Condensate drain is clogged. On a horizontal attic unit the secondary pan overflows into the ceiling below and you find it as a stain. Try clearing the line at the cleanout with a wet vac before calling – it is often a five minute job.

This is most common in homes built roughly 1980 to 2000. The polybutylene and aluminum-wiring window, 150 amp panels, R-22 systems and first-cycle architectural shingle.

You can handle this one yourself. No call needed.

Related

• Ductwork threaded through a house built for floor grates
• One central return for the whole house
• Water heater vents into the chimney and the furnace no longer does
• Silver-wrapped tape on old duct joints
• Additions still on window units
• Uninsulated walls and an oversized condenser
• Furnace runs but the house never warms evenly
• Electrical panel cannot support a modern condenser

Back to Hvac.

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Written by Jaylan Jones. I Like To Fix earns a referral fee when a call connects to a contractor. See our business-model disclosure.