Nuisance GFCI Tripping Off

This Article is to give some Ideas of why your Hot Tub GFCI Trips, we don't encourage anyone to Attempt their own Hot Tub Repair.

The most common reason for Tripping the GFCI is a Failing Heating Element. The Element is in Water that most likely is Acidic, below 7.6 or 7.5 PH. I know that seems high but when you add in the Velocity of the Water passing over the Element, when on High Speed, it could increase Corrosion. The Bulk Heads where the Mounting Flange is attached begins to leak or seep.

Just a drop of water will the GFCI to trip off. Remember from the GFCI Article it only takes 5 mA (0.005 A) of current leakage to Trip off the GFCI.

Leaking Pump Seals will Throw Water that could get into The Pump Motor. Again that may be caused by Low Water PH. Seals will not last very long if yu mainti=ain poor water chemistry.

DIY

Working on a Hot Tub is not a DIY Project. Most Hot Tub have 220 volts from a High Current GFCI Breaker, 30 to 50 Amps. This Voltage and the Current Value is Dangerous and Could under certain conditions Kill you. Electrical Shocks are not to be taken as a joking matter.

In all the years working on Tubs, usually with the Power On I never got an Electrical Shock. I had and still have a Great Respect for Electricity. After 79 words to discourage you from doing this yourself Call a Professional. I have warned you not to do this yourself.

Locating the cause of a GFCI Trip

First I would determine if the Trip occurs as soon as you turn on the Breaker or does it take a couple of seconds or minutes

If possible, I would Disconnect by unplugging all of the Plugs going to the Pumps, Blower, Lights, and All Accessories. If all are Disconnected and the Breaker still will not Set. Then I would go to the Heater. Going to Heating Element is a Short Cut but if the GFCI still Trips, then I would Disconnect the Power Wires from the Terminal Block inside the Control Box. This would Isolate the Problem to the Wires, Conduit and Breaker.

No Trip, at least right away. I asked the Home owner to check the Breaker every day. After 11 days the GFCI Tripped. That was good enough for me. I called the Electrician to replace the Wires. Sure enough there was a nick in the Insulation from the original Installation.

The Temperature differences outside and Inside the Attic would cause some amounts of Condensation in the Conduit, that is what caused the Trip of the GFCI.

A Heating Element failure usually will trip the GFCI right away. I would Check to see if the Trip was from the Heating Element by carefully disconnecting the wires or strip going to the Element, then reset the Breaker. If the Breaker Set and ever thing works then it probably is the element.

The Heating Element

Heating Elements are in the Stainless Steel Tube Housing usually behind the Equipment Box. Replacing the Element is pretty Basic unless the 2 - 3/4" Nuts that fasten the Element to the Heating Manifold are corroded from leaks, then the Nuts will have to be cut off or the Element Electrical connectors Drilled out. I have done both it ways even in the Field.

If I had the Manifold (Tube) in my Shop I would use the Drill Press and Drill them out. Cutting the Nuts can be Tricky because you can't cut the Housing itself, it must be a clean cut and maybe not all the way through and just break the Nut open if possible.

The New Element will have O-rings that fit into a Groove on the Element, they seal the Element and keep the Water inside the Tube. I would slightly lube the O-rings and the Threads on the Element with water proof lubricant, this allows everything to get tight, smoothly. Too much may cause the GFCI to Trip. If the Lube gets up on the Terminal for the Electrical Supply it will cause the GFCI To Trip.

Slow GFCI Trip

If the Breaker does not Trip right away but Trips in 30 or 40 minutes I would look at the Breaker or better yet if you have an Infrared Thermometer aim it at the Breaker and check that temperature with another.

It is obviously going to warmer than a Breaker with a Lower Current rating or a Breaker not in use. You just need to get an idea of what the Temp is with other Breakers like the AC. If the Hot Tub Breaker is much Hotter that the others it could be the wires leaving the Breaker became loose and get hot and that trips the Breaker.

The Wires may have already Burned and melted the Lug Tightening Screw. If that has happened that the Breaker must be replaced and the wires cut back, do away with the Burned Ends. The new connection will be weak if this is not done.

Other Causes

If this is a New Install and the 1st time you turn on the Breaker and it Trips right away, it could be the way the GFCI Breaker is Hooked up. There were a few years that I would get at least 2 Calls a week for this Problem.

A novice Electrician is of the Belief that all the White Wires go to the Common Bus Bar and Don't read the Instruction for the GFCI. The Curled up White Wire goes to the Common Bus Bar and the Common Wire Coming from the Spa goes into the GFCI Breaker where it is marked.

What if there no Common Wire needed for the Hot Tub? Hook up the 2 Power Leads as Normal and leave out the White Wire. You still Hook up the Curly White Wire from the GFCI to the Common Bus Bar. You still have the GFCI Protection if you are not using a White Common Wire.

You may ask the question, why is there no Terminal on my Hot Tub for a White Wire? The White wire is only needed for a Motor or Accessory that operates on 110VAC. When there is no need for a Common Wire everything in Hot Tub is operated at 220VAC.

“Whether you think you can or you think you can't, you're right”
Henry Ford