# Swamp cooler pops GFCI



## broken68 (Sep 2, 2010)

I'm running into a problem with my swamp cooler. For some reason it has been working fine up until this summer. For some reason it is popping the GFCI as soon as you turn it on high, though it wasn't before. I've verfied that none of the connections have gotten wet, became loose or corroded from the moisture. I put my 3 prong tester on the circuit and it says everything is correct, no open grounds etc. Only does it on high cool or high vent, everything else seems fine. Only thing that has changed since last year is the new smart meter, and I put a new cooler motor on (same brand and hp as I pulled off of it). It was doing this with the old motor, so I had assumed the motor was failing, but same problem with the new one Again has been working fine for the last 4-5 years and just recently started flaking out. I've tested the rest of the circuit and nothing of high amperage or anything else that's running on that circuit other than the cooler. There's more receptacles, but nothing plugged into them. The motor states it pulls 10.8/4.6 amps (10.8 at startup). It's on a 20 amp breaker, and I think a 15 amp gfci. Any thoughts on what to do next I am at a loss?


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## gregzoll (Dec 25, 2006)

It is telling you that the Swamp Cooler motor has a problem. Usually Swamp Coolers do not get plugged into GCFI protected circuits.


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## fabrk8r (Feb 12, 2010)

Have you tried a new breaker?


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## broken68 (Sep 2, 2010)

Cooler motor is new though? Been on less than 3 months. Kinda hard to wire those up wrong imo but I suppose I could have got a faulty one even though it is new. I assumed since it was doing what the old one was doing its not motor related. I haven't tried a new breaker, but I have tried a different gfci. I was told that anything that is hooked up around water needs a gfci. I know kitchens and bathrooms, but was told swamp coolers too. Should I eliminate the gfci? Like I said it has been working fine for the last 4-5 years like this, just started since they hooked up the smart meter. I've read where the smart meter can put out high frequencies that can trip older gfci's which didn't have shielding that the new ones have, which is why I traded out the gfci thinking that might be it. Maybe I'll try trading breakers and see what that does. Any other thoughts, throw my way please. I've went over everything I know to do. I consider myself to be a decent diyer when it comes to home improvement, but this one has me stumped.


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## a7ecorsair (Jun 1, 2010)

gregzoll said:


> It is telling you that the Swamp Cooler motor has a problem. Usually Swamp Coolers do not get plugged into GCFI protected circuits.


How can you draw this conclusion? A tripping GFCI is only indicating that there is a difference in current between hot and grounded (neutral) conductor. 
OP, you mentioned that there are other outlets on this circuit. Were in the string is the GFCI outlet or is it a GFCI breaker?
As mentioned, a tripping GFCI is telling you there is a difference in current between the hot and grounded. I'm assuming this is a GFCI outlet so the easiest thing to try is to remove the wires connected to the load terminal of the GFCI if possible unless the cooler is one of these. Let us know how this circuit is set up.


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## broken68 (Sep 2, 2010)

The power is running from a gfci outlet to a rotary style cooler switch to cooler. Best I remember it's last on the chain, though it's been a while. The outlet itself was popping it's built in breaker. I was told to do it this way so that if motor or water pump on cooler happened to seize up (water pump especially) the difference in voltage or load would pop the gfci and not sit there getting hot and cause a fire. I just changed out the breaker for another. Will keep everyone posted if this fixed the problem or not, but so far so good. Weird that it was only popping on high though.


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## broken68 (Sep 2, 2010)

Ok as stated, I changed out the breaker. Now it runs on high for about 5 mins before popping the gfci, before switching the breaker it was instantly as soon as it was on high cool or high vent. I also pulled the switch cover to make sure connections were tight at the switch. Runs day and night on low vent or low cool with no problems.


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## gregzoll (Dec 25, 2006)

Only way that it would cause a fire, is if the pump seized, the motor seized, or an electrical short happened. Since you only have three parts, two being motors, that leaves the rheostat, which may not be the culprit, but only way is to have a good electrician that can do a leak test on the Swamp Cooler to find out.


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## a7ecorsair (Jun 1, 2010)

I haven't been around swam coolers since I live in Calif. in the '70s but I know they are not very complex. What is a *smart meter* and who hooked it up?


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## fabrk8r (Feb 12, 2010)

I'd be willing to bet that the motor has a bad winding. 

What happens if you leave it on high until it trips the breaker and you don't reset until the motor cools off?


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## broken68 (Sep 2, 2010)

PG&E upgraded all their old meters to a new digital meter i.e "the smart meter". It replaced the old mechanical style meters with a new digital display meter that was "supposed" to save us money. My guess was to make them tamper proof from people running a magnet on each side of meter to slow down the wheel. Many people have noticed now their bills have almost doubled since the it's introduction. Ironically I'm in California lol. PG&E did the install back in the winter time so I didn't notice the difference until this summer when it was time for the cooler. I suppose it could be a faulty switch throwing a slightly different load signal, but the switch was replaced when I did the gfci setup originally about 4-5 years ago. As stated has worked all this time with no problems until this summer. It has me banging my head againist the wall. Not saying the smart meter is the culprit, but has been the only changed in the formula from 4-5 years ago that and a new motor this year, but again same brand motor, same hp, amps etc as the old one.


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## broken68 (Sep 2, 2010)

fabrk8r said:


> I'd be willing to bet that the motor has a bad winding.
> 
> What happens if you leave it on high until it trips the breaker and you don't reset until the motor cools off?


I can reset the outlet right after it pops and it will run about 5 mins each time.


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## fabrk8r (Feb 12, 2010)

fabrk8r said:


> don't reset until the motor cools off


Did the motor *cool* before you reset?


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## broken68 (Sep 2, 2010)

I've not tried that yet, I might try it this evening when the weather cools off a bit, but right now it's too hot not to have something. Low cool better than no cool


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## a7ecorsair (Jun 1, 2010)

fabrk8r said:


> I'd be willing to bet that the motor has a bad winding.
> 
> What happens if you leave it on high until it trips the breaker and you don't reset until the motor cools off?


If I've been reading this correctly it is the GFIC that is tripping, not a breaker. A GFIC trips if the current flow detected in the grounded conductor (white or neutral) is different than the current flow detected hot conductor (black). A breaker trips when the circuit current exceeds the breaker rating.
The GFIC would not be affected by a meter change.
OP, you said this is last in the string. This doesn't matter where in the sting the GFIC is placed but what would matter is if there is a pair of wires connected to the *Load* side of the GFIC. And BTW, the power to the GFIC must be connected to the *Line* terminals. Are there any other wires in the receptacle box where the GFIC is mounted? Is there anything connected to the *Load* terminals?


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## broken68 (Sep 2, 2010)

a7ecorsair said:


> If I've been reading this correctly it is the GFIC that is tripping, not a breaker. A GFIC trips if the current flow detected in the grounded conductor (white or neutral) is different than the current flow detected hot conductor (black). A breaker trips when the circuit current exceeds the breaker rating.
> The GFIC would not be affected by a meter change.
> OP, you said this is last in the string. This doesn't matter where in the sting the GFIC is placed but what would matter is if there is a pair of wires connected to the *Load* side of the GFIC. And BTW, the power to the GFIC must be connected to the *Line* terminals. Are there any other wires in the receptacle box where the GFIC is mounted? Is there anything connected to the *Load* terminals?


 Correct, the gfci is popping, not the breaker itself. Pulled the gfci and it's just the standard 1 black in 1 black out, one white in one white out with a ground at bottom of the outlet. Black is on gold screw white on silver as normal. Nothing else in the box. Looking straight at the outlet (plug ins facing you) you have:

w.....b

w.....b

Ground


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## Stubbie (Jan 7, 2007)

A swamp cooler also has a pump and float switch. I'd get in the wiring compartment and start isolating components by disconnecting the hots and neutrals and see if it only trips the breaker when these components are connected with the motor.

A simple diagram may look something like this....


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## broken68 (Sep 2, 2010)

There is no electrical float switch on this cooler. It uses a standard brass float that shuts off the water when it reaches full. The switch itself (often called trailer switches) since they were found in mobile homes mostly. It has pump only, high vent, low vent, high cool, low cool and off. Gfci only pops on high cool/high vent nothing else. And it's wired exactly like your diagram


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## Stubbie (Jan 7, 2007)

It has a blower motor and pump motor ... no?


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## a7ecorsair (Jun 1, 2010)

broken68 said:


> Correct, the gfci is popping, not the breaker itself. Pulled the gfci and it's just the standard 1 black in 1 black out, one white in one white out with a ground at bottom of the outlet. Black is on gold screw white on silver as normal. Nothing else in the box. Looking straight at the outlet (plug ins facing you) you have:
> 
> w.....b
> 
> ...


GFCI are not "Standard" You have other outlets that are _*protected*_ by this GFCI. Look at the back of the GFCI and you will see Line and Load.
Was the GFCI installed mainly because of the cooler or were you expecting to protect other outlets?
If the GFCI was installed to prevent shock while working on the cooler, then you should wire nut the two blacks and add a pig tail to the line gold terminal and do the same with the white neutrals, and the bare grounds.
Leave the load terminals empty and turn in the screws.
This will place only the cooler on the GFCI and allow you to verify that the problem is in the cooler.


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## broken68 (Sep 2, 2010)

It was installed should the motor on the cooler or the motor on the pump seize(water pump more likely), then it wouldn't sit there being seized up and getting to the point of causing a fire. The seized motor would produce enough load to pop the gfci, thus killing power to it in case no one was home at the time. That was the only reason it was installed.


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## a7ecorsair (Jun 1, 2010)

broken68 said:


> It was installed should the motor on the cooler or the motor on the pump seize(water pump more likely), then it wouldn't sit there being seized up and getting to the point of causing a fire. The seized motor would produce enough load to pop the gfci, thus killing power to it in case no one was home at the time. That was the only reason it was installed.


You don't understand the purpose nor the operation of a GFCI. Let's see what Stubbie adds.


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## broken68 (Sep 2, 2010)

a7ecorsair said:


> GFCI are not "Standard" You have other outlets that are _*protected*_ by this GFCI. Look at the back of the GFCI and you will see Line and Load.
> Was the GFCI installed mainly because of the cooler or were you expecting to protect other outlets?
> If the GFCI was installed to prevent shock while working on the cooler, then you should wire nut the two blacks and add a pig tail to the line gold terminal and do the same with the white neutrals, and the bare grounds.
> Leave the load terminals empty and turn in the screws.
> This will place only the cooler on the GFCI and allow you to verify that the problem is in the cooler.


So basically I would hook it up this way to isolate the circuit to the cooler only, so if it pops after that then I know it's cooler? Just to make sure we are on the same page.


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## a7ecorsair (Jun 1, 2010)

broken68 said:


> So basically I would hook it up this way to isolate the circuit to the cooler only, so if it pops after that then I know it's cooler? Just to make sure we are on the same page.


Yes, that is my point. As it is connected, you have something else in the house that is being protected by this GFCI.


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## gregzoll (Dec 25, 2006)

If the motor or pump seizes, it will pop the breaker because it is creating a shorted condition, not a voltage drain to ground, which would trip the GCFI.


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## Stubbie (Jan 7, 2007)

gregzoll said:


> If the motor or pump seizes, it will pop the breaker because it is creating a shorted condition, not a voltage drain to ground, which would trip the GCFI.


What is a voltage drain to ground??


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## Stubbie (Jan 7, 2007)

If the gfci is protecting downstream and it never trips until you operate the cooler then the cooler is suspect. You could disconnect the cable going to other protected outlets if you want to be sure.

As long as the incoming power is connected to the line terminals anything plugged into the gfci is protected. 

You are however not understanding how a gfci works and your reason for using it is not correct and will not trip the gfci , it might trip but not because of the overload from a seized pump. 

GFCI's do not need the ground to function properly, what they do is what a7ecorsair is saying... they measure/monitor the current flowing in the hot wire and the neutral when operating an appliance. This current will be equal in both wires under normal conditions. If there is 5 amps in the hot and *not *5 amps also in the neutral then the gfci trips out because it is 'seeing' that current is going somewhere it should not be. 

They detect current leakages at around 5ma if that occurs the gfci trips.
​Anyway you need to make sure all your connections in the cooler wiring compartment are clear of any metal especially the neutral connection. Be sure that there is no moisture building up or dripping on the connections etc.. Be sure that the ground wire is not touching neutral that sort of thing.


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## frenchelectrican (Apr 12, 2006)

Also along the Stubbie's comment I do not know if you have clamp on ampmeter if so you may want to check the motor current drawage on both low and high speed I know you mention nameplate but double check it on both low and high speed and to see if over the limit espcally on high speed.

Some case the bearing on the motour can go bad also that can cause the breaker to trip in few minutes. 

The other test you can try is unplug the pump motour and see what happend if not tripping on high speed then you may have issue with pump motor if not then just unplug the fan motour and run the pump alone and check the current drawage on that as well.

Merci.
Marc


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## broken68 (Sep 2, 2010)

I'd like to thank everyone for their help trying to solve this problem. I went back and talked with the person that originally told me to put the gfci in. He was basically saying the same thing as you guys, that the gfci is only going to protect it from where it was put in down the line. I misunderstood why he had me put the gfci on, I thought it was for what I described earlier, but I was wrong, it was in case moisture got in the line I guess, to be honest still a bit confused by what he was saying and he didn't have time to explain it further. I admit wiring is something I don't know much about other than your basic receptacles and switches, after that I get a bit lost. I'm going to double check everything again tomorrow as I ran out of daylight today. Maybe I will eliminate the gfci altogether and see if it pops the breaker on high. If the gfci is not beneficial to me, I don't see the purpose of having it on there tbh. Perhaps the circuit is producing just over the 15 amp mark enough to pop it. Not sure how, but worth a try I guess.


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## broken68 (Sep 2, 2010)

frenchelectrican said:


> Also along the Stubbie's comment I do not know if you have clamp on ampmeter if so you may want to check the motor current drawage on both low and high speed


I don't have the clamp on style ampmeter just a regular multimeter with the 2 probes. This is what I wanted to do originally, but at the time it wouldn't stay on long enough to get a reading. Before I changed the breaker, it was instantly popping it as soon as it hit high, now that I changed the breaker (not gfci), it can run about 5 minutes before it pops. At least it's running long enough now to get a reading. So that's something else to check tomorrow. Thanks again for the help everyone.


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## frenchelectrican (Apr 12, 2006)

If you going to read the amps on the motor load as I say before use the clamp on that is the safest one you can use and do not use the multimeter for reading current more than just a amp or two the most otherwise it can wreck it.

The motor starting current will wreck the mulitmeter pretty fast.

The clamp on ampmeter I am not sure what they cost but IIRC it will be about 50 to 80 Euros {Dollars } unless you ask someone whom have one then they can loan ya one { throw in a case of beer or soda useally do the trick }

Merci.
Marc


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## broken68 (Sep 2, 2010)

frenchelectrican said:


> If you going to read the amps on the motor load as I say before use the clamp on that is the safest one you can use and do not use the multimeter for reading current more than just a amp or two the most otherwise it can wreck it.
> 
> The motor starting current will wreck the mulitmeter pretty fast.
> 
> ...


Ok thanks for that. I'll ask around and see. Maybe the tool rental place here in town has one if all else fails.


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## gregzoll (Dec 25, 2006)

I meant current drain, but most people understand the term voltage better, because they do not realize that other factors are in play to get their lights lit, etc.


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## Stubbie (Jan 7, 2007)

Broken68

You mention that sometimes it takes 5 minutes for the gfci to trip...? If you have a fault to ground or neutral or hot the trip is usually immediate. A winding insulation short/leakage I think would be immediate not in 5 minutes or so.... are you sure there isn't moisture dripping or forming on an electrical connection after it operates for awhile? the fact it only trips on HI should narrow down to pump or motor or moisture. The motor has a high speed winding or it may be the pump that starts automatically when high is selected ...not sure. The fact that it trips the gfci indicates a safety issue as current is going somewhere it shouldn't. Motors for these things are required to not have so much leakage that they trip a gfci unless they are faulty like a bad winding or something. IMO operating it on gfci is not a bad idea.


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## Stubbie (Jan 7, 2007)

gregzoll said:


> I meant current drain, but most people understand the term voltage better, because they do not realize that other factors are in play to get their lights lit, etc.


No problem Greg just wasn't sure where you were going with the term voltage.


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## broken68 (Sep 2, 2010)

Stubbie said:


> Broken68
> 
> You mention that sometimes it takes 5 minutes for the gfci to trip...? If you have a fault to ground or neutral or hot the trip is usually immediate. A winding insulation short/leakage I think would be immediate not in 5 minutes or so.... are you sure there isn't moisture dripping or forming on an electrical connection after it operates for awhile? the fact it only trips on HI should narrow down to pump or motor or moisture. The motor has a high speed winding or it may be the pump that starts automatically when high is selected ...not sure. The fact that it trips the gfci indicates a safety issue as current is going somewhere it shouldn't. Motors for these things are required to not have so much leakage that they trip a gfci unless they are faulty like a bad winding or something. IMO operating it on gfci is not a bad idea.


Well it started off being instantly once the cooler was switched to high cool or high vent. I changed out the breaker at the box and now it runs roughly 5 mins before it pops the gfci. I'm still looking for a clamp on style ammeter. but I've got the word out.


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## gregzoll (Dec 25, 2006)

They should have them at Lowes or Home Depot in the Electrical section with the tools.


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## broken68 (Sep 2, 2010)

gregzoll said:


> They should have them at Lowes or Home Depot in the Electrical section with the tools.


yeah just trying to find one local. Our nearest Lowe's and Home Depot is an hour drive away one way.


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## josh86442 (Sep 29, 2010)

*Figured it out!*

Well I have had the exact same problem with my unit I just put together. I got a old swamp cooler from my father in law and totally gutted it out and put new everything into the box. I have a 1 hp motor running the unit. After getting everything set up and running high cool would work fine for me but as soon as I switched it to low cool it would trip my gfi in garage! The strange thing is that sometimes it would do it right away and other times it would take 30 min. or so. I checked the amps my cooler was running and that part seemed fine. I went ahead and took out my gfi unit in garage I have heard that they do go bad sometimes if they trip a lot. I bought a 20 amp up stream and a 20 amp down stream gfi installed it and have had no problem since! The 15 amp down stream was the issue I beleive.


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