Need Advice on Water Leaking From Air Handler

[liveanddiyinla]

Our a/c has been running more lately with the 100+ temperatures in SoCal the last couple days.

Noticed a GFCI was tripping in the restroom, same circuit as the air handler fan and thermostat. Tripped two times before I checked the air handler closet. The air handler/furnace was wet on the bottom. Looked under the air handler through the return registers and the floor was totally wet, picture attached. Luckily, this was in the evening.

Questions:
1. Any idea why this backup would cause the GFCI to trip? Maybe the filter was damp, causing the fan to work harder...What should be my first step to troubleshoot this?
2. Is the tee on this condensate drain line on the correct side? I want to know if the tee and elbow with the red arrows need to be switched.
3. Does the drain line need to have a p-trap near where it drains outside?

I cupped the tee and blew some air into the tee. The water rose close to the top and drained out the end outside. Just figured that the tee should be on the other side, not sure if it makes much of a difference.

I'm planning on taking apart the air handler to check out the inside in the morning. We cleaned the evaporator 1-2 years ago. Thanks for any advice.

 

[Fitter30]

Looks like a standard upflow furnace. Blower blowing air through the coil. Condensate drain doesn't need a trwp because drain is pressurized from the blower. From the age of the furnace the condensate pan might be rusted out. GFI tripped from water getting wires and connectors wet.

 

[Sponsor]

 

[liveanddiyinla]

Looks like a standard upflow furnace. Blower blowing air through the coil. Condensate drain doesn't need a trwp because drain is pressurized from the blower. From the age of the furnace the condensate pan might be rusted out. GFI tripped from water getting wires and connectors wet.

Thanks for replying! I took care of this in the morning and the A/C ran all day afterwards without issue. There was a lot of rust in the condensate pan, but it wasn't rusted through. The elbow trap was clogged.

Are modern air handlers easier to maintain? I found it pretty cramped in the evaporator, had to brush it out with a toothbrush since a small vacuum brush head wouldn't fit. I'm thinking of replacing the a/c with a heat pump eventually.


Here is what I did, hope it helps someone in the future.

Opened the air handler and removed the brace so that I could remove the cover from the evaporator. The brace must be removed to be able to remove the top screw from that triangle cover.

Cleaned out the evaporator with a toothbrush and and cleaner.

Attached a wet/dry vac to the end of the condensate drain line and created an airtight connection with a tube made out of a cut plastic bag taped to each end - this worked out perfectly.

Used an empty water bottle to run about 3 gallons of water through the evaporator coils and into the pan. I needed to seal the tee to create suction and used a plastic bag to free up my hands. Make sure to use a bag that won't get sucked through.

The drain is clean and clear. Took about 3 hours, since I wrestled with the evap cover for awhile before remembering about the brace. Plus, it's a bit of a messy job and needed some cleanup. Thank God it's done

 

[WorthFlorida]

Seeing rust at the bottom of drip pan is very common from the steel bracing. Your coils are aluminum which makes it maybe no older than 15 years old but the duct work is far older.
Condensate lines need to be checked every once in a while as you found out. But you don't have a SAFE T Switch. It gets wired into the 24v ac and when the water backs up the float switch opens the 24v's and it shuts down the system.

On my last house for twenty six years, the first floor condensate drained always clogged no matter what I did. As you did, I would use the shop vac to suck things out or with a garden hose shoot water into drain from the outside to back flush it. In my case it was always slime and mold.

There are two configurations. One threads in the drip pan and the other is a TEE which it looks like you would use. Not all SS1's come with the clean out tool but do get one. It allows to flush from the drip pan. It can be purchased separately. At most hardware stores pan tablets can be bought for maintenance. Drop one in the drip pan.

 

[Jadnashua]

It is fairly common for crud to grow in the condensate line, and sometimes in the drain pan, so you do need to clean them periodically. I had a woody fungus grow in mine on time that was a bear to get out. Luckily, it's in the basement, so the water damage didn't do anything.

It's normally not a good idea to have the circuit in the bathroom feeding other bits, but it's not bad that the GFCI tripped...all it takes is >0.005A of leaking current to trip it...enough to give you a good shock, if you were to touch it before it tripped. While water isn't a great conductor, lots of people get killed with electricity and wetness.

 

[WorthFlorida]

You said rest room, is this a commercial use area? Well it really doesn't matter but the drains are done with electrical PVC conduit. Nothing wrong with that. Electrical conduit has more UV protection for outdoor use.

The tee on the trap is on the wrong pipe. It should be one the down pipe so you can flush it out with a hose that makes it much easier. The trap is also not needed. When the pipe goes down and out, that be a 90* elbow, straight outside then a 90* elbow going up. Add About a 6 inch pipe then another elbow going horizontal. A few inches of pipe and use a 45* or another elbow. Essentially you are make the trap outside. This how it's done on most residential homes in Florida. If the trap plugs up, sometimes the water, as it rises up to the air handler, there be enough pressure from gravity to push out any crud.

Your install has been working for years without problem so there is nothing wrong with it. A slight change of the drain line could make thing cleaner if you ever replace the AC unit.

 

[liveanddiyinla]

Seeing rust at the bottom of drip pan is very common from the steel bracing.

Is the condensate drain pan ever made out aluminum? Seems that all the aluminum parts in this old system (coils, registers) are in in good condition while the rest... Not so much. Also, the pan sits flat instead of sloped down to the drain line port, which allows water to just sit in that steel pan.

Your coils are aluminum which makes it maybe no older than 15 years old but the duct work is far older.
Condensate lines need to be checked every once in a while as you found out. But you don't have a SAFE T Switch. It gets wired into the 24v ac and when the water backs up the float switch opens the 24v's and it shuts down the system

That's interesting about the age of the unit, one of my neighbors mentioned that it's probably original to the house, which was built in the mid 50s. What were the coils made out of before? That Safe-T-Switch looks like a good idea, I'll check it out. Is the clean out tool you mentioned made by Speed Clean?

 

[liveanddiyinla]

@jadnashua
Good point about the GFCI - that's why we put it in once we moved in. There wasn't one in the restroom before, just a standard outlet.

Don't know why the restroom, furnace blower fan, and another outlet are on the same circuit, but it's the original wiring.

 

[liveanddiyinla]

@WorthFlorida
Good catch on the electrical conduit and thanks for letting me know about the elbow. I suspected it was on the wrong side.

It does seem like the trap made with two elbows immediately after the drain pan would get clogged easily. Are you suggesting to remove that trap and make a long trap on the bottom run near the drain pipe exit?
Do you mind re-explaining how you run the drain line? It runs through the floor(single story house), into a crawl space, and outside to the yard through a mesh vent.

 

[WorthFlorida]

Units up to about the mid 2000 decade the coils were made of copper with steel framing, Drip pans were steel with sometimes a wax coating. Now the pans are plastic and coils and framing are aluminum. The most important is the efficiency went way up. Today's energy laws require Seer 14 for the compressor and with a matching air handler adds another 1 SEER. When I get time on my iMac I'll do a drawing and pictures for the condensate line.

 

[Jadnashua]

Many a/c units require a condensate trap. Making one up yourself can be tough to always keep clean. I have one similar to this. Mine came with a brush with a long, flexible handle so you can push it into and through to help clean things up. https://www.amazon.com/Rectorseal-8...s=condensate+drain+trap&qid=1597862808&sr=8-1

 

[WorthFlorida]

Here is a typical setup in Florida. A trap is always needed but having two of them will not drain well. The condensate and lines are run inside a 4" conduit to the outside. The picture is my house all done by AC contractors including when the unit was replaced in in 2014. Florida counties require a permit and inspection which was performed. If the condensate line goes horizontally straight out the wall or down to a floor drain and no traps at the end of the condensate line, a trap would be needed usually near the A coil. The last pic is a condensate trap typically used at the A coil.

Notice the Safe-T Switch is on a separate connection and it is moveable to to clear the access panel. The tee as you can see on the left with no trap. The second picture shows the top part is removed for cleaning access. BTW, last nigh I found the UV light to be burned out and time for a little round-up outside. The drain drips into a perforated 2" drain hose that is covered with a sock to allow the water to not puddle. Something you usually do not see.

 

[Fitter30]

Here is a typical setup in Florida. A trap is always needed but having two of them will not drain well. The condensate and lines are run inside a 4" conduit to the outside. The picture is my house all done by AC contractors including when the unit was replaced in in 2014. Florida counties require a permit and inspection which was performed. If the condensate line goes horizontally straight out the wall or down to a floor drain and no traps at the end of the condensate line, a trap would be needed usually near the A coil. The last pic is a condensate trap typically used at the A coil.

Notice the Safe-T Switch is on a separate connection and it is moveable to to clear the access panel. The tee as you can see on the left with no trap. The second picture shows the top part is removed for cleaning access. BTW, last nigh I found the UV light to be burned out and time for a little round-up outside. The drain drips into a perforated 2" drain hose that is covered with a sock to allow the water to not puddle. Something you usually do not see.

View attachment 65359 View attachment 65360 View attachment 65361 View attachment 65362

Electric furnace and air handlers need a trap because the evap coil is on the suction side of the blower negitive pressure. Gas furnaces most ave the evap coil on the positive side of the blower.