Drip Pans

[peterk2]

During this past weekend, I have had the "pleasure" of inspecting 2 new construction jobs. Both of them had air handlers in the attic with drip pans installed. Both had no secondary drain line but had cutoff/float switches installed. I found out through Code Check that a secondary drain is not required if a float / cutoff switch is installed. I accepted that and went on my way. Then my brain kicked in. What happens to the water in the drip pan? Does it sit there? Does it slowly evaporate or worse remain at a low enough level to not trip the switch but keep a pool of festering water in there. Who the heck thought this one up?

I just can't see a tech or homeowner going up to the attic with a sponge and bucket to soak up the water in the pan. I definitely don't see them changing the filter. I mentioned all of this to my clients and hoped that they saw the light.

Peter K

Argyle Home Inspections.

[hausdok]

Hi Pete,

I should think that in weather hot enough to require the AC that the pan will eventually reach the cutoff switch even if it takes several days. When that happens, the homeowner is going to be ticked that the A/C is out when it's needed and someone is bound to check it out.

Don't feel bad. I just looked at a brand new house last week where there's an evaporator coil in an attic. No drain pan or secondary drain. Nothing but a little plastic condensate pump sitting on the drywall of the ceiling below with the clear plastic tubing threaded down through the outside walls to the outside. No 30-inch deep working space, no platform, no air gap before the trap on the condensate line to the pump, Sheesh, we see A/C so infrequently here that even the HVAC guys don't know what they're doing when they have to install one!

ONE TEAM - ONE FIGHT!!!

Mike

[mcramer]

Originally posted by peterk2

During this past weekend, I have had the "pleasure" of inspecting 2 new construction jobs. Both of them had air handlers in the attic with drip pans installed. Both had no secondary drain line but had cutoff/float switches installed. I found out through Code Check that a secondary drain is not required if a float / cutoff switch is installed. I accepted that and went on my way. Then my brain kicked in. What happens to the water in the drip pan? Does it sit there? Does it slowly evaporate or worse remain at a low enough level to not trip the switch but keep a pool of festering water in there. Who the heck thought this one up?

I just can't see a tech or homeowner going up to the attic with a sponge and bucket to soak up the water in the pan. I definitely don't see them changing the filter. I mentioned all of this to my clients and hoped that they saw the light.

Peter K

Argyle Home Inspections.

A float switch is fine. The unit won't work when the pan is full of water. The owner will call an AC guy to fix it. The water will eventually evaporate. It's no big deal.

[peterk2]

I agree with you guys. I know that the cutoff will shut the unit down. It's just that I'm a bit tired of finding shoddy work and assumptions by contractors that everything will work fine. I believe in redundancy. Most of the buyers I deal with have no building knowledge.If they don't see it, they forget about it. Then filters don't get changed, condensers don't get serviced etc. Just my two cents. Thanks for the chance to vent.

PeterK

Argyle Home Inspections

[Les]

Peter, I agree with you. Sometimes it is the common sense in us that should over-ride the "code". I would have done the same as you!

[kurt]

I'm pleased when I find a pan & cutoff switch; usually, there's nothing. No pan, no switch, no drain, no nothing.

Water doesn't "fester"; in an attic, it will evaporate in a couple days. Honest, it's OK.

If someone wants to argue that it's dipshit, I'll agree; I can't understand why anyone wouldn't run a $10 drain. But, this job is goofy enough w/out us making stuff up and establishing our own little "code requirements". What the guy did is accepted industry practice, whether we like it or not.

[Brian G]

I think a float switch is actually better (properly installed). Most people have no idea about any of this stuff to start with, so if they did happen to be wandering around in the yard and saw the auxiliary drain line dripping, they would think nothing of it. Time goes on, eventually the auxiliary drain line clogs too, and now there's a big mess on the ceiling. What good was the auxiliary line?

If the float switch shuts the system down and someone has to make the call to get a guy out to find out what the problem is, the big mess never happens. If I could change anything about that I would have them set the float switch way down the side of the pan. What's the point of waiting for it get really full before shutting down? One inch of water should do it.

I regularly find furnace/evaporator combo's in a closet in the middle of a slab house with no back-up drain line of any kind, and no way to get one to the exterior. I always recommend installing a small pan in the return air cavity with a float switch and running the auxiliary line to it. Not hard to do, but it should serve very well...no big mess. I don't know how many have followed through and done it, but that isn't my concern.

Brian G.

Floating A Suggestion [^]

[mgbinspect]

That is a good point, Brian. I whole heartedly agree with you!

Talking about "not having a clue", even rust streaks down the side of the house from the auxiliary pan don't tip a lot of people off to the fact there's a problem.

[Bob White]

My church has three air handling / evap units in the attic --- each has a pan with drain piping and a float switch.

On a Monday morning a few weeks agow, one of the units wouldn.t come on. Tuesday morning it worked fine, but staff called HVAC guy to make sure nothing major was wring. He checked it out, said drain line was clogged and that he cleared it (no charge, he's a member of church)

Friday, my wife and I were at the curch cooking apaghetti sauce and pasta all day for HeavenSkates Skate Park funding dinner / auction.

As we were closing up shop (around 10 pm that evening -- air conditioning running all day -- not norrmal for our church) someone noticed water dripping from ceiling. It was hot, humid, and there had been and were at the time torrential rains and winds. Everyone (me too -- I was tired and wanted to go home) assumed that we had a roof leak. We placed buckets under the leaks and locked up and went home.

DUH

It was the same drain pan. The drain piping had closed again due to algae, and this time the float switch didn't float.

Saturday morning there was gypsum board, insulation, and lots of water in our fellowship hall floor and splattered along the walls.

So --- Even if you have the drain piping AND the float switch in place, if your homeowner doesn't keep the system maintained, their ceiling (and floor) is likely to get wet.