Allied Air Enterprises 95G1UH, A95UH, A93UH, 92G1UH Heat FAN-OFF Time Seconds

Other Unit Adjustments

Primary Limit

The primary limit is located on the heating compartment vestibule panel. This limit is factory set and requires no adjustment.

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 factory set and must not be adjusted.

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 heat 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 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 56.

HEAT FAN-OFF TIME SECONDS

To adjust fan-off timing, reposition jumper across pins to achieve

desired setting.

Figure 56

Thermostat Heat Anticipation

Set the heat anticipator setting (if adjustable) according to the amp draw listed on the wiring diagram that is attached to the unit.

Electrical

1.Check all wiring for loose connections.

2.Check for the correct voltage at the furnace (furnace operating).

3.Check amp–draw on the blower motor.

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 control board 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 Blower performance data beginning on the next page.

6.Connect selected speed tap at control board speed terminal.

7.Re-secure 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.

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 switches to open. Reset manual flame rollout switches on burner box assembly if necessary.

506501-01 Issue 1031 Page 41 of 48