Dedicated hot tub circuit problem

[chuckers]

I installed a dedicated 50amp circuit for a hot tub about 5 years ago and it's always worked fine. The customer called me and told me that everytime the hot tub is running and someone turns on a vacuum,trash compactor,or other appliances it trips the GFCI hot tub breaker I installed. I asked him if anything had been done and he said a hot tub serviceman installed a new pump and it's been happening since then. He had a friend replace the GFCI breaker, same problem occurred. As long as nothing else is turned on the hot tub works fine. He has had PGand E out and they say their stuff is fine. Anybody have an answer?

 

[domnic]

Hot tub

Hot tub

You have a bad neutral in the service.

 

[Pierre C Belarge]

Since it has been as long as you have mentioned, and a tech was there servicing the equipment, it sounds to me like you have a service call to make. Try and determine what the tech did, as he may have done more than you expect.

Also, go back to the panel and see if the person who replaced the GFCI has not fiddled with the circuitry for the Hottub and used it to supply other items.

 

[sparkyway]

I would make it clear that the problem is not original installation related. It's should be very fixable. Start with the panel and work your way out to the hot tub since the breaker was altered. Why were you not notified about other related problems before several cooks worked in the stew? I would bet you have a bad motor that is sending current to ground. I got the impression your 5-year-old-installation was being questioned. Man, if that's the case, I'd love to get all my vehicle's woes fixed the same way! Just let them know game rules from the start and then you can deal with the issue.

 

[winnie]

I would suspect a neutral to ground fault downstream of the hot tub GFCI.

If the hot tub doesn't have any 120V loads, then such a neutral to ground fault would trip the GFCI when something _upstream_ of the GFCI causes sufficient voltage drop on the neutral.

-Jon

 

[dcspector]

I would suspect a neutral to ground fault downstream of the hot tub GFCI.

If the hot tub doesn't have any 120V loads, then such a neutral to ground fault would trip the GFCI when something _upstream_ of the GFCI causes sufficient voltage drop on the neutral.

-Jon

Jon I do agree with your post. GFCI monitors via a differential transformer the current flow so that makes good sense with VD.....

 

[Brian Oshman]

The problem is in the pump motor. It is leaking current through the armature. Had this on two occasions with my tub, the first was the circ pump which circulates water all the time. It would not trip when unplugged and just left it unplugged. The second was the main pump. It has two pumps but one also doubles as filtration duty and will run when in the filtration cycle and the other pump only runs when turned on for those jets so the primary pump gets more use and the seal wears out quicker.

The leaking seal would cause the GFI to trip. Even if the seal is not leaking, there could (and probably is) a current leak in the armature to the motor frame and it would require the motor to be replaced.

A remaufactured or rebuilt pump may have been used and it could have had a problem or it was damaged during the rebuild stage or if it is brand new it could just be a manufacturing defect.

Most control circuits are 120 volts and so is the circ pumps but the heaters and main pumps are 240.

Also, check all connections for integrity at the tub and in the panel but since the motor was changed and the problem started at that time that is the place to start.

 

[LarryFine]

Heater elements also become leaky after a while, and have intimate contact with the water.

 

[Dennis Alwon]

I asked him if anything had been done and he said a hot tub serviceman installed a new pump and it's been happening since then.

It happened after the serviceman came---that is the key. The new pump may very well be defective or some wiring got screwed up in the install. I would start there.