ERROR STATUS
To troubleshoot the system where error status is
indicated:
•
If an outdoor temperature sensor is not used:
— First check to ensure that the OUT terminals are
properly shorted together.
— Then cycle power to the device. If the control con-
tinues to flash in the error mode, replace the
humidity control.
• If an outdoor temperature sensor is used, disconnect
it, short the OUT terminals together and cycle power.
If the error status remains, replace the humidity
control. If the error status is eliminated, replace the
outdoor temperature sensor.
Control enters the error mode if any sensor reads out-of-
range. See Table 3.
Table 3. Error Modes.
Sensor
Indoor temperature
RH sensor
Outdoor
temperature
OUT terminals
CHECKOUT
NOTE: The furnace blower must be on for the humidi-
fier to operate (does not apply to steam humidi-
fier applications).
Resistance (K ohm)
Temperature (°F)
Temperature (°C)
Error Indicated When . . .
Temperature reads below 45°F
or greater than 120°F.
RH reads 0 or 100%.
Temperature reads less than -
40°F or greater than 120°F.
At powerup, if sensor is present
and later opens or shorts.
At powerup, if sensor terminals
are jumped and later are open.
Table 4. Sensor Resistance at Various Temperatures.
333
99.2
74.3
-40
-4
-40
-20
-15
H1008A,D AUTOMATIC HUMIDITY CONTROL
IMPORTANT
— When an outdoor sensor is not installed, there
may be a delay in humidification, caused by the
method used to determine outdoor temperature
conditions.
— If the furnace is off for more than 24 hours or the
outdoor temperature sensor reads greater than
63°F, the control enters an auto off mode where
it does not allow humidification until the furnace
cycles or the outdoor temperature drops below
60°F.
— This auto off mode prevents the humidifier and
air conditioner from running simultaneously.
— The control may enter dehumidification mode if
the house dewpoint rises above 58°F.
Outdoor Temperature Sensor Checkout
Check the thermistor sensor by comparing its resistance
to the temperature as measured by an accurate
thermometer. The resistance of the thermistor sensor
increases as its temperature drops. Table 4 shows
approximate sensor resistance values at various
temperatures.
Test Mode
Use the following procedure to place the control in the
test mode and call for humidification/dehumidification:
1. Turn the frost factor setpoint dial to the Test
position.
2. Do one of the following:
a. At the thermostat, with the system switch set to
b. Set the System switch to Off and the Fan
3. Verify humidifier and/or dehumidifier/ventilation
unit is activated.
In the test mode, the indicator light remains on
continuously with a call for heat or fan; otherwise, it
remains lit for four seconds and turns off for one second.
This flashing sequence continues until the control is
taken out of the test mode. After thirty minutes, the
control automatically resets to the maximum frost factor
setting. If system checkout is not completed within thirty
minutes, the test mode can be extended by turning the
dial back to one of the dial settings and then returning it
to the test mode. After the system has checked out,
return the control to the desired frost factor setting. See
the Adjustment section.
56.1
32.9
5
14
32
-10
0
7
Heat and the fan switch to Auto, move the tem-
perature setpoint about 10°F (6°C) above the
room temperature to call for heat, or
switch to On for continuous fan operation.
19.9
12.5
10.0
50
68
10
20
8.04
6.5
77
86
9.5
25
30
3.5
69-1185EF-3