GFCI Hot Tub Plug problem

I own a 110 volt 20 amp Hot Tub it has a 15 amp GFCI plug I also have dedicated one circuit one outlet for just hot tub. first three months no problem then one day no power to the hot tub the GFCI plug tripped so I reset plug turned on hot tub and pop it tripped again. I call hot tub service line they said it was the pump motor so they sent me new pump . The pump install easy the electrical was one plug into the control board color coded. Filled tub plugged it in tried to turn tub on and pop I am like what the hell so for giggles I wired direct plug no GFCI into hot tub plugged it in and pumped started rite up. So I get a new GFCI plug they have same one at Home depot go figure anyways wire it up plug it in and POP . So I call service center they are sending me new GFCI apparently a 20 amp GFCI . I am thinking this is not the problem since it ran for two months with out issue. Some one suggested I have a double ground I have no idea what that is or how to troubleshoot that any head would be great to have thanks.
Jim

 

It would have been much easier to test by unplugging the pump and see if the GFI still tripped rather then replacing the motor.

Your problem is a direct short from neutral (white) to ground or possibly a water leak causing a partial short from hot to ground.

On on a hot tub.... the first thing I check is the heater element for a short to ground. That is a more common problem than a shorted motor.

You'll need a meter to diagnose your problem. Let me know if you have one.

 

Are you certain it is the GFCI tripping and not a high limit temperature switch or breaker inside the spa?

It is possible that it's the GFCI. They do make special cord end, 20amp ones for spas. I would try that before expending too much effort on other things. Also, is the GFCI on the end of your spa's power cord the only GFCI or is the spa hooked to a circuit protected by a GFCI circuit breaker or outlet?

 

Ok first it is on one circuit nothing else and no other GFCI breakers or outlets. Also the hot tub runs with plug directly into circuit no GFI hooked up Works perfect heats up and everything .I also tried a 20 amp GFCI outlet with 20 amp plug and switched out the 14/3 cord to 12/3 cord and the GFI still tripped when I hit the pump button (it is a new pump ) . This is a Hudson Bay spa and the warranty does not cover labor just parts they help you trouble shoot spa and repair it.(sigh). So lets start from the beginning I had a 220 amp hot tub hand me down from my dad had that for two years before internal parts started to break down . I used that 220 ling to make a sub panel in garage . have it grounded to out side ground rod and attached to ground to plumbing in cellar what i think might be the problem is my Neutral wire is not floating it is grounded to panel and from I have heard this needs to be isolated is that true ? BUT then comes the question I have used it for three month when I got it with no GFI problems now all of a sudden GFI is tripping HMMMM Temp limit sensor how do you test that ?

 

Only a detached garage would require a ground rod and a connection from the sub panel to the water pipes is not correct. Only the main panel is connected to the water pipes.

From your main panel to the sub panel should be 4 wires..... two hots, a neutral and a ground. Since that was an existing 220v line.... you probably only have two hots and a ground/neutral combo. That wiring is not approved for a spa.

With that being said.... a GFI will not trip from a combined ground/neutral before it. After the GFI device the neutral and ground must remain separate.

The only true way to diagnose the problem is with a meter. A semi inexpensive one will work ok. You need to locate what is leaking to ground. After the GFI..... any leakage from either the hot or the neutral to ground will trip the device.

You said the spa works fine in a regular/non GFI receptacle. That tells me what you are looking for is a leakage between neutral and ground as this type of short will not trip a circuit breaker. A direct short from hot to ground would cause a circuit breaker to trip.

 

Hey Sorry for late reply Few question since you seem to know the most :
Hot tub runs great without GFCI and plugged directly into circuit (I know this is not recommended) I just got new GFCI 20 amp plug hooked it up and it tripped to seems to trip when the start up load for pump starts . I have dedicated circuit for hot tub with 20 amp circuit breaker and plug outlet . I tested the outlet with a Plug circuit tester and it says it is wired correctly. Someone here said the neutral in the circuit breaker box needs to be isolated from the ground for a GFCI to function is this correct? Before I go any further I had a 220 amp circuit (two phase) for old hot tub in garage I used that twisted 4 gauge 4 wire to hook up a two circuit breaker box in Garage 1 15 amp for outlets on bench and one 20 amp for the hot tub . I do have a ground pole outside 6 feet down and have ground to plumbing in house . I do not think the Neutral is isolated from the ground that is why I ask the question .

 

Ok I have four wires two hot one neutral and one bare ground wire Neutral is on bus bar (not sure if it is isolated) ground is for bare copper wire ground bar. Now also FYI Hot tub worked for 4 months before GFCI problems ...

 

I'm not quite following you. You mentioned 20A GFI plug. Does the spa have a GFI on it's power cord and you are plugging that into a GFI protected circuit ?

When wiring from a main panel...... the neutral and ground connect to the same place in the main panel but at the sub panel end..... the neutral needs to connect to a bar that is not connected or bonded to ground. The ground goes to a bar directly screwed into the metal box.

With any wiring after a GFI the neutral and the ground cannot touch or the breaker will randomly trip.

 

?I tried using GFCI 20 amp plug also and same thing happened it tripped GFCI plug. Ok from the sub box do the Neutral and ground need to be isolated from each other? And or the Neutral be isolated from the Sub box? Still do not know why it did not trip in the four months of use I had.

 

The neutral needs to be isolated/insulated from ground in the sub box. Sounds like you may be still having a problem somewhere in the hot tub.

 

A plug or a 20A receptacle. The plug goes into the receptacle.

Ok... I think we've established that you have a regular breaker in the panel feeding a GFI receptacle. That GFI receptacle is tripping now ONLY when the motor starts. That pretty much eliminates a wiring problem to the GFI. Since load doesn't trip a GFI..... increasing the receptacle size from 15A to 20A won't help the issue.

Have you tried to start the spa without the pump plugged in ?
An internal leak to ground within the spa may not be easy to find.

I've worked on many spas and have found numerous problems. Without me actually working on it.... it's hard to tell someone else what to do or look for. I use current meters in the hot and neutral lines to check for imbalances.

Since the spa is under a year old.... what services can the manufacturer or place of purchase provide ?

 

Ok I performed test when I replaced Pump(per service center) they sent new pump with pigtail plug on it . I took a picture of plug when I disconnected it to make sure I oriented it correctly. I did run a test from plug and getting 115 volts from both high and low speed load for pump hitting the switch while pump unhooked did not trip GFCI . Ground to pump is attached to same ground bar as before. I am going to call them on Monday and tell them GFCI still tripping they say they can run me through troubleshooting which would be good idea anyway need to learn this .

 

I unhooked everything from my spa panel and GFCI is ok when I hook it up while it is laying on a piece of wood and is not mounted to the spa metal brackets. Next, I mount one of the side metal brackets to the metal panel box and GFCI is ok until the bracket touch's the ground. Do I have a hot wire to ground leak somewhere? Maybe I need to unhook more wires inside the box? So far all plugs to motors, lights are unhooked. heater element is unhooked, ozone unhooked, fan unhooked. not much left. Could something on the board be causing it?

 

Pictures might help. .

 

It would be a neutral to ground leak or connection. A hot to ground connection would create sparks.
Yes.... something on the board could cause it.

How-to-insert-pictures.