Water In Smoke Detector

Mozart Maestro

A customer called us about a smoke alarm going off in a home in Chicago that they purchased from us earlier this year. When they took the detector down, about 1/4 cup of water came out of the detector. The detector is on a vaulted ceiling in the second floor master bedroom.

The conduit serving this detector runs through unconditioned attic space. My hunch is that warm air is entering the box and condensing inside the conduit and flowing back down the pipe and dripping onto the detector.

One thought that is bugging me is why this is not occurring with the second smoke detector. The second unit has a vertical stub up into the attic and it connects the first unit. The second unit is outside a hall bathroom.

The R-38 insulation above the detector is dry; so I do not think there is a roof leak. The exhausts for the bathrooms and laundry are vented outside. There is an insulated HVAC duct close to the box for the detector.

I can't think of other possible moisture sources. My thought is to insulate the conduit to reduce the risk of condensation.

acrwc10

Or the water could have been in the pipe for a long time and just showed up as a problem now. for the AC line to be creating that much condensation inside of the EMT you would have other water issues showing up elsewhere in the attic.

walkerj

Should have used romex

JohnJ0906

300.7(A) You didn't/don't install seals?

__________________
John from Baltimore
"One Day at a Time"
All replies based on the 2008 NEC

Mozart Maestro

Thanks for the insight.

The customer sent me an e-mail that more water came from the box since Friday.