DriSteem DS 301 Manuals

1 Safety, Installation, and Operation Manual DRISTEEM Duct Mounted On-Off Humidistat (DS 301) and Duct Mounted Modulating Humidistat (DS 401) READ COMPLETE INSTALLATION INSTRUCTIONS BEFORE STARTING. WARNING 1. Contact with energized electrical circuits may cause serious injury from electrical shock. Disconnect electrical power to the Humidifier before starting installation. 2. Sharp edges may cause serious injury from cuts. Use care when cutting plenum openings and handling ductwork. WARNING This product must be installed by a qualified heating and air conditioning contractor. Failure to do so could result in serious injury from electrical shock or damage to product and voids product warranty due to possible product misapplication. CAUTION 1. Do not set humidity higher than recommended or moisture can accumulate, which may cause bacteria and mold growth or dripping water into building spaces. Dripping water may cause property damage; bacteria and mold growth may cause illness. 2. Do not set humidity up to recommended levels if there is condensation on the inside of windows. Condensation damage may result. 3. Do not mount Humidistat on supply plenum or duct. High supply temperatures will cause the control to malfunction. 4. When installing Humidistat on downflow furnaces, ensure that blower continues to run as programmed after a heat call is satisfied to eliminate high temperatures from damaging the Humidistat. THESE INSTALLATION INSTRUCTIONS ARE FOR THE HUMIDISTAT ONLY! For DRISTEEM® Humidifier installation, follow DRISTEEM Humidifier Installation Instructions. PRINCIPLES OF OPERATION The DRISTEEM Duct Mounted On-Off Humidistat (DS 301) and Duct Mounted Modulating Humidistat (DS 401) are designed to be installed in the return duct or return plenum only of the HVAC system. The Control supplies a modulating signal to the humidifier. In terms of outdoor temperature compensation, the Control can be set up in automatic or manual mode, regardless of the humidifier model being controlled. The automatic mode incorporates the supplied Outdoor Temperature Sensor to automatically adjust the control set-point based on the outdoor temperature. The manual mode does not require an outdoor temperature measurement and is used for specific set-point control with the control set- point manually adjusted by the user. The DRISTEEM Duct Mounted On-Off Humidistat (DS 301) and Duct Mounted Modulating Humidistat (DS 401) will accurately control the humidity in the conditioned space within the range of 15% – 55% RH. CONTROL TYPE ON-OFF CONTROL The DRISTEEM Duct Mounted On-Off Humidistat (DS 301) sends a 10 VDC signal to the humidifier when the measured return air relative humidity is 3% or more below the set-point. This energizes the humidifier at 100% output. The Humidifier is either on at 100% capacity or it is off. MODULATING CONTROL The DRISTEEM Duct Mounted Modulating Humidistat (DS 401) sends a signal to the humidifier between 0 and 10 VDC based on: a) the difference between measured relative humidity and set-point relative humidity, and b) where this difference or ‘error’ falls within an adjustable proportional control band. The output of the Control, and therefore the Humidifier, is a ‘proportion’ of maximum output based on ‘a’ and ‘b’ above. See Figure 1 for graphical representation of the output.