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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 ap-
plications. 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 pro
-
vide lower return air temperatures; shorter settings pro-
vide 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.
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.
HEAT FAN
‐
OFF TIME IN SECONDS
To adjust fan-off timing, reposition jumper across pins to
achieve desired setting.
NO JUMPER
60 90
120 180
60 90
12
0
180
60 90
12
0
180
60 90
12
0
18
0
60 Second
off Time
90 Second
off Time
120 Second
off Time
180 Second
off Time
Figure 63
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 automat-
ic 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.
Service
WARNING
ELECTRICAL SHOCK, FIRE,
OR EXPLOSION HAZARD.
Failure to follow safety warnings exactly could result in
dangerous operation, serious injury, death or property
damage.
Improper servicing could result in dangerous operation,
serious injury, death, or property damage. Before
servicing, disconnect all electrical power to furnace.
When servicing controls, label all wires prior to
disconnecting. Take care to reconnect wires correctly.
Verify proper operation after servicing.
WARNING
The blower access panel must be securely in place when
the blower and burners are operating. Gas fumes, which
could contain carbon monoxide, can be drawn into living
space resulting in personal injury or death.
Annual Furnace Maintenance
At the beginning of each heating season, and to comply
with the Lennox Limited Warranty, your system should be
checked as follows:
NOTE - Burner inspection and service is not recommend-
ed for annual furnace maintenance.
1 -
Check wiring for loose connections, voltage at
indoor unit and amperage of indoor motor.
2- Inspect all gas pipe and connections for leaks.
3- Check the cleanliness of filters and change if
necessary (monthly).
4-
Check the cleanliness of blower assembly and
clean the housing, blower wheel and blower motor if
necessary .
5- Inspect the condensate drain and trap for leaks and
cracks. Check any additional traps such as in the
crawl space exhaust. The drain and trap must also
be cleaned and the trap must be primed with water.
