507762-01
Issue 1907
Page 44 of 46
Electrical
1. Check all wiring for loose connections.
2. Check for the correct voltage at the furnace (furnace
operating). Correct voltage is 10%.
3. Check amp-draw on the blower motor with blower
access panel in place.
Unit Nameplate____________ Actual_____________
Exhaust and Air Intake Pipe
1. Check exhaust and air intake connections for tightness
and to make sure there is no blockage.
2. Is pressure switch closed? Obstructed exhaust pipe
will cause unit to shut off at pressure switch. Check
termination for blockages.
3. Obstructed pipe or termination may cause rollout
switch to open. Check termination for blockages.
Fan Control
Fan On Delay
The heat fan on time of 30 seconds is not adjustable. The
cool fan on delay is 2 seconds and not adjustable.
Fan Off Delay
The heat fan off delay (amount of time that the blower
operates after the heat demand has been satisfied) may
be adjusted by changing the jumper position across the
five pins on the integrated control. The unit is shipped
with a factory fan off setting of 90 seconds. The fan off
delay affects comfort and is adjustable to satisfy individual
applications. Adjust the fan off delay to achieve a supply
air temperature between 90° and 110°F at the moment
that the blower is de-energized. Longer off delay settings
provide lower return air temperatures; shorter settings
provide higher return air temperatures. See Figure 63.
The cool fan off delay (amount of time that the blower
operates after the cool demand has been satisfied) is 45
seconds and not adjustable.
To adjust fan-off timing, reposition jumper across pins to
achieve desired setting.
NO JUMPER
60 90
120 18
0
60 90
12
0
180
60 90
120 180
60 90
12
0
180
60 Second
off Time
90 Second
off Time
120 Second
off Time
180 Second
off Time
Figure 63. Heat Fan-Off Time in Seconds
Blower Speeds
Follow the steps below to change the blower speeds.
1. Turn off electrical power to furnace.
2. Remove blower access panel.
3. Disconnect existing speed tap at integrated control
speed terminal.
NOTE:
Termination of any unused motor leads must
be insulated.
4. Place unused blower speed tap on integrated control
“PARK” terminal or insulate.
5. Refer to blower speed selection chart on unit wiring
diagram for desired heating or cooling speed. See
Product Specifications Bulletin for blower performance
data.
6. Connect selected speed tap at integrated control
speed terminal.
7. Resecure blower access panel.
8. Turn on electrical power to furnace.
9. Recheck temperature rise.
Electronic Ignition
The integrated control has an added feature of an internal
Watchguard control. The feature serves as an automatic
reset device for integrated control lockout caused by
ignition failure. This type of lockout is usually due to low
gas line pressure. After one hour of continuous thermostat
demand for heat, the Watchguard will break and remake
thermostat demand to the furnace and automatically reset
the integrated control to begin the ignition sequence.