Goodman · Furnace troubleshooting
Front cover pressure switch tube relocation (horizontal, left side down)
What is going on
On a Goodman GMVC96 laid horizontally with the left side down, the front cover pressure switch tube has to be moved to the lower port on the collector box cover. If you leave it where it was, the switch can end up reading a water-filled port. It is a small job once you have the parts in hand.
Likely causes
- Tube left on the upper port after a left-side-down horizontal install
- Rubber plug not moved from the bottom to the top collector box port
- Tube too long and kinked after routing
Check in this order
- Remove the tube from the front cover pressure switch and the collector box cover.
- Move the rubber plug from the bottom collector box port to the top port.
- Take the 24 in. x 1/4 in. tube from the bag assembly.
- Connect one end to the front cover pressure switch.
- Route the tube to the lower port on the collector box cover and cut off the extra length.
- Check the tube has no kinks or sags where water can sit.
Applies to: Horizontal left side down installations
More furnace guides
- Airflow lower than demanded, furnace runs on low stage when high stage is expected
- Alternate combustion air opening (upflow or horizontal)
- Alternate vent/flue location (upflow or horizontal left)
- Annual inspection checklist
- Auxiliary limit control (location and purpose)
- Auxiliary limit switch open (blower compartment)
Take it to the job
All guides, error codes and tips work offline in the HVACopedia app.
Source: Goodman GMVC96 service and troubleshooting manual, p. 9. Written in our own words; check the manual for your exact model.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.