Fifth Avenue Forum

Why would my outside AC unit cause my inside furnace to leak? I legit don't understand this stuff, not being a smartass.

Big PVC pipes run through it but I couldn't tell you why.

Furnace is leaking water, first problem it has had since we moved here three years ago and this is our last month living here. Yay.

I had that issue, ended up being a blockage in the pipe.

Yeah, that's what I think too. I took it apart as far as I was comfortable but couldn't get to the source.

You don't see where it's leaking from? I had to deal with an AC leak last year. For starters, the drain clogged so I bought this:


My BIL wired it up since he's an HVAC guy, but it's nice being able to see any blockages at the elbow, and if it gets clogged, the system is shut down to prevent leaks. I also needed to replace the a-coil/condensate pan, which has some cracks in it. It was about $90 in parts, but that was at cost, and labor was paid in beer.

Speaking of soil, we decide to dig a patio/fire pit into the hillside in our back yard. It's not really feasible to get an excavator in there, so I've gotten underway manually. It has really just become an exercise routine more than anything else. I think it will take weeks to finish. 15'x15' and probably about 30-36" at the highest/deepest point. I figure around 12 yards in total to be dug out.

Excavation continued this weekend, and I encountered this behemoth. Still not loose at all.



Any ideas on how to remove? Think a sledge can break it up?

oh man. I don't know about a sledge breaking that up. I've never done it, but a neighbor told me he has this issue and he drilled a hole with a mason drill then hammered rebar into the hole and it eventually split. No idea if that'll work here though

oh man. I don't know about a sledge breaking that up. I've never done it, but a neighbor told me he has this issue and he drilled a hole with a mason drill then hammered rebar into the hole and it eventually split. No idea if that'll work here though

That's an interesting idea. It's a shame it's not a bit lower down. I'd leave it as a seat for the fire ring, as the location more or less works out, but I think it'd be too high for the finished product.

Holy ****. A portion of our backyard used to be an old city alley, so we have a ton of large stone bricks that make digging a pain in the ass. I can't imagine your thought process when you hit that monster.

Dynamite

Keep digging farther down and bury it?

Might be a boss rock down below

I saw this product used on This Old House once, and it seemed to work very nicely:

I imagine that you may still need to rent a jackhammer from HD to finish off the bottom, though.

I’m not sure an electric jackhammer will even crack that. I think that’s gonna be your best bet though. A jackhammer running on compressed air would be better....but who the hell has that

Why would my outside AC unit cause my inside furnace to leak? I legit don't understand this stuff, not being a smartass.

Big PVC pipes run through it but I couldn't tell you why.

The outside unit cools the freon but there's a coil inside that the cold air runs through. if that gets dirty it freezes up with condensation. Then the outside unit kicks off because it senses the coil is froze up, and when the inside coil melts, it leaks out of the air handler.

At least that's how mine is.

Cool, thanks. That makes sense.

I'm going to grab a new filter tonight and see what happens. It didn't run at all overnight so I assume it would've thawed. It's a massive filter, 25x20x4" or so. It doesn't look particularly bad but who knows, worth a shot.

I think in the scenario i have outlined, your outside unit would've tripped itself off. So it'd be pretty warm in the house today.

I need the new filter anyway so I'm going to give it a go. Nothing to lose, just have to wring out the towel that is catching the water every so often.

Where is the water leaking from?

I took it apart as far as I was comfortable but couldn't get to the source.

Somewhere in the middle, I dunno.

I took it apart as far as I was comfortable but couldn't get to the source.

Somewhere in the middle, I dunno.

So it's dripping down from the coil onto the blower, etc. inside the furnace? If so, you can open the rear panel to check the A-coil and pan, which will also give you a good look at the drain. If there's standing water in the pan, it's clogged. If not, you could very well have a crack in the pan or worse. If you keep the system off and let it all dry, you could pour water onto the pan slowly to see if starts leaking again.

As much as I took apart I could not see a drain. I took the exterior panels off, as well as the panel that says you'll die if you take it off (while standing in a puddle of water) and still couldn't find the source. At that point I put it back together and complained on the internet.

As best I can see it's coming from the area of the Condensing Heat Exchanger. It's slowly seeping out from behind a panel, onto a horizontal surface where it trickles down past the fan and onto the floor.

Not trying to insult your intelligence - you're sure this is not normal draining of water, right?

Well, in three years it's never come out of the front of the unit, no. And there is no path to the drain in the utility room from where it is.

It's against a wall so I don't see how it drains. I imagine that there is a plugged hole, though.

Insult away, I don't get this stuff at all. I could replace the entire HVAC system in a BMW but this big brown box is just full of riddles for me.

Not sure if the picture works. Water seems to be seeping from that recessed panel behind the downpipe with the red collar on it. Water runs across that shelf and through a machined hole and falls down between the blower fan and air filter (on the right). When it collects enough it spills out onto the floor and into the towel.

There is a hose that runs from the drain in the floor, around the room, behind the furnace, and into that box hanging on the left hand side. That white outlet pipe on the left goes into that box on one end, and behind that panel on the inside.

That panel looks like murder to take off. Would have to remove a **** ton of stuff.