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6 FLASH: This indicates that after the unit was operating, the pressure 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 induced draft motor continues to operate until the pressure switch
7 FLASH: This fault code indicates that the flame could not be estab- lished. This
CAUSE: This may be caused by low gas pressure, faulty gas valve, faulty hot surface ignitor or burner problem.
8 FLASH: This fault is indicated if the flame is lost 5 times (5 recycles) during the heating cycle.
CAUSE: This could be caused by low gas pressure or faulty gas valve.
9 FLASH: Indicates reversed line voltage polarity. Both heating and cooling operations will be affected. Check polarity at furnace and branch.
11 FLASH: This fault will be indicated if the rollout jumper wire connec- tion soldered into the board is broken. If this fault occurs the control will have to be replaced.
STEADY ON: This fault occurs if the gas valve is energized when there is no call for heat. If this happens the induced draft motor is energized and will remain energized for 5 seconds or until the fault clears itself at which point the induced draft motor
CAUSE: This failure is counted as a recycle. Check the gas valve and control for proper operation.
IGNITION CONTROL
Normal flame sense current is approximately
3.7 microamps DC (µa)
Low flame signal control lockout point is
0.9 microamps DC (µa)
FIGURE 14: Furnace Control Event Schedule
Unitary Products Group | 9 |