HVAC installer never connected the condensate pump's safety/overflow switch to the AC unit.

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gfw

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So, my understanding is that if the condensate pump fails and fills up, this switch should tell the AC to stop running. How critical is this? It seems like all that would happen is the pump reservoir would overflow, but it's possible that water could get into something important.

There is a controller for the AC near the pump - it's obviously the controller since it has wires to the thermostat and the ventilation timer. It's hard to see in there, but the back of that controller might have a couple of wires sticking out, not attached to anything. Is that likely where the condensate pump safety switch should be connected? Is there any way to be sure?
 
Stop trying to answer your own question!
Are you here for help, or for some other reason?

The overflow float sensor stops the AC from creating condensate that causes flooding and water damage.
 
> The overflow float sensor stops the AC from creating condensate that causes flooding and water damage.

Was it not clear that I already know this? The real question is

> Is that likely where the condensate pump safety switch should be connected? Is there any way to be sure?
 
Yes, connect the wires, turn on the AC, lift the overflow float all the way, the AC should turn off.
 
To which wires on the controller (there are three unconnected ones, blue, red, black) do I attach the white leads from the pump?SAM_3839.JPG
Or do I connect the white leads to somewhere else? This is the information I'm missing, since the original installer didn't bother to do it.


(edit) - Ah, I think you're suggesting that I just try the wires by manually testing the switch. If I have the right wires, the AC will shut off. Agreed. But is there any danger of me damaging anything by guessing wrong?
 
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Yes, you could potentially damage something if your not sure what your doing and just start hooking up wires at random.
I would want to see a wiring diagram for the furnace and the condensate pump before providing any advice.
Most likely we're just going to interrupt the control power to the entire unit to shut it down.
 
Call whoever installed the condensate pump and controller, have them hook it up.

Or look for brand and model number on that controller, there is likely a wiring diagram online.

I think you said the controller is already wired into the furnace controls, right?
 
Yeah, I emailed the installer on Monday. Trouble is, they installed it 12 years ago and probably don't want to admit they screwed this up. I've just emailed again.
I'm lucky that the pump lasted this long and then failed at a point in time when I would notice before it became a problem.
I don't see a brand & model on the controller, but maybe I can find some info in the paperwork from 12 years ago.
 
I think you never stated that your condensate pump had failed.

You just said “if the condensate pump fails and fills up”.
 
Ok, so if your going to replace it, follow the new pump installation instructions, it will tell you where to land the wires from the pump onto the unit.
 
GFW ... whether or not to use the overflow protection device in the pump ... depends on where the pump is.
My experience is to not use the device (leave the wires disconnected) if the pump is in a place where some water getting onto the floor, won't cause any damage (a basement near a floor drain or sump pump pit).
The main reason for this is .. if the overflow device is hooked up and in use, it will stop the AC unit when there is an overflow. Then, you will probably call the AC repairman and incur at least a $100 service call charge, plus any work they need to do.
So ... I'd say only use the overflow device if the overflow will actually causes some damage.
best regards
 
Just because it’s not connected didn’t mean they “screwed up”. It takes time and materials to connect that safety, the safety is an optional device. If it’s not in your contract to have one then they may have just bought the pump that has that safety switch included because the pump without it was not in stock. If in the contract they say it will have one installed THEN you can say they screwed up, but don’t throw them under a bus just because you see wires that are not connected. They already did you a favour by spending more money on the pump with the switch so you could have the system up and working sooner.

Is the controller on the floor a moisture detector wired to turn the unit off in the event of a leak?

Blindly connecting wires is an expensive way to learn how to install an accessory. You can do a lot of damage that way.
 
GFW ... whether or not to use the overflow protection device in the pump ... depends on where the pump is.
My experience is to not use the device (leave the wires disconnected) if the pump is in a place where some water getting onto the floor, won't cause any damage (a basement near a floor drain or sump pump pit).
The main reason for this is .. if the overflow device is hooked up and in use, it will stop the AC unit when there is an overflow. Then, you will probably call the AC repairman and incur at least a $100 service call charge, plus any work they need to do.
So ... I'd say only use the overflow device if the overflow will actually causes some damage.
best regards
That makes a lot of sense, thanks. In this case overflow would do *little* damage, but could get into the MERV-16 filter (whose box it's sitting on). After that, it's just the concrete floor of the garage. Water getting into that filter box ... eh, probably wouldn't corrode anything. I'm now inclined to leave it as it was installed. Thanks for the insight!
 
One way to minimize overflows is to clean out the discharge hose.

They are usually just soft skinny clear vinyl hoses.

Debris and slime tends to build up in the low spots where they sag, and the hose can also get pinched where it is zip tied or duct taped to supports.

Sometimes they get so pinched or stiff they need replacement.

Taking the hose off of the pump box and blowing it clean with an air compressor at least once a year is a good idea.

I also have one client that had frequent backups, due to a crazy long discharge line of almost 90 feet, with lots of droops.

After blowing it out, it happened again and I found slime building up in the droopy sections.
Now I pour about a quart of about 10 percent bleach solution into the pump box once a month, and let it pump through the line.

No more backups for several years since doing that.
 
Yes, the original hanging of the drain line had lots of sags. I've mostly fixed that by adding a lot more supports. There's still a couple of spots that have a sort of twist-kink, but it's not blocked. In fact, the line itself is remarkably clean. I may replace the drain line eventually because of the kinks, but it's all working fine right now.
How this story got started was that the pump got clogged by slime right in the reservoir. I'm going to empty and clean the reservoir once a year after the end of cooling season starting this year. The guys who installed this never told me anything about maintenance. I clean the (outside) heat exchange vanes once a year just after cottonwood season, but I only started doing that 3 or 4 years after install when there was a problem.
 
The pump also runs during heating season.

Burning natural gas makes water, and a humidifier makes drain water.
 
Good points, however there are things I didn't mention.
1. I live in the PNW and have no humidifier (no need!)
2. The gas heat only runs in the coldest part of winter because the "AC" is really a heat pump. So with the climate here there's a significant shoulder season where we don't run it in either heating or cooling mode, then for most of heating season it's still not burning natural gas. So if I'm going to pick one point to do a yearly cleaning of the reservoir, it may as well be in the fall shoulder season.
 
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