Never bypass pressure switch to allow furnace opera- tion. To do so will allow furnace to operate under poten- tially hazardous conditions.
Do not try to repair controls. Replace defective controls with UPG Source 1 Parts.
Never adjust pressure switch to allow furnace operation.
CONTINUOUS FLASH: This indicates that flame was sensed when there was not a call for heat. With this fault code the control will turn on both the inducer motor and supply air blower. A gas valve that leaks through or is slow closing would typically cause this fault.
2 FLASHES: This indicates that the normally open pressure switch contacts are stuck in the closed position. The control confirms these contacts are open at the beginning of each heat cycle. This would indi- cate a faulty pressure switch or miswiring.
3 FLASHES: This indicates the normally open pressure switch contact did not close at the beginning of the heat cycle. This could be caused by a number of problems faulty inducer, blocked vent pipe, broken pres- sure switch hose or faulty pressure switch.
4 FLASHES: This indicates that a primary or auxiliary limit switch has opened its normally closed contacts. With this fault code the control will operate the supply air blower and inducer. This condition may be caused by: dirty filter, improperly sized duct system, incorrect blower speed setting, incorrect firing rate or faulty blower motor.
5 FLASHES: This fault is indicated if the normally closed contacts in the rollout switch opens. The rollout control is manually reset. If it has opened, check for proper combustion air, proper inducer operation, and primary heat exchanger failure or burner problem. Be sure to reset the switch after correcting the failure condition.
6 FLASHES: This indicates that after the unit was operating, the pres- sure switch opened 4 times during the call for heat. If the main blower is in a “Delay on” mode it will complete it, and any subsequent delay off period. The vent motor continues to operate until the pressure switch
7 FLASHES: This fault code indicates that the flame could not be established. This
8 FLASHES: This fault is indicated if the flame is lost 5 times (4 recy- cles) during the heating cycle. This could be caused by low gas pres- sure or faulty gas valve.
9 FLASHES: Indicates reversed line voltage polarity. Both heating and cooling operations will be affected. Check polarity at furnace and branch.
11 FLASHES: This fault will be indicated if the rollout jumper wire con- nection soldered into the board is broken. If this fault occurs the control will have to be replaced. This fault may also occur in installations where an improper ground is present. Prior to replacing control, verify that unit is properly grounded.
STEADY ON: This fault occurs if the gas valve is energized when there is no call for heat. If this happens the vent motor is energized and will remain energized for 5 seconds or until the fault clears itself at which point the vent motor
NOTE: If a flame is detected the control flashes the LED for 1/8 of a second and then enters a flame stabilization period.
IGNITION CONTROL (P/N
Low flame signal control lockout point is
0.9 microamps DC (µa)
Thermostat Calling for Heat
(Seconds) | 0 2 | 17 | 22 | 52 |
Fan on Delay 30 Seconds
ON
THERMOSTAT
OFF
ON
INDUCER
OFF
ON
Thermostat Satisfied
0
OFF |
|
15 Sec. | OFF |
Post |
|
Purge |
|
IGNITOR OFF
MAIN VALVE
OFF
HUMIDIFIER
OFF
ELECTRONIC
AIR CLEANER
OFF
CIRCULATING
BLOWER OFF
OFF
ON
ON
OFF
ON
OFF
ON
OFF
OFF |
OFF
OFF
OFF
60, 90, 120, 180 SEC. OFF Selectable Fan Off Delay
FIGURE 8: Furnace Control Event Schedule
Unitary Products Group | 7 |
