Auxiliary Condensate Drain Requirements

[bldengr]

What are the requirements for the auxiliary condensate drain (not the emergency overflow pan drain) on a residential heat pump air handler and where are these requirements documented?

Most installations I see have the auxiliary condensate drain connection hole on the unit plugged. If the drain is required to be piped out of the building, can it be hooked up to the primary drain line or is a separate line required? Is the drain required to have a trap the same as the primary condensate drain line?

 

[imok2]

bldengr
You would notice that if the AC unit is in a place where condensation could drip on sensitive objects(people, computers, etc) that the aux drain would be used and it would have it's seperate drain line. Think of it like a double hull ship...if a leak develops in the main drain pan or a stoppage, it will overflow into the aux pan and "voiala' all is safe

 

[imok2]

More information:

If it is absolutely necessary to install the evaporator coil in the attic space or above finished ceilings, several precautions must be taken. Major building codes require one of three steps be taken if the evaporator coil is installed in these locations. These are:
1. Install a second auxiliary condensate pan with a separate condensate line below the unit.
2. Install a secondary overflow condensate line from the unit's condensate pan.
3. Install a second auxiliary condensate pan with no condensate line and with a water-level sensing device that would shut down the unit if a certain water level was detected.

 

[wilg]

My best guess is...
Thier are no requirements for a so called auxiliary condensate drain, if most installations that you have seen are plugged it's because the extra drain
connection has been provided for installations requiring spatial geometric interference problems,(an easier spot to connect to, or maybe the ("auxilliary&quot drain is at a higher or lower elevation on the pan,which would tell me that a higher or lower static pressure for a deep seal trap is required or vica versa.
I'll check my BOCA codes, but on any industrial units
that I have seen,I've never heard of an auxiliary condensate drain connection being installed,unless so much condensate is expected to come off the coil that you need two drains.
I have heard of emergency drain pans but not auxiliary condensate drain connections being connected. All units in our plant only have one condensate drain connection.

 

[imok2]

wilg
Did he mention Industrial units? My impression was that he was talking about resedential units. oh, and there are requirements on these units in major building codes and even if there weren't it's a commen sense issue...you think!

 

[wilg]

imok2...
bldengr asked "where are these requirements
documented?"
You have now stated that "there are requirements on
these units in major building codes", so why
don't you tell him where these codes are ?
And by the way "commen sense" is spelled
common sense.