Condensate pump in the attic

First time I’ve seen this in 4 years. Last week I saw it twice. HVAC condensate pumps in the attic. Neither had the pump in a drip pan. Bad idea? Poor design? What are your thoughts?

This is what I said about it:

“Condensation from the attic unit evaporator coil is pumped to the exterior. Although this may be permissible, we consider it to be a poor design. It is highly unusual and rarely seen. This mechanical pump will eventually fail and when that happens the reservoir may overflow and may damage the ceilings below, particularly if the pump is not in the drip pan or wired to shut down the HVAC system. We recommend that this installation be evaluated by a licensed and competent HVAC contractor and replaced with a conventional gravity flow condensate drain if practical.”

Some of those pumps (maybe all) have a float (or some other means) to disable the furnace when the resivour fills too much. I comment on whether it looks like it is set up to do that (extra thermostat type wires going back to the furnace) or not. They can also install a floodstop device if the pump does not have the shut-off capability.

Edit: Here is a link to a pump. It looks like the overflow switch is an option.

Hello Joe,
Condensate pumps on the upper floors pumping “downward” is a waste of resources.

The location of the pump (which is susceptible to failure) is a consideration when located above the finished space.

The condensate pump shut off control should be employed to shut down the HVAC system “when” failure occurs.

One thing you didn’t mention was if there was a safety switch on the drip pan. There should also be a switch located here (wired in series). Condensate pump failure is not the only cause of condensate flooding.

I don’t necessarily agree with calling for further evaluation (as this condition is no more catastrophic than any other configuration without a specific code requirement). I would recommend “monitoring the condition”. If the client is concerned, they can change it. [size=2]You’re covering all the bases, I just report things a little differently.


Was the pump in the attic alongside the air handler? If so, I don’t see an issue with this set-up. I look for a pump, a secondary pan with a hard-wired flood stop device (there are many) which is designed to detect water in the secondary pan and will automatically shut down the air handler if it senses water in the secondary pan.

You mean this pan?

091008 122.JPG 091008 121.JPG[/size]

091008 121.JPG

091008 121.JPG

I can see that the flood stop device is wired (second pic) but seeing that the secondary pan drain hole will allow all condensate to drain onto the ceiling below. This simply needs a drainage pipe installed which will run out into the soffit area.

David, thanks for all your help. Shouldn’t the pan be moved over a tad? Seems like it’s right even with the evaporator coil seam.


If the secondary pan is smaller than the unit itself, the pan should be upgraded to be the same size or a tad larger than the unit that it is under.

I’d rather see the pan sized accordingly rather than moving it and taking chances on the drip location. Condensate will drip at all locations (from the primary pan area) and having the secondary pan sized accordingly will alleviate unexpected drips onto the ceiling below.