Roof Vent Condensation Trap

This works when the vent cap is faced at downward angle.

Roof vent condensation trap. If you answered yes you may think it s due to a leaky roof but the chances are you may have a condensation issue instead. Ever since i moved in nearly 19 years ago when the temperature drops into the middle 20s or below at night and rises only barely above freezing during the day i have condensation dripping from the range hood fan. Overview the pvc termination vent was patented and designed with unique drain line opening on the side of the vent that allows water condensation to drain from the pipe. Here is our finished product.

150mm condensation trap for fitting in vertical rigid pvcu pipe ducting. The weight of the water in the trap is enough to prevent this while still allowing condensation to flow freely. Nail the lower corners with roofing nails and tar the heads. The solution to roof blisters seems to lie in improved roofing materials.

While most manufacturers don t specify this on this gravity ductless drains it is something to look out for. These roof blisters are not related to moisture trapped within the roof insulation the space that these roof vents are theoretically designed to ventilate. This should then be connected to a suitable soil vent pipe using 21 5mm overflow pipe. Not suitable for use with flexible ducting.

The lower half of the flange sits on top of the shingles. Fitted with 20mm pipe connection for running off condensate. You have just re shingled your roof and discover a leak shortly afterward. Apply a bead of asphalt roof cement on the bottom of the vent.

Traps vents the imc states that condensate drains should be trapped according to manufactures specs however wording was added in imc 307 2 4 1 that states that ductless systems must either have a check valve or a trap in the condensate line. I know this is condensation because no water drips during rain storms or even after snow storms unless it is cold. Must be used where pipe ducts pass through unheated roof voids. Slide the vent under the shingles so they cover the top half of the vent flange.

Another key component of a p trap is an air vent the air vent prevents the drain that comes after the p trap from siphoning the water in the trap out. Also known as inverted bucket steam traps these provide near continuous discharge to accommodate high condensate levels. The important dimensions for a p trap are. The leaks get worse as the temperature drops.

Systems using roof vents or ducting rising vertically carrying extract air to outside benefits with the use of a condensate trap this is to prevent any moisture forming inside the ductwork dropping back down and into the fan unit. Condensation trap for 150mm rigid duct.