Condensate Pump vent pipe

Lensworth_2

Lensworth

Condensate Pump vent pipe

A colleague of mine has been asking around the office about a condensate vent piping configuration he noticed in the field. His picture (see attached) showed a vent routed up from the condensate pump along a wall (about 8 feet), turning and coming back down and spilling to a drain. The question was about a tee that was at the lower part of the vent that connected the rising and dropping sides of the vent pipe. I have the picture attached as it is difficult to describe. There appears to only be a union in the short section of pipe. Anyone have a clue why this was piped up in this configuration?

Brad White

If I gather this correctly

the pipe connecting to the receiver is on the right, rises up to a loop then back down on the left side. Then there is that cross-over with the union.

Functionally, I see this as similar to our standard detail, with the cross-over acting as an overflow (just above the receiver top).

The vent part (not like our standard detail) serves as a siphon or vacuum break. It would let air in to relieve the displacement formed when the pumps run to empty the receiver but would also (in my estimation) force any "flash" steam or stray vapor from getting into the room. It would force it to condense within the inverted "U" vent and spill to the floor all while serving the vent/vacuum break function for the pumps.

That is my take anyway.

Overall, I like it and may consider it for our standard detail. In some buildings where we cannot vent to atmosphere and have to vent within the mechanical room, this makes a lot of sense. I learn every day here.

Brad