Condensate vent?

[MeDesignEng]

Im designing a walk in cooler and freezer and I have the condensate from each drained to a near by mop sink. Do I need to vent these lines?

 

[quark]

Your drain pan is already at atmospheric pressure. So, no need for any vents. Just provide a U loop and that is all.

 

[sterl]

The sink may normally be at atmospheric pressure but the evaporator's drain pan is nowhere near...Unless there's full bladder area equalizer on the walk in freezer.

And then there's gonna be the day when somebody fills the sink full, then pulls the plug and the drain line is effectively at 2-psi over top of water pressure...

This one wants deep fully reversed traps and potentially trap primers. If the evaps and their pan connects are not high enough to tolerate that plumbing it gets a little more interesting.

 

[RossABQ]

I'm not seeing a problem; the drain line needs to have a minimum of a 1" air gap above the highest possible water level of the mop sink, tho, per codes. (Just to be clear, this is a floor sink, not a laundry tub, right?)