Goodman Furnace: Low stage pressure switch contacts not closed
Low stage pressure switch contacts not closed on a Goodman furnace: The control is looking for the low stage pressure switch to close and it isn't seeing it. That switch tells the control the inducer is pulling a draft, so without it the furnace won't go on to light. Usually it's the switch, its hose, or something in the wiring.
Applies to: 34.5 in chassis gas furnaces
Common causes of low stage pressure switch contacts not closed
- Low stage pressure switch contacts sticking
- A short in the pressure switch circuit wiring
- A cracked, pinched or plugged pressure switch hose
How to fix low stage pressure switch contacts not closed: step by step
- Inspect the pressure switch hose and repair or replace it if it is cracked, kinked or has water in it.
- Look over the pressure switch wiring with the power off for rubbed insulation or shorts.
- Repair the short in the wiring if you find one.
- Watch the switch during an inducer start and see whether it closes.
- Replace the low stage pressure switch if the contacts stick.
- Do not jumper the switch. It is a safety device.
If the unit shows an error code, look it up: Goodman Furnace codes
Source: Goodman GMVC96 Service and Troubleshooting, p. 61. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.