Remove the cover and inspect the drain for debris.
Condensation line joined to house vent in attic.
In this quick video i show you what to look for if you have condensation build up in your attic.
It may be located directly under the indoor air handler in your attic or utility closet.
In an attic like this wintertime ceiling condensation can form when cold air from the attic hits your warm ceiling.
In summer when the air conditioning is on the reverse happens.
The vent opening should always rise above the trip level of the condensate overflow switch when it is in the primary drain line or pan or above the secondary aux overflow port on the primary drain pan.
They are prone to building up condensation.
Check all possible entry points for water leaking from outsi.
It may be covered by a removable access panel.
How to prevent condensation in ceiling vents.
If it just drains outside to building exterior your probably don t need a trap or vent but do make sure it has adeq.
Try to identify the access point on the drain line which might be a t shaped vent with a pvc cover.
Most building codes don t address humidity issues and are also pretty lax on the level of insulation required in your attic especially around those previously mentioned attic bypasses.
If the drain line is connected to a plumbing drain leading to sewer it should have a trap and a downhill vent.
Newer homes can be affected as well.
Improving your attic s air sealing and insulation prevents attic air from reaching your ceiling and it s a fairly easy job to do yourself.
Also attic condensation isn t a problem limited to only older homes.