Automatic Digital Humidifier Control Safety and Installation Instructions R E A D C O M P L E T E I N S TA L L AT I O N I N S T R U C T I O N S A N D T E M P L AT E B E F O R E S TA R T I N G . WARNING ATTENTION INSTALLER: 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.
WARNING 1. 120 volts may cause serious injury from electrical shock. Disconnect electrical power to the HVAC system before starting installation. 2. Sharp edges may cause serious injury from cuts. Use care when cutting plenum openings and handling ductwork. CAUTION 1. Do not set humidity higher than recommended. Condensation damage may result. 2. Do not set humidity up to recommended levels if there is condensation on the inside of windows of any unheated living space. Condensation damage may result. 3.
STEP 2: Disassemble the Humidifier Control Figure B Remove the knob. Remove the cover by pulling at the bottom and swinging it out and upward. STEP 3: Check the Mode Switch Use the “OFF” setting to turn the Water Panel Change Indicator OFF. NOTE: When using the Model 50 Current Sensing Relay, the Water Panel Change Indicator MUST be OFF. See Figure G (on page 11) for the mode switch (labeled A and B). Make sure the switch is correctly set for the type of humidifier installed.
DUCT (SHEET METAL) MOUNT: STEP 5: Determine Location for Humidifier Control and Mount Control Humidifier Control must be mounted on the Return Duct, at least 6 inches upstream of the following (see Figure C): After location for Control is selected, drill a 3/4 inch hole for the RH sensor (the RH sensor extends from the back of the Humidifier Control).
STEP 6: Determine Location for Outdoor Temperature Sensor Figure D – Fiber Board Duct Mount The location of the Outdoor Temperature Sensor must meet these three requirements: CONTROL BOARD 1. Must be mounted on North, East or West side of house out of direct sunlight COVER GASKET 2. Must be at least 3 feet from all exhaust vents SCREW (x2) 3. Must be above expected snow line (see Figure E) KNOB Incorrect humidity levels will result if these requirements are not met.
STEP 9: Route the Wire from Control to Sensor STEP 8: Alternate Location for Outdoor Temperature Sensor Run wire to the outdoor temperature sensor. Sensor is not affected by lead length. Do not run outdoor temperature sensor alongside wires carrying high voltage (120 VAC or higher). Secure the sensor bracket with a #8 screw. The Sensor can also be mounted in the center of either: • PVC fresh air intake pipe for the HVAC system OR • fresh air intake duct. Mount the sensor with a #8 galvanized screw.
STEP 11: Power Source for Humidifier Control – Terminals R and C Installing the Humidifier Control for Manual Operation If it is not feasible to install the Outdoor Temperature Sensor, the Humidifier Control can be operated in Manual Mode. 1. Connect the Manual Mode Resistor Case wires to the terminals labeled “ODT” on the Humidifier Control. 2. Position the Manual Mode Resistor Case so that the Resistor Case extends from the bottom edge of the base. 3.
USING FURNACE ACCESSORY TERMINALS TO DETECT FURNACE OPERATION (FIGURE J) USING FURNACE TERMINALS TO DETECT FURNACE BLOWER OPERATION (FIGURE K) See the furnace manual for voltage and operation of the accessory terminals. If accessory terminals are 120 Volts, install a 24 VAC transformer. This configuration allows the humidifier to run only during heat call, even if the thermostat is set for continuous fan operation.
OPERATING THE HUMIDIFIER WITH CONTINUOUS FAN OPERATION (FIGURE L) This configuration allows the humidifier to run whenever the HVAC blower is running and the Humidifier Control is calling for humidity. This option is for applications that require more humidity than can be delivered during heat calls. HEAT PUMP WIRING (FIGURE M) This configuration allows the humidifier to run whenever the heat pump blower is running (and the Humidifier Control is calling for humidity).
USING MODEL 50 CURRENT SENSING RELAY TO DETECT FURNACE BLOWER OPERATION (FIGURE N) This option is to be used only if the furnace terminals or accessory terminals are not used. NOTE: The Water Panel Change Indicator must be set to the “OFF” position for this option. MODEL 8570 THERMOSTAT OPTION (FIGURE P) The Model 8570 Thermostat provides the signal that the HVAC is operating. The outdoor temperature sensor can be connected to the Humidifier Control or to the Model 8570.
SYSTEM CHECKOUT 1. Replace the cover by snapping it into the Humidifier Control base. Also replace the knob onto the Control. 7. Setting the Humidifier Control: 2. Restore power to the heating system. • If the home is occupied, set the Humidifier Control to “Normal” (For Manual Mode, set to 35%) 3. Activate the HVAC system or heat pump. • If the home is vacant, set the Humidifier Control to “OFF” 4.
TROUBLESHOOTING TROUBLESHOOTING PROCEDURE (CONTINUED) Applies to both Automatic and Manual Operation unless indicated otherwise. SYMPTOM Call Dealer For Service Light Flashing (see Figure Q) TROUBLESHOOTING PROCEDURE Display Error Code: E1: RH Sensor Rotate Humidifier Control knob to the “Test/Reset” position. After 5 seconds, the green “Humidifier On” light will blink, resetting the error. If E1 returns, replace the Humidifier Control.
SYMPTOM Humidifier does not operate in “Test/Reset” mode TROUBLESHOOTING PROCEDURE • Make sure that the blower is operating and the HVAC system is calling for heat. • Check wiring diagrams for correct Humidifier Control installation. • If connected to either a Model 400 or 400A humidifier, make sure both floats in the bottom of the scale control insert are in the down position. If necessary, dump out water to lower the floats.
SYMPTOM SYMPTOM Humidifier operates only in “Test/Reset” mode Humidifier operates constantly • If outdoor temperature is greater than 60°F or less than -30°F, the Humidifier Control will only operate in the “Test/Reset” mode (for 1 minute).
SYMPTOM Humidifier or Humidifier Control “chatters” or clicks On and Off rapidly TROUBLESHOOTING PROCEDURE • Check for steady 22 VAC to 30VAC across the “R” and “C” terminals of the Humidifier Control with a voltmeter. • Check, with a voltmeter, that the HVAC signal across the “W/G” and “Cf” terminals of the Humidifier Control is a steady 22 VAC to 30 VAC. • Make sure that the Outdoor Temperature Sensor wiring is not running alongside other wires carrying high voltage (120 VAC or higher).
