activation through the digital input switch will not override an OAT limits -> Lockout temp condi- tion. Activation through the LCI will override an OAT limits -> Lockout temp condition. Initial chiller control activates a chiller water pump. The factory installed chiller control, as provided by the chiller manufacturer, detects chiller water loop water flow and activates the chiller. An anti-cycle function provides configurable Chiller settings --> Min On Time and Min Off Time. Chiller Setpoint Adjustment The CCU1 provides setpoint adjustment control of the chiller by integrating to the factory mounted chiller controls with a 0-10 VDC setpoint control signal. The chiller setpoint adjustment provides the ability for the user to change the chilled water supply setpoint through the LCI. The analog output has a user adjustable scaling range. Chiller Pump Control The CCU1 includes support for two chilled water pumps, with only one pump required for normal operation. One of the pumps is designated the lead pump, with the lag pump only being required in the event of a lead pump alarm. Each time the chiller is deactivated, the lead pump designation is transferred to the other pump. When the system is activated, the lead chiller pump is started. If the chiller pump has been commanded on for at least 20 seconds and the chiller flow is off, an alarm is initiated and the lag pump is started. The lag pump also triggers an alarm if it has been commanded on for 20 seconds and flow proof is not established. If both chiller pumps fail, all out- puts are turned off, all control stops, and a dual pump failure alarm is generated. Manual reset of the CCU1 controller from the operator interface or by cycling power to the CCU1 is required to restart control. Condenser Pump Control The CCU1 also includes support for two condenser water pumps, with only one pump required for normal operation. One of the pumps is designated to be the lead pump, with the lag pump only being required in the event of a lead pump failure. Each time the chiller is deactivated, the lead pump designation is transferred to the other pump. When the chilled water pump is started, the lead condenser pump is started also. If the condenser pump has been commanded on for at least 20 seconds and the condenser flow is off, an alarm is initiated and the lag pump is started. The lag pump also triggers an alarm if it has been commanded on for 20 seconds and flow proof is not established. If both condenser pumps fail, all outputs are turned off, all control stops, and a dual pump failure alarm is generated. Manual reset of the CCU1 controller from the operator interface or by cycling power to the CCU1 is required to restart control. Cooling Tower Bypass Valve Control The cooling tower bypass valve is controlled when the CCU1 is configured for a water cooled chiller. The bypass valve position is calculated by a Proportional + Integral (P+I) control loop based on the condenser water return temperature and the condenser water setpoint. The bypass valve control loop is activated 15 seconds after the condenser water flow proof has confirmed flow. As the temperature increases above the All Settings -> Cool Tower Valve SP, the bypass valve is modulated open. The bypass valve is modulated closed as the water temperature decreases below the All Settings -> Cool Tower Valve SP. The cooling tower bypass valve control loop is selectable for direct or reverse acting operation.

17 © 2010 Taco Electronic Solutions, Inc. To prevent the integral component from becoming too large, there is anti-wind up reset protection. This protection clamps the integral value when all of the components add up to more than 100% or less than 0%. The following equa- tions are used for P+I control: KP = Proportional Gain Ki = Integral Gain Error = Inputs --> Cond Rtn Temp - All Settings --> Cool Tower Valve SP I = I + (Ki x Error) Outputs --> Cooling Tower Valve (%) = (KP x (Error + I)) + 50.00% The valve can be set for reverse action by exchanging the maximum and value settings during configuration. That is, if the default maximum of 10 Volts and default minimum of 0 Volts are being used for reverse action, set the minimum to 10 Volts and the maximum to 0 Volts. Cooling Tower Variable Speed Fan Control The cooling tower variable speed fan is controlled when the CCU1 is configured for a water cooled chiller. The cooling tower fan speed is calculated by a P+I control loop based on the condenser water return temperature and the cooling tower water setpoint. The fan speed control loop is activated 15 seconds after the cooling tower bypass valve has mod- ulated to its 100% position (full flow through tower). As the temperature increases above the cooling tower water setpoint, the fan speed is increased. The fan speed is decreased as the water temperature decreases below the Chiller settings --> setpoint. The fan speed control loop is selectable for direct or reverse acting operation. To prevent the integral component from becoming too large, there is anti-wind up reset protection. This protection clamps the integral value when all of the components add up to more than 100% or less than 0%. The following equa- tions are used for P+I control: KP = Proportional Gain Ki = Integral Gain Error = Inputs --> Cond Rtn Temp - All Settings --> Cool Tower Valve SP I = I + (Ki x Error) Outputs --> Cooling Tower Fan (%) = (KP x (Error + I)) + 50.00% Figure 6: Cooling Tower Sequence 0% 100% Condenser Return Water Setpoint Tower Water Bypass Valve Cooling Tower Fan Supply Water Temperature The valve can be set for reverse action by exchanging the maximum and value settings during configuration. Chiller Low Limit Control The CCU1 provides low limit control. When the outside air temperature drops below the low limit setpoint as sensed by the ASM on the network, the CCU1 energizes the chiller low limit output and starts the chilled water pump. The chiller low limit output is interfaced to the factory supplied chiller controls to signal the chiller to not start in response to the chilled water pump operation in the low limit condition. The chilled water pump and chiller low limit output de-energizes when the temperature rises 1 °F above the low limit setpoint.

© 2010 Taco Electronic Solutions, Inc. Chiller Alarm Status The chiller alarm status input is monitored to determine if the chiller is operating properly. The input is used to indicate that an alarm occurred or maintenance is required on the chiller. The unit is not shut down due to a chiller alarm. Runtime Accumulations The total runtime is accumulated for the chiller at HVAC Setup -> Runtimes and Limits -> chiller Runtime, chiller pump 1 at HVAC Setup -> Runtimes and Limits -> chlr Pump 1 Runtime, chiller pump 2 at HVAC Setup -> Runtimes and Lim- its -> chlr Pump 2 Runtime, condenser pump 1 at HVAC Setup -> Runtimes and Limits -> Cond Pump 1 Runtime, con- denser pump 2 at HVAC Setup -> Runtimes and Limits -> Cond Pump 2 Runtime, and fan at HVAC Setup -> Runtimes and Limits -> Fan Runtime. The runtimes can be used to indicate that maintenance is required on the equipment con- trolled by these outputs. An operator or maintenance personnel can reset the runtime once servicing has been per- formed. The runtimes are accumulated in non-volatile memory (NVRAM). Alarms and Events The controller detects certain alarm conditions and sends them to the LCI. Before this can occur, you must use the LCI to configure the controller. Digital Input Alarms The CCU1 monitors the status of the digital inputs and generates alarms for the following events: • Inputs --> Chiller General Alarm Maintenance Alarm A CCU1 provides programmable runtime limits for generating runtime maintenance alarms. When the Runtime Limits - > chiller, Runtime Limits ->pump or Runtime Limits -> fan exceeds these limits, a maintenance alarm is sent to the LCI. Water Temperature Alarms After a 1 minute delay following chiller startup, the CCU1 generates high and low limit alarms for the monitored water temperatures. A programmable water temperature alarm limit offset is provided. The temperature limits are calculated based on the alarm limit setpoints and the alarm limit offset. Chiller Temp High Limit = Chiller Settings -> Max Water Temp + Water Temp Alarm Hys Chiller Temp Low Limit = Chiller Settings -> Min Water Temp - Water Temp Alarm Hys When the measured water temperature exceeds the high limit, a high limit alarm is generated. When the water temper- ature drops below the low limit, a low limit alarm is generated. A return to normal is generated when the water temper- ature is between the high and low limit. Pump Alarms If the chiller pump has been commanded on for at least 20 seconds and the chiller flow proof is off, an alarm is initiated and the lag pump is started. The lag pump also triggers an alarm if it has been commanded on for 20 seconds and flow proof is not established. If both chiller pumps fail, all outputs are turned off, all control stops, and a dual pump failure alarm is generated. Manual reset of the CCU1 controller from the operator interface or by cycling power to the CCU1 is required to restart control. If the condenser pump has been commanded on for at least 20 seconds and the condenser flow proof is off, an alarm is initiated and the lag pump is started. The lag pump also triggers an alarm if it has been commanded on for 20 sec- onds and flow proof is not established. If both condenser pumps fail, all outputs are turned off, all control stops, and a dual pump failure alarm is generated. Manual reset of the CCU1 controller from the operator interface or by cycling power to the CCU1 is required to restart control.

19 © 2010 Taco Electronic Solutions, Inc. Automatic Configuration The CCU1 and iWorX Local Control Interface (LCI) use a self-configuring network management scheme requiring no external tools, binding, or LONWORKS knowledge. The LCI recognizes and configures the CCU1 when the controller’s service pin is pressed. The controller’s status light flashes green until the controller is configured, and will be solid green after the controller is configured. Once the service pin has been pressed, no further action is required by the user; the controller is fully accessible to the LCI. Users may bind to SNVTs on the CCU1 with LNS or other LONWORKS tools if they wish. The LCI also provides network supervision of the CCU1. The LCI periodically sends a "ping" message to the CCU1, which elicits a response. If the response fails, an alarm is displayed on the LCI. The LCI also uses the "ping" message to refresh the occupancy mode and other system wide data. Networking Controllers Associations can only be done in a network with an LCI2 present. Please refer to the iWorX LCI2 Application Manual for detailed instructions. CCU1 can be associated and communicate with other controllers. CCU1 can receive the cooling demands form asso- ciated control. Following is a list of the controllers that can be associated with the CCU1. • DXU series • HPU series • FCU series To associate a CCU1 to controllers, start from the LCI main screen; press Controllers and then select the CCU1. From within the CCU1, select HVAC Setup and then press the Members button. Once the members screen appears, a list of controllers that the CCU1 can be grouped to will be shown. Press the name of the controller to associate. The selected controller will turn “RED” color and “Associated” status will be displayed on the right side. To change the member status of a controller, just press that controller. It will toggle “Member” or “Non-Member” with each press. If a controller has been selected or deselected, you must press Save afterward to confirm the new setting.

© 2010 Taco Electronic Solutions, Inc. CONTROLLER IDENTIFICATION Once the CCU1 is properly installed and recognized by the Local Control Interface (LCI), the LCI can be used to con- figure the settings of the controller. This section describes the commands available on the LCI for configuration of the CCU1, and the meanings and default values for controller parameters. For more information on using the LCI, see the iWorX LCI Application Guide. Inputs The Inputs screen displays the current values of the CCU1’s inputs. These values cannot be changed. Outputs This screen displays the current values of the CCU1’s outputs. These values cannot be changed. Input Range Description Outside Temp -30.00 to 230.00 °F (-34.4 to 110.00 °C) Outside air temperature reported by an external temperature sensor over the network. Chiller Flow Off, On Status of the CFP switch. Condenser Flow Off, On Status of the CDFP switch. Chlr General Alarm Off, On Status of the chiller’s alarm output. Cooling Water Demand Off, On Status of the CWD switch. Chiller Supply Temp -30.00 to 230.00 °F (-34.40 to 110.00 °C) Temp. reported by CWS sensor. Chiller Return Temp -30.00 to 230.00 °F (-34.40 to 110.00 °C) Temp. reported by CWR sensor. Condenser Supply Temp. -30.00 to 230.00 °F (-34.40 to 110.00 °C) Temp. reported by CDS sensor. Condenser Return Temp. -30.00 to 230.00 °F (-34.40 to 110.00 °C) Temp. reported by CDR sensor. Occupancy Mode Unocc, Occ Indicates the current occupancy mode. Output Range Description Unit Status Mode Off, Cooling Current mode of the chiller system. Cooling Tower Valve 0.00% to 100.00% Status of the cooling tower valve output. Cooling Tower Fan 0.00% to 100.00% Status of the cooling tower fan output. In Alarm? On, Off Current alarm status of the chiller. Output Status Chiller Pump 1 Off, On Status of chiller pump 1. Chiller Pump 2 Off, On Status of chiller pump 2. Condenser Pump 1 Off, On Status of condenser pump 1. Condenser Pump 2 Off, On Status of condenser pump 2. Chiller Low Limit Off, On Status of the chiller low limit output.

21 © 2010 Taco Electronic Solutions, Inc. All Settings This screen displays all settings used by the CCU1 controller and provides access to edit all the parameters from a sin- gle screen. Cool Tower Valve Enables the user to view and set parameters directly related to control of the cooling tower valve. Cool Tower Fan Enables the user to view and set parameters directly related to control of the cooling tower fan. Setting Range Default Description Chiller Enable Auto, On Auto Auto: Chiller will follow the cooling demand set by other controllers. On: Chiller enabled regardless of cooling demand. Cool Tower Valve SP 32 to 80.6 °F (0 to 27 °C) 45.0 °F (7.2 °C) Valve Set Point Cool Tower Valve NA Structure Valve Settings Cool Tower Fan SP 32 to 80.6 °F (0 to 27 °C) 50.0 °F (10.0 °C) Fan Set Point Cool Tower Fan NA Structure Fan settings Runtime Limits NA Structure Runtime settings OAT Limits NA Structure OAT temp limit settings Chiller Settings NA Structure Chiller settings Chlr Alm Temp Limits NA Structure Chiller settings Cond Alm Temp Limits NA Structure Condenser settings Water Temp Alarm Hys 0 to 10.0 °F (0 to 5.6 °C) 5.0 °F (2.8 °C) Water temp alarm hysteresis Zone Limit 0 to 60 1 Number of zones requiring cooling before the chiller will be enabled Setting Range Default Description Kp 0.00 to 100.00% per degree of temperature 50.00% Proportional gain for P+I control of the cooling tower valve. Ki 0.00 to 100.00% 0.05% Integral gain for P+I control of the cooling tower valve. Min AO Voltage 0.0 to 10.0 Volts 0.0 Volts Minimum voltage of the cooling tower valve output. Max AO voltage 0.0 to 10.0 Volts 10.0 Volts Maximum voltage of the cooling tower valve output. Setting Range Default Description Kp 0.00 to 100.00% per degree of temperature 50.00% Proportional gain for P+I control of the cooling tower fan. Ki 0.00 to 100.00% 0.05% Integral gain for P+I control of the cooling tower fan. Min AO voltage 0.0 to 10.0 Volts 0.0 Volts Minimum voltage of the cooling tower fan output. Max AO voltage 0.0 to 10.0 Volts 10.0 Volts Maximum voltage of the cooling tower fan output.

© 2010 Taco Electronic Solutions, Inc. Runtime Limits Enables the user to view and set parameters directly related to the runtime limits for maintenance alarms. OAT Limits (Outside Temperature) Enables the user to view and set parameters directly related to the outside temperature limits. Chiller Settings Enables the user to view and set parameters directly related to the chiller settings. Chiller Alm Temp Limits (Chiller Temperature Limits for Alarm) Enables the user to view and set parameters directly related to the chiller temperature alarm limits. Setting Range Default Description Chiller 0 to 65535 hours 1000 hours Chiller runtime after which a main- tenance alarm is generated. Fan 0 to 65535 hours 1000 hours Cooling tower fan runtime after which a maintenance alarm is gen- erated. Pump 0 to 65535 hours 1000 hours Total pump runtime after which a maintenance alarm is generated. Setting Range Default Description Low Limit 32.00 to 140.00 °F (0.00 to 60.00 °C) 32.0 °F (0.0 °C) Outdoor air temperature below which low limit control is enabled. Cutoff Temp 32.00 to 140.00 °F (0.00 to 60.00 °C) 52.0 °F (11.1 °C) Outdoor air temperature below which the chiller is disabled. Setting Range Default Description Setpoint 32.00 to 80.60 °F (0 to 27.00 °C) 44.9 °F (7.2 °C) Desired temperature of the chiller supply. Type Water, Air Water Type of chiller being controlled, water-cooled or air-cooled. Min Supply Temp 32.00 to 80.60 °F (0.00 to 27.00 °C) 40 °F (4.4 °C) Minimum chiller water temp Max Supply Temp 32.00 to 80.60 °F (0.00 to 27.00 °C) 60 °F (15.6 °C) Maximum chiller water temp Min On Time 0 to 180 minutes 30 minutes Minimum amount of time the chiller must remain on. Min Off Time 0 to 180 minutes 30 minutes Minimum amount of time the chiller must remain off. Setting Range Default Description Min Supply Temp 32.00 to 140.00 °F (0.00 to 60.00 °C) 43.0 °F (6.1 °C) Chiller supply temperature below which an alarm is generated. Max Supply Temp 32.00 to 140.00 °F (0.00 to 60.00 °C) 60.0 °F (15.56 °C) Chiller supply temperature above which an alarm is generated. Min Return Temp 32.00 to 140.00 °F (0.00 to 60.00 °C) 43.0 °F (6.1 °C) Chiller return temperature below which an alarm is generated. Max Return Temp 32.00 to 140.00 °F (0.00 to 60.00 °C) 60.0 °F (15.56 °C) Chiller return temperature above which an alarm is generated.

23 © 2010 Taco Electronic Solutions, Inc. Cond Alm Temp Limits (Condenser Temperature Limits for Alarm) Enables the user to view and set parameters directly related to the condenser temperature alarm limits. Alarms The table below describes the alarms you may encounter and how they are reset. Setting Range Default Description Min Supply Temp 32.00 to 140.00 °F (0.00 to 60.00 °C) 43.0 °F (6.1 °C) Condenser supply temperature below which an alarm is generated. Max Supply Temp 32.00 to 140.00 °F (0.00 to 60.00 °C) 60.0 °F (15.56 °C) Condenser supply temperature above which an alarm is generated. Min Return Temp 32.00 to 140.00 °F (0.00 to 60.00 °C) 43.0 °F (6.1 °C) Condenser return temperature below which an alarm is generated. Max Return Temp 32.00 to 140.00 °F (0.00 to 60.00 °C) 60.0 °F (15.56 °C) Condenser return temperature above which an alarm is generated. Alarm Range Alarm Trigger Alarm Reset Chil Sup High Temp Alarm Normal, Alarm If chiller water supply temperature is greater than Chiller Supply Temperature Max plus water temperature limits. Automatic when chiller supply temper- ature returns to normal range. Chil Sup Low Temp Alarm Normal, Alarm If chiller water supply temperature is less than Chiller Supply Temperature Min minus water temperature limits. Automatic when chiller supply temper- ature returns to normal range. Chil Ret High Temp Alarm Normal, Alarm If chiller water return temperature is greater than Chiller Return Temperature Max plus water temperature limits. Automatic when chiller return temper- ature returns to normal range. Chil Ret Low Temp Alarm Normal, Alarm If Chiller water return temperature is less than Chiller Return Temperature Min minus water temperature limits. Automatic when chiller return temper- ature returns to normal range. Cond Sup High Temp Alarm Normal, Alarm If Condenser water supply temperature is greater than Condenser Supply Tem- perature Max plus water temperature limits. Automatic when condenser supply temperature returns to normal range. Cond Sup Low Temp Alarm Normal, Alarm If Condenser water supply temperature is less than Condenser Supply Tempera- ture Min minus water temperature limits. Automatic when condenser supply temperature returns to normal range. Cond Ret High Temp Alarm Normal, Alarm If Condenser water supply temperature is less than Condenser Return Tempera- ture Max plus water temperature limits. Automatic when condenser return temperature returns to normal range. Cond Ret Low Temp Alarm Normal, Alarm If Condenser water supply temperature is less than Condenser Return Tempera- ture Min minus water temperature limits. Automatic when condenser return temperature returns to normal range. Chiller Pump 1 Failed Normal, Alarm If chiller pump 1 fails. Automatic unless there is a Dual Pump Failure; See Dual Pump Fail- ure. Chiller Pump 2 Failed Normal, Alarm If chiller pump 2fails. Automatic unless there is a Dual Pump Failure; See Dual Pump Fail- ure. Condenser Pump 1 Failed Normal, Alarm If condenser pump 1 fails. Automatic unless there is a Dual Pump Failure; See Dual Pump Fail- ure.

© 2010 Taco Electronic Solutions, Inc. Condenser Pump 2 Failed Normal, Alarm If condenser pump 2 fails. Automatic unless there is a Dual Pump Failure; See Dual Pump Fail- ure. Dual Pump Failure Normal, Alarm If both pumps fail. Reset the controller (power cycle). Chiller Alarm Normal, Alarm This is a physical input received from the chiller. Automatic when chiller returns to nor- mal range. Alarm Range Alarm Trigger Alarm Reset

25 © 2010 Taco Electronic Solutions, Inc. TROUBLESHOOTING Diagnostic LEDs The controller has 3 LED indicators. These indicators can aid in troubleshooting equipment operation problems. The following table lists the functions of the controller’s LEDs in the order they appear from left to right on the unit. Figure 7: CCU1 Controller LEDs Status Network Service LED Indication Status – Solid green when running and configured by an LCI (networking) – Flashing green when running and NOT configured by an LCI (stand-alone) – Solid red when a fault condition exists (control shut down) – Blinking Red - the controller has a device failure – Solid Amber - The controller has not received a LCI ping message in over 10 minutes and is part of a network. Network – Yellow while the controller is transmitting data onto the FTT-10A network – Green when there is network activity – Off when there is no network activity Service – Illuminated when the service pin is depressed or when a controller gets configured by the LCI.

© 2010 Taco Electronic Solutions, Inc. Troubleshooting Tips The following table provides tips on resolving common issues. Getting Help Components within an iWorX CCU1 controller cannot be field repaired. If there is a problem with a controller, follow the steps below before contacting your local TES representative or TES technical service. 1.Make sure controllers are connected and communicating to desired devices. 2.Record precise hardware setup indicating the following: Version numbers of applications software. Controller firmware version number. A complete description of difficulties encountered. Problem Solution Controller is not running and Status LED is not illuminated. No power to controller. Verify the voltage on the controller’s power connector (24 VAC). How do I reset the controller? The controller can be reset by the LCI, or you can cycle power to the controller. Refer to the LCI documentation for more information on resetting the controller using the LCI. Can my iWorX system contain multi- ple CCU1 controllers? No, the system can only recognize one. Thermistor readings fluctuate rapidly, sometimes by several degrees. The controller may not be properly grounded. The controller’s ground (GND) pin (T40) must be connected to earth ground. Also ensure that the controller’s digital inputs are dry contacts and that no voltage is being applied or switched to the inputs. How do I associate my other control- lers with the CCU1? Use the CCU1’s grouping mechanism, specifically HVAC Setup --> Members on the CCU1 screen of the LCI. What iWorX controllers can be part of a CCU1’s group? Only FCU series, DXU series and HPU series controllers can be part of the CCU1's group and demand cooling from it. Several controllers are requesting cooling, but the chiller and pumps have not been enabled. The Zone Limit setting may be set higher than the number of zones that are currently requesting cooling. The chiller and pumps will not be enabled until the number of zones requesting cooling is greater than the Zone Limit setting. If the number of controllers requesting cooling exceeds the Zone Limit setting, but the chiller is still not enabled, the outside air temperature may be less than the Outdoor Air Temp. Lockout setting. I only have one chiller pump; how can I disable lead/lag operation? The lead/lag function is built into the controller and cannot be disabled. However, you can wire both chiller pump outputs in parallel from the controller to the existing pump and the system will operate normally. The same can be done for the condenser pump outputs if you have only one condenser pump. The LCI is reporting a dual pump fail- ure. How do I know which pumps have failed? Check the pump alarms that precede the dual pump failure alarm. These two alarms will indicate which two pumps have failed, the chiller pumps or the condenser pumps.

iWorX and iView are trademarks of Taco, Inc. © 2010 Taco Electronic Solutions, Inc. LON, LONWORKS, & LONMARK are trademarks of Echelon Corporation CONTROLS MADE EASY® Taco Electronic Solutions, Inc., 1160 Cranston Street, Cranston, RI 02920 Telephone: (401) 942-8000 FAX: (401) 942-2360. Taco (Canada), Ltd., 8450 Lawson Road, Unit #3, Milton, Ontario L9T 0J8. Telephone: 905/564-9422. FAX: 905/564-9436. Taco Electronic Solutions, Inc. is a subsidiary of Taco, Inc. Visit our web site at: http://www.taco-hvac.com Taco Electronic Solutions, Inc. (TES) will repair or replace without charge (at the company's option) any product or part which is proven defective under normal use within one (1) year from the date of start-up or one (1) year and six (6) months from date of shipment (whichever occurs first). In order to obtain service under this warranty, it is the responsibility of the purchaser to promptly notify the local TES stocking distribu- tor or TES in writing and promptly deliver the subject product or part, delivery prepaid, to the stocking distributor. For assistance on war- ranty returns, the purchaser may either contact the local TES stocking distributor or TES. If the subject product or part contains no defect as covered in this warranty, the purchaser will be billed for parts and labor charges in effect at time of factory examination and repair. Any TES product or part not installed or oper- ated in conformity with TES instructions or which has been subject to accident, disaster, neglect, misuse, misapplication, inadequate operating environment, repair, attempted repair, modification or alteration, or other abuse, will not be covered by this warranty. TES products are not intended for use to sup- port fire suppression systems, life support sys- tems, critical care applications, commercial aviation, nuclear facilities or any other applica- tions where product failure could lead to injury to person, loss of life, or catastrophic property damage and should not be sold for such pur- poses. If in doubt as to whether a particular product is suitable for use with a TES product or part, or for any application restrictions, consult the applicable TES instruction sheets or in the U.S. contact TES at 401-942-8000 and in Canada contact Taco (Canada) Limited at 905-564- 9422. TES reserves the right to provide replacement products and parts which are substantially simi- lar in design and functionally equivalent to the defective product or part. TES reserves the right to make changes in details of design, con- struction, or arrangement of materials of its products without notification. TES OFFERS THIS WARRANTY IN LIEU OF ALL OTHER EXPRESS WARRANTIES. ANY WARRANTY IMPLIED BY LAW INCLUDING WARRANTIES OF MERCHANTABILITY OR FITNESS IS IN EFFECT ONLY FOR THE DURATION OF THE EXPRESS WARRANTY SET FORTH IN THE FIRST PARAGRAPH ABOVE. THE ABOVE WARRANTIES ARE IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR STATUTORY, OR ANY OTHER WARRANTY OBLIGATION ON THE PART OF TES. TES WILL NOT BE LIABLE FOR ANY SPE- CIAL, INCIDENTAL, INDIRECT OR CONSE- QUENTIAL DAMAGES RESULTING FROM THE USE OF ITS PRODUCTS OR ANY INCI- DENTAL COSTS OF REMOVING OR REPLACING DEFECTIVE PRODUCTS. This warranty gives the purchaser specific rights, and the purchaser may have other rights which vary from state to state. Some states do not allow limitations on how long an implied warranty lasts or on the exclusion of incidental or consequential damages, so these limitations or exclusions may not apply to you. LIMITED WARRANTY STATEMENT Notes: