Goodman furnace E2: Low stage pressure switch stuck open
E2 means the inducer ran and the low stage pressure switch never closed, so gas was never released. It is the most common fault on high-efficiency furnaces, and the cause is often outside the house.
Applies to: Goodman GMVC96, GMVM97, GCVC96, GCVM97 and Amana AMVC96, AMVM97 series gas furnaces with a two-character alphanumeric display.
What it means
At the start of a heating cycle the control runs the draft inducer and waits for the pressure switch to close, confirming enough air is moving to carry combustion products safely out. If it does not close in the allowed time, the sequence stops before the gas valve opens. Everything in the venting path can produce this: a blocked intake or exhaust, a full condensate trap, a weak inducer, a disconnected hose. It is also the fault most often caused by something entirely outside the furnace — a vent termination blocked by snow, ice, leaves, or a nest. That makes the first useful check a walk outside rather than anything in the basement.
Most common causes
- A blocked exhaust or intake pipe at the outside termination — snow, ice, leaves, insect or rodent nests.
- A condensate drain or trap that is full or blocked, so water sits where the draft should be.
- The sensing hose disconnected, cracked, kinked, or holding water.
- A weak or seized draft inducer, or a loose inducer wheel, so the required suction is never produced.
- The pressure switch itself failed and no longer closing at its rated pressure.
- Vent piping too long, with too many elbows, or the wrong diameter for the furnace's input.
- High wind at the termination briefly disturbing the draft on some installations.
How to diagnose it
- Look at the outside vent termination first. It is the highest-yield check on the list and needs no tools.
- Listen for the inducer. If it does not run at all, the fault is upstream of the switch; if it runs and nothing follows, the switch is not seeing the draft.
- Check the condensate drain and trap for standing water, and look for water anywhere it should not be inside the cabinet.
- Note the weather. This appearing during the first hard freeze or a snowstorm points strongly at the termination.
- Check whether anything has recently been built, stored, or planted near the outside vent.
How to fix it
- Clear the vent termination if it is blocked, and keep both pipes clear of snow, ice, and vegetation. Check after heavy weather.
- Clear a blocked condensate drain — reasonable homeowner work on most installations.
- The pressure switch, its hose, the inducer, and the vent system inside the cabinet are technician work.
- If the vent piping is undersized or over-length for the furnace, have it corrected rather than worked around. A furnace that only just proves draft will fault intermittently for years.
- Never bypass the pressure switch. A blocked flue with a firing burner is how carbon monoxide gets into a house.
Notes
If this appears on the coldest night and clears on a milder day, suspect ice at the vent termination rather than a failed part. High-efficiency furnaces produce condensate at the exhaust, and it can freeze around the pipe and progressively close it.
Related
All codes for this manufacturer
Goodman and Amana furnace fault codes — every code, with what differs between models.