What is the purpose of the trap on the drain line?

[west_seth]

What is the purpose of the J trap or P trap <?> that HVAC techs. put on the condensation line from the air handler?

Thanks. And just curious I have one but just wondered what purpose it serves.

[Wild Leg]

Same as the trap under your sink.

They're to prevent sewer gases from infiltrating your house.

Especially if you have a draw-through evaporator.

[BobbyBJr]

The trap is to prevent the blower from pulling air up the drain line and holding water in the air handler. Without the trap, a drain on the negative side of the blower will only drain when the blower stops.

Bobby

[Swampfox]

Originally posted by bwal2
Same as the trap under your sink.

They're to prevent sewer gases from infiltrating your house.

Especially if you have a draw-through evaporator.

You run condensate lines into the sewer line?

They break the vacuum created by the blower, or, in the case of a blow thru coil, prevent conditioned air from escaping through the drain line

[Wild Leg]

Originally posted by swampfox
You run condensate lines into the sewer line?

When code requires it.

It does here.

[HVAC Pro]

Not sure who posted this link on here before, but I saved it for times like this. Happy reading.

http://www.trane.com/commercial/issues/iaq/iaq5.asp

[Wild Leg]

Originally posted by HVAC Pro
Not sure who posted this link on here before, but I saved it for times like this. Happy reading.

http://www.trane.com/commercial/issues/iaq/iaq5.asp

That was me.

I forgot where I put that!

[HVAC Pro]

Glad I posted it then. It is informative.