Humidifier Control Troubleshooting Guide
Applies to both Automatic and Manual Operation unless indicated otherwise.
Humidifier operates
constantly
Humidifier or Humidifier
Control “chatters” or
clicks ON and OFF rapidly
Red Diagnostic Light is on
(See
Figure H
)
• If the humidity level in the home is less than the knob setting, the Humidifier Control will operate the Humidifier until
the humidity level is higher than the knob setting.
• In the “Test” mode, verify unit will operate for approximately one minute.
• Check the resistance of the Outdoor Temperature Sensor as instructed above.
• Make sure the Outdoor Temperature Sensor is mounted completely outside the house on the North, East, or West
side of the house and out of direct sunlight. (Automatic Mode Only).
• Rotate the Humidifier Control knob counterclockwise to the “Off” position, and observe whether the humidifier turns
off. If the humidifier still operates in the “Off” position, perform the following:
1. Check wiring diagram for correct Humidifier Control Installation.
2. Remove wires from Humidifier Control’s “H” terminals. If Humidifier continues to operate, replace solenoid valve.
• Check for steady 22 VAC – 30 VAC with voltmeter.
• Make sure Outdoor Temperature Sensor wiring is not run alongside wires carrying high voltage (120 VAC or higher).
(Automatic Only)
• Check that the wiring is correct.
• Measure the resistance of the Outdoor Temperature Sensor by
removing the leads from the terminal and measuring the resistance
across the wires with an ohmmeter. Confirm the reading with the
temperature in
Table 1
. (For Manual Operation, verify that the
resistance across the leads of the Manual Mode Resistor Case is
between 44,000 and 48,000 ohms).
10006971
B2204076B
18-CH31D1-3 6/08
24V
R
C
BYP
ASS
ODT
H
PO
WER
RED
DIAGNOSTIC
LIGHT
Figure H
Humidifier operates only
in “Test” mode
TABLE 1
Resistance
k
Ω
-30˚F
-20˚F
-10˚F
0˚F
10˚F
20˚F
30˚F
40˚F
50˚F
60˚F
70˚F
80˚F
90˚F
100˚F
230.6
163.8
117.6
85.4
62.6
46.3
34.6
26.1
19.9
15.3
11.9
9.4
7.4
5.9
Outdoor
Temperature
• If outdoor temperature is greater than 60°F or less than -30°F, the Humidifier Control will
only operate in the “Test” mode. (For One Minute)
• If the humidity level in the home is higher than the knob setting, the Humidifier Control
will not operate the Humidifier.
• Check the resistance of the sensor by removing the leads of the Outdoor Temperature
Sensor from the terminals and measuring the resistance across the wires with an
ohmmeter. Compare reading to outdoor temperature in
Table 1
. (For Manual Operation,
verify that resistance across the leads of Manual Mode Resistor Case is between 44,000
and 48,000 ohms).
• Make sure the Outdoor Temperature Sensor is mounted completely outside the house
on the North, East, or West side of the house and out of direct sunlight. (Automatic
Mode Only)
• If Outdoor Temperature Sensor is mounted in fresh air intake duct, make sure the probe
is no more than 36 inches from the outside wall. (Automatic Mode Only)
• Make sure the Outdoor Temperature Sensor is located at least 3 feet away from all
exhaust vents. (Automatic Mode Only)
SYMPTOM
TROUBLESHOOTING PROCEDURE
HUMIDIFIER
CONTROL
TEMPLATE
• Call your installer to have your Humidifier Pad changed, or visit your installer to purchase a new Humidifier Pad.
Follow the instructions on the Humidifier Pad box.
“Change Humidifier Pad”
Indicator is lit.
90-1016
TOP
USE AS HUMIDIFIER CONTROL TEMPLATE
4-11/16”
2-15/16”
Trane
6200 Troup Highway
Tyler, TX 75711
