27
O
F
F
O
F
F
8 7
4 3 2 1
O
F
F
O
N
4 3 2 1
O
N
O
F
F
4 3 2 1
O
N
O
N
4 3 2 1
Cooling
Speed
Tap A
Cooling
Speed
Tap B
Cooling
Speed
Tap C
Cooling
Speed
Tap D
*
Cooling Speed Taps
(
*
indicates factory setting)
O
F
F
O
F
F
8 7
4 3 2 1
O
F
F
O
N
8 7
4 3 2 1
O
N
O
F
F
8 7
4 3 2 1
O
N
O
N
8 7
4 3 2 1
Heating
Speed
Tap A
Heating
Speed
Tap B
Heating
Speed
Tap C
Heating
Speed
Tap D
Heating Speed Taps
(
*
indicates factory setting)
*
O
F
F
O
F
F
8 7
4 3 2 1
O
F
F
O
N
8 7
4 3 2 1
O
N
O
F
F
8 7
4 3 2 1
Normal
+ (Plus)
Adjust
- (Minus)
Adjust
Adjust Taps
(
*
indicates factory setting)
*
8 7
8 7
8 7
A
DJUST
B
LOWER
H
EAT
O
FF
D
ELAY
The integrated control module provides a selectable heat off delay
function. The heat off delay period may be set to 90, 120, 150,180
seconds using the DIP switches or jumper provided on the control
module. The delay is factory shipped at 150 seconds but may be
changed to suit the installation requirements and/or homeowner
preference. Refer to the following figures for switch positions and
corresponding delay times.
Heat Off
Delay
90 Seconds
ON
ON
1
2
3
Heat Off
Delay
120 Seconds
Heat Off
Delay
150 Seconds
Heat Off
Delay
180 Seconds
ON
OFF
1
2
3
ON
1
2
3
1
2
3
OFF
OFF
Heat Off Delay
(* indicates factory setting)
*
OFF
Heat Off Delay S
C
IRCULATOR
B
LOWER
F
AN
T
IMING
A
DJUSTMENT
NOTE:
Items in this section refer to the
air circulator blower fan
,
NOT to the induced draft blower. The induced draft blower timing
sequence is not adjustable. The circulator blower fan timing is
adjustable only on models with optional “heating fan OFF delay”
adjustment pins or switches (Figure 28). It is NOT adjustable in
any other circumstances.
As shipped, the circulator blower fan will remain on for 150 seconds
after the gas valve closes. The circulator blower then ramps down
to “OFF” during the 30 seconds following the heat off delay period.
When a call for cooling occurs, the circulator fan comes on and
remains on for 45 seconds after the call for cooling ends. During
normal heating operation, the circulator fan will come on
approximately 37 seconds after the gas valve opens.
O
N
O
F
F
O
N
O
F
F
O
N
O
F
F
O
N
O
F
F
1
2
1
2
1
2
1
2
90
SE C ON D
D EL AY
120
SE C ON D
D EL AY
150
SE C ON D
D EL A Y
180
SE C ON D
DE LA Y
Switches viewed in an upflow installation.
Adjustment Switches
XIII. OPERATIONAL CHECKS
WARNING
T
O AVOID PERSONAL INJURY OR DEATH, DO NOT REMOVE ANY INTERNAL
COMPARTMENT COVERS OR ATTEMPT ANY ADJUSTMENT.
E
LECTRICAL
COMPONENTS ARE CONTAINED IN BOTH COMPARTMENTS.
C
ONTACT A
QUALIFIED SERVICE AGENT AT ONCE IF AN ABNORMAL FLAME APPEARANCE
SHOULD DEVELOP.
B
URNER
F
LAME
The burner flames should be inspected with the burner compartment
door installed. Flames should be stable, quiet, soft, and blue (dust
may cause orange tips but they must not be yellow). Flames should
extend directly outward from the burners without curling, floating,
or lifting off. Flames must not impinge on the sides of the heat
exchanger firing tubes.
Check the burner flames for:
1. Good adjustment
2. Stable, soft and blue
3. Not curling, floating, or lifting off.
Burner Flame
A
UXILIARY
L
IMIT
C
ONTROL
Auto reset limits are located on or near the blower. To access this
auxiliary limit, disconnect the electrical power and remove the blower
door. If the limit control opens, the air circulation blower will run
continuously. The diagnostic light will flash one time. The auxiliary
limit control is designed to prevent furnace operation in case of
main blower failure on horizontal and counterflow installations. It
may also open if the power supply is interrupted while the furnace
is firing. The auxiliary limit control is suitable for both horizontal
right and horizontal left installations. Regardless of airflow direction,
it does not need to be relocated.
WARNING
T
O AVOID PERSONAL INJURY OR DEATH, DO NOT REMOVE ANY INTERNAL
COMPARTMENT COVERS OR ATTEMPT ANY ADJUSTMENT.
E
LECTRICAL
COMPONENTS ARE CONTAINED IN BOTH COMPARTMENTS.
T
O PREVENT
PROPERTY DAMAGE, PERSONAL INJURY OR DEATH DUE TO EXPLOSION
AND/OR FIRE, CONTACT A QUALIFIED SERVICE AGENT AT ONCE IF AN
ABNORMAL FLAME APPEARS.
