Package Unit: GPG13

Re: Code 2

CODE 2 = Pressure switch "Open" with the inducer motor energized.

CHECKOUT:

1. Check Heating Sequence

• Energize a call for heat from the thermostat.
• Ensure that the inducer motor starts.
  • No Inducer + Code 2 → Step 2. Check Control Board/Relay
  • Inducer Starts + Code 2 → Step 4. Check Pressure Switch

2. Check Control Board / Relay

• Check for 24VAC between "W' and "C" on the control board.
  • No Power on "W" = No Call for Heat
• (GPG24, 30, 36, 42) Check for 230VAC between Ignition Control Board [D1] terminal (RED) and Ignition Control Board [L2] (PRP).
  • Power Present → Step 3. Check Inducer
  • No Power + Code 2 = Bad Ignition Control Board
• (GPG48, 60) Check for 230VAC between Vent Motor Relay terminal# 2 (RED) and Compressor Contactor L2 (PRP).
  • Power Present → Step 3. Check Inducer
  • No Power + Code 2 ⇒ Check for 230VAC between Vent Motor Relay coil terminals #1 (WH) #3 (BL).
    • Power on VMR Coil + No Power on terminal #2 = Bad Vent Motor Relay
    • No Power on VMR Coil = Bad Ignition Control Board 

3. Check Inducer

• Check the temperature of the inducer motor.
• Use an Amp Probe to check the amperage of the inducer motor.
  • 230V Power + Hot Motor + No Amperage = Off on Overload ⇒ Turn off power to the unit, check to see if the inducer motor turns freely, allow motor to cool, then recheck.
  • 230V Power + Cool Motor + No Amperage = Bad Inducer Motor
  • 230V Power + Amperage + Not Running = Bad Inducer Motor or Item Stuck in Inducer Wheel ⇒ Remove Inducer Assembly & Check Wheel

4. Check Pressure Switch

• Check for 24VAC between each side of the pressure switch (YEL) to "C" of the Ignition Control Board.
  • Power on Both Sides of the Switch + Code 2 = Bad Ignition Control Board
  • Power on One Side of the Switch Only = Open Pressure Switch
    • Use a pressure gauge to check the negative pressure from the inducer and compare to the pressure switch rating.
      • Adequate Negative Pressure = Bad Pressure Switch
      • No or Low Negative Pressure ⇒ Remove the inducer assembly, check the condition of the Inducer Blower Wheel, also check for a Clogged Pressure Port