TROUBLESHOOTING PROCEDURE
• Make sure furnace blower is operating and thermostat is calling for heat.
• Make sure the Outdoor Temperature Sensor is connected to the “ODT” terminals of the control. (For Manual Operation,
make sure Manual Mode Resistor Case is in place.)
• Check wiring diagram for correct
Humidifier Control installation.
• Check voltage at Humidifier Control “R”
and “C” terminals. Voltage should be
22 VAC minimum – 30 VAC maximum.
• Check Current Sensing Relay (if used)
for correct installation (see Current
Sensing Relay Installer’s Guide. The
Guide ships with the relay or may be
obtained from your local distributor).
Do not use Current Sensing Relay in
transformer circuit or “R” and “C”
circuit of Humidifier Control. Current
Sensing Relay is to be used in the “H”
circuit only.
• In “Test” mode, humidifier will
operate for 1 minute only. DO NOT
LEAVE IN TEST MODE AS
HUMIDIFIER WILL NOT OPERATE
• Make sure saddle valve is open.
Humidifier Control Troubleshooting Guide
Applies to both Automatic and Manual Operation unless indicated otherwise.
SYMPTOM
Humidifier does
not operate in
“Test” mode
System Checkout
1. For system Test/Reset, be sure that 24 VAC is applied to the “R” and “C” terminals
of Humidifier Control.
2. Snap the door back onto the Humidifier Control Base.
3. Activate furnace blower and be sure thermostat is calling for heat.
4. Rotate the control knob of Humidifier Control clockwise to the “Test/Reset” position.
When the knob is set in the “Test/Reset” position, the green “Change Humidifier Pad”
light will blink. Make sure the knob is not left in the “Test/Reset” position when the
installation is done. Rotating knob to test position resets the humidifier pad change timer
to zero. The Control must be energized to reset the Humidifier Pad Indicator.
5. If all is set up properly, you should be able to hear the solenoid valve click open.
In “Test/Reset” mode, the Humidifier will operate for 1 minute.
6. If the humidifier does not activate with the
Humidifier Control in the “Test/Reset” position,
refer to troubleshooting guide.
7. Setting the Humidifier Control:
• If home is occupied, set Humidifier Control to
“Normal” (For Manual Operation, set to 35%)
• If home is vacant, set Humidifier Control to “Off”
8. Inform homeowner to refer to the Owner’s Manual
for the initial adjustment period.
9. Make sure the Red Diagnostic Light is not lit. If the
Red Diagnostic Light is lit, re-check your wiring.
HUMIDIFIER CONTROL TEMPLATE
Sharp edges on the opening may cause cuts. Use care when cutting the plenum opening and installing
the Humidifier Control.
• Do not mount Humidifier Control on supply plenum or duct. The Control will not withstand supply
temperatures and will malfunction!
• When installing Humidifier Control on counterflow furnaces, ensure blower continues to run after a
heat call is satisfied to eliminate high temperatures from damaging the Humidifier Control.
• Do not mount Humidifier Control downstream of the bypass outlet. The Control will not operate correctly
due to false humidity readings.
1. CUT OUT TEMPLATE ALONG EDGES.
2. PLACE TEMPLATE ON THE RETURN PLENUM UPSTREAM OF (BEFORE) THE HUMIDIFIER CONNECTION.
3. TRACE OUTSIDE EDGES OF TEMPLATE.
4. REMOVE TEMPLATE AND ACCURATELY CUT PLENUM OPENING.
5. USING 4 SHEET METAL SCREWS, INSTALL HUMIDIFIER CONTROL IN PLENUM OPENING.
AUTOMATIC CONTROL
WIRING TERMINALS
PO
WER
BYP
ASS
SWITCH POSITION
R
C
H
ODT
24V
24 VAC
OUTDOOR
TEMPERATURE
SENSOR
FAN POWERED
HUMIDIFIER
FURNACE
LOW VOLTAGE
TERMINALS
(2 VA MINIMUM)
B / C
W1
HUMIDIFIER CORD
PLUGGED INTO
120 VAC POWER SOURCE
AUTOMATIC CONTROL
WIRING TERMINALS
R
C
H
ODT
24V
OUTDOOR
TEMPERATURE
SENSOR
FAN POWERED
HUMIDIFIER
HUMIDIFIER CORD
PLUGGED INTO
120 VAC POWER SOURCE
24 VAC
120 VAC
TRANSFORMER
(NOT SUPPLIED)
120 VAC
“HUM” OR “EAC”
TERMINALS
ON FURNACE
PO
WER
BYP
ASS
SWITCH POSITION
AUTOMATIC CONTROL
WIRING TERMINALS
R C
H ODT
24V
24 VAC
120 VAC
TRANSFORMER
(FURNISHED)
FURNACE
ACCESSORY
TERMINALS
“HUM” “HUM”
H N
120 VAC
“HUM” OR “EAC”
TERMINALS
ON FURNACE
24 VAC
120 VAC
TRANSFORMER
(FURNISHED)
AUTOMATIC CONTROL
WIRING TERMINALS
R C
H ODT
24V
BYPASS
HUMIDIFIER
BYPASS
HUMIDIFIER
OUTDOOR
TEMPERATURE
SENSOR
OUTDOOR
TEMPERATURE
SENSOR
Diagram A
FOR HUMIDIFIER
OPERATION DURING
“HEAT CALL” ONLY
Diagram B
FOR HUMIDIFIER
OPERATION WHEN
BLOWER IS ENERGIZED
Diagram C
FOR HUMIDIFIER
OPERATION DURING
“HEAT CALL” ONLY
Diagram D
FOR HUMIDIFIER
OPERATION WHEN
BLOWER IS ENERGIZED
FAN POWERED HUMIDIFIER WIRING DIAGRAM
BYPASS HUMIDIFIER WIRING DIAGRAM
90-1048
90-1125
CAUTION
WARNING
