GFCI tripping and cutting off furnace

Tim

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This has been happening 1-2x/month for quite a while, now it’s more like 1-2x/day.

This little pump is plugged into the outlet where the GFCI breaker is located. When the GFCI trips, the whole HVAC system shuts down.

How confident should I be that replacing the
pump would solve my problem? Or is it
Likely that “something else” is tripping it?

I’m 99% certain that the HVAC unit itself is on its own circuit and the pump is wired into a switch on the HVAC, so that if the pump fails the furnace shuts off.

Electricity has freaked me out ever since that time I peed on a fence at grandpa’s farm.

DAC7FCAF-2DBF-4CC8-BAF9-A5E0240E000B.jpeg DE20511C-7016-42C0-939D-AE93068BF8A5.jpeg
 
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My first inclination would be to run an extension cord to power the pump from an outlet on a different circuit and see what that does. Also, breakers do wear out. If you’re lucky enough that it’s one carried by Home Depot, they’re not prohibitively expensive.
 
My first inclination would be to run an extension cord to power the pump from an outlet on a different circuit

See....this is why I come here. Thanks for my early dose “why didn’t you think of that, dumbass?”
 
See....this is why I come here. Thanks for my early dose “why didn’t you think of that, dumbass?”
I come here hoping someone will teach me how to shoot. :(
 
Ok...so ran a drop cord. When I unplugged the pump, the furnace kept running.

I suspect the furnace only cuts off when the water level in the pump gets a certain level and the float closes a circuit - the red cord in my pic above.
 
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Have you got another identical GFCI breaker? You could swap them temporarily.
 
I’m looking more closely at the photo. Are we talking about a GFCI outlet or circuit breaker?
 
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I looking more closely at the photo. Are we talking about a GFCI outlet or circuit breaker?

outlet. The one in the pic above where the pump is plugged in.
 
Ok...so ran a drop cord. When I unplugged the pump, the furnace kept running.

I suspect the furnace only cuts off when the water level in the pump gets a certain level and the float closes a circuit - the red cord in my pic above.
If done properly, this is correct. One of the switches in the pump should cut the HVAC if the level gets too high due to pump not working or plumbing malfunction. This is to keep the furnace from overflowing the reservoir into the pan. Depending on the age of the unit, there could also be a switch mounted in the pan that will shut the system down. Your pump could be the issue. It could also be the GFCI is faulty. Try another outlet for the pump. If it uses GFCI and doesn't trip, it's the GFCI.

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outlet. The one in the pic above where the pump is plugged in.

Is the circuit your running drop cord to got a gfci? If so the original one is probably bad and needs replacement. If it still trips on the drop cord that’s into another gfci the pump is going bad. The pump is wired to a switch that tells it when to pump out the condensation from that pan. If the hvac doesn’t sense it’s operationally ready it shuts whole system down.

@Jeppo I’ve been trying to teach you to shoot lol [emoji23]


Sent from my iPhone using Tapatalk
 
The furnace should not be on a GFCI outlet.
Replace the GFCI outlet shown with a regular outlet
 
This has been happening 1-2x/month for quite a while, now it’s more like 1-2x/day.

This little pump is plugged into the outlet where the GFCI breaker is located. When the GFCI trips, the whole HVAC system shuts down.

How confident should I be that replacing the
pump would solve my problem? Or is it
Likely that “something else” is tripping it?

I’m 99% certain that the HVAC unit itself is on its own circuit and the pump is wired into a switch on the HVAC, so that if the pump fails the furnace shuts off.

Electricity has freaked me out ever since that time I peed on a fence at grandpa’s farm.

View attachment 179927 View attachment 179928

My first inclination would be to run an extension cord to power the pump from an outlet on a different circuit and see what that does. Also, breakers do wear out. If you’re lucky enough that it’s one carried by Home Depot, they’re not prohibitively expensive.

They also get worse the more they are tripped. Some of them now have a constant self test and will tell you when they have gone past their usefulness. I have waterfall pump that trips the GFCI and I know it is the outlet or the run because I can take the pump and plug it into another outlet with a GFCI and it will work fine. My issue is temp related. Super hot or super cold and it trips. You can also get a plugh which will tell you if it is wired correctly, going to ground etc....
 
The furnace should not be on a GFCI outlet.
Replace the GFCI outlet shown with a regular outlet


The FURNACE is on its own circuit.

The CONDENSATE PUMP is in a GFCI circuit.

The entire HVAC unit was replaced 6-7 years ago.
 
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The FURNACE is on its own circuit.

The CONDENSATE PUMP is in a GFCI circuit.

The entire unit was replaced 6-7 years ago.

It is my understanding that the pump has to be on a GFCI because water is involved.
 
That GFCI outlet is $13 at Home Depot. I’d invest the $13 and 5 minutes as my next troubleshooting step. ;)
 
It’s never tripped right away, so I’m going to let it run off the drop cord for a full day to see if it trips. If it doesn’t, I’ll replace the outlet.

If it does trip, I’ll replace the pump.
 
Might you have a GFCI outlet that is also on a GFCI circuit breaker? That can cause all kinds of wonky trips.

True. On top of that check if that outlet feeds other outlets. There could be another plug in device that just adds up to the trip threshold on that GFCI circuit run.
 
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my question is if the drain in the pan is not clogged why do you need the pump

the furnace sits below grade, so the condensation has to be pumped UP and out.
 
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I've a sump pump that trips the GFI every time it's finished pumping the water out. You can test it by dumping some water into the pan and watch when the pump turns off.
 
@Jeppo I’ve been trying to teach you to shoot lol [emoji23]
Sent from my iPhone using Tapatalk[/QUOTE]

Me too Zack but I'm beginning to think there's no hope for him.:p
 
GFCI outlets suck... A good portion of them are crap new out of the box. Any wear on a motor looks like ground fault to the GFCI. The whole concept is stupid and the NEC knows it.
 
that GFI is high enough up the wall if water ever gets that high you have much bigger problems … go to lowes or HD and get a plain receptacle and cove cost $1.50 plug a light source into the GFI and find the breaker . you will know you have the correct breaker when the light goes off. replace GFI with new receptacle and never have trouble again you are correct about the float once enough water gets in pump it breaks low voltage circuit to furnace
 
that GFI is high enough up the wall if water ever gets that high you have much bigger problems … go to lowes or HD and get a plain receptacle and cove cost $1.50 plug a light source into the GFI and find the breaker . you will know you have the correct breaker when the light goes off. replace GFI with new receptacle and never have trouble again you are correct about the float once enough water gets in pump it breaks low voltage circuit to furnace


Seriously!!! o_O:eek::oops::rolleyes:
 
that GFI is high enough up the wall if water ever gets that high you have much bigger problems … go to lowes or HD and get a plain receptacle and cove cost $1.50 plug a light source into the GFI and find the breaker . you will know you have the correct breaker when the light goes off. replace GFI with new receptacle and never have trouble again you are correct about their broken, correct? float once enough water gets in pump it breaks low voltage circuit to furnace
The thermostat will not operate when the low voltage circuit is interrupted, correct?
 
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I may be getting a reputation for asking the dumb question, but why is your HVAC producing condensate at this time of year? Seems unreasonable given your location.
 
I may be getting a reputation for asking the dumb question, but why is your HVAC producing condensate at this time of year? Seems unreasonable given your location.

All high efficiency units generate condensate on the heat cycle. I think it's the same as when water comes out of the tailpipe of a car when it first starts up.

And yes, you are the best I know with those questions. ;)
 
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I may be getting a reputation for asking the dumb question, but why is your HVAC producing condensate at this time of year? Seems unreasonable given your location.


Hmmmm
 
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