Goodman Furnace: Customer bundle: auxiliary condensate switch wiring
Customer bundle: auxiliary condensate switch wiring on a Goodman furnace: Aux alarm input on the GMVC96 family control. It's meant for a condensate switch, and compatible CO2 sensors or fire alarms can use it too. Switch is normally closed. Opens on high water, control shuts the furnace down.
Applies to: Furnace with Aux alarm input
Common causes of customer bundle: auxiliary condensate switch wiring
- Condensate switch open because the drain is backed up
- Switch wired to the wrong terminal or wire loose
- Switch itself failed open
How to fix customer bundle: auxiliary condensate switch wiring: step by step
- Confirm the switch is landed on the Condensate terminal.
- Confirm the switch is normally closed. It opens when the evaporator base pan water level is too high.
- If the switch is open, check the condensate drain first. Look for a plugged line or trap.
- Clear the blockage, let the pan drain, then see if the switch closes again.
- With power off, check the switch for continuity by meter. Open with a dry pan means a bad switch.
- Check the connections at the terminal for looseness.
If the unit shows an error code, look it up: Goodman Furnace codes
Source: Goodman GMVC96 service and troubleshooting manual, p. 32. 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.