Other Unit Adjustments
Primary Limit.
The primary limit is located on the heating compartment vestibule panel. This limit is factory set and requires no ad justment.
Flame Rollout Switches (Two)
These manually reset switches are located on the front of the burner box.
Pressure Switch
The pressure switch is located in the heating compartment on the cold end header box. This switch checks for proper combustion air inducer operation before allowing ignition trial. The switch is
Temperature Rise
After the furnace has been started and supply and return air temperatures have been allowed to stabilize, check the temperature rise. If necessary, adjust the blower speed to maintain the temperature rise within the range shown on the unit nameplate. Increase the blower speed to decrease the temperature. Decrease the blower speed to increase the temperature rise. Failure to adjust the temperature rise may cause erratic limit operation.
Fan Control
The fan on time of 30 seconds is not adjustable. The 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 120 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 be tween 90° and 110°F at the moment that the blower is
Electrical
1 - Check all wiring for loose connections.
2 - Check for the correct voltage at the furnace (furnace operating). Correct voltage is 120VAC + 10%
3 - Check
Motor Nameplate__________Actual__________
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.
|
|
| HEAT FAN‐OFF TIME IN SECONDS |
|
|
| |||||||||
|
|
|
|
| NO JUMPER |
|
|
|
|
|
|
|
| ||
| To adjust |
| |||||||||||||
|
|
|
|
| achieve desired setting. |
|
|
|
| ||||||
60 Second | 90 Second | 120 Second | 180 Second | ||||||||||||
off Time | off Time |
| off Time |
| off Time | ||||||||||
60 | 90 | 120 | 180 | 60 | 90 | 120 | 180 | 60 | 90 | 120 | 180 | 60 | 90 | 120 | 180 |
FIGURE 62
NOTE - Termination of any unused motor leads must be in sulated.
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 perfor mance tables.
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 igni tion failure. This type of lockout is usually due to low gas line pressure. After one hour of continuous thermostat de mand for heat, the Watchguard will break and remake ther mostat demand to the furnace and automatically reset the integrated control to begin the ignition sequence.
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 ter mination for blockages.
3 - Obstructed pipe or termination may cause rollout switches to open. Reset manual flame rollout switches on burner box assembly if necessary.
Page 44
