DV water heater exhaust vent location
dfvellone
| Posted in General Questions on
I’m installing a direct vent (not power vent) storage tank water heater, and one of the options for the exhaust vent location is under the vented soffit. Though the vent location falls just within the minimum clearance requirements, am I asking for trouble with this location? This isn’t an enclosed soffit and facia, but 32” oc timberframed rafters that are individually vented.
Thanks, Daniel
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Replies
If you have soffit vents, then I'd avoid that vent location because warm and moist exhaust air will get into your attic, which you want to avoid. My preference here, even though it's probably more work to install, would be to go straight up through the roof with a thimble, then a regular weather cap on top. That gets the exhaust up above the entirety of the structure where you won't have any problems.
Bill
The soffit vent likely has more than sufficient intake at the soffit. Just block the intake at the vent. It can still look the same from the exterior.
Be careful here. If I understand correctly, it is possible that the rafter bays are vented individually and it is possible that they do not communicate with each other in a generally vented attic space. Closing off one of the soffit vents could render that entire bay unvented and could lead to moisture buildup in that bay. The same thing happens with cathedral ceilings that have closed rafter bays due to valleys, skylights, etc. While the total vent area might be sufficient, the unvented bays are still subject to condensation and moisture damage.