Goodman Furnace: Condensate drain system general rules
Condensate drain system general rules on a Goodman furnace: Rules for the condensate drain trap and field drain line.
Applies to: All furnace drain configurations
How to fix condensate drain system general rules: step by step
- Use the drain trap supplied with the furnace.
- Prime the drain trap before the first start. Both sides of the trap must be primed.
- Route the drain line to meet local and national codes.
- Slope the drain line 1/4 in per foot downward toward the drain.
- Do not trap the drain line anywhere except at the furnace drain trap.
- Protect the drain line from freezing where it runs through cold areas.
- With an AC coil on a common drain, install an open tee near the coil to relieve positive pressure.
- Vent a common drain with an open tee no higher than the bottom of the collector box.
- Vertical installs: AC coil condensate may drain into the furnace trap only if a trap sits between the coil and furnace trap and the drain does not end below the furnace trap water level.
Safety: Gas, electrical and refrigerant work must be done by a licensed technician. Turn off power and gas before servicing, never bypass a safety control, and always follow the manufacturer's manual for your exact model.
If the unit shows an error code, look it up: Goodman Furnace codes
Source: Goodman GMVC96 service manual, p. 19-20. 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.