Condensate drainage system check

What is going on

On these condensing Goodman furnaces the drain tubes, trap and field drain line need to be checked every year and cleaned as often as needed so condensate can leave freely. This is a job for a qualified servicer. Before opening anything, shut off power to the furnace so a pressure switch or inducer cannot start during the work.

Likely causes

• Blocked drain tubes or trap from sludge and debris, which backs water up into the furnace
• Blocked field supplied drain line, often from sediment, algae or a pinched or sagging run

Check in this order

1. Turn the power off at the disconnect before disconnecting any drain hose.
2. Check the drain tubes, trap and field drain line for blockage.
3. Clean the drain tubes, trap and drain line as needed, and refit them correctly.
4. Check for leaks at the hose connections at and inside the furnace.
5. After reassembly, restore power, run a heat cycle and watch the drain to confirm it flows and nothing weeps.
6. If the furnace has been shutting down on a water level problem, tell the homeowner it is a yearly maintenance item.

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)