Hot Tub GFCI Keeps Tripping? What to Check, and Where to Stop

A tripped GFCI is the one hot tub fault I don't argue with. It's the device that stands between a fault in the heater or a pump and the people sitting in the water next to it.

That doesn't mean every trip is a disaster. A Balboa control trips its own GFCI once, on purpose. A brand-new circuit can be wired so that it trips the moment it's switched on. And a tired GFCI breaker can be the fault itself. But the manuals agree on where the owner's part ends, and it ends early.

Everything below comes from the spa makers' owner's manuals and websites, from Balboa and Gecko, whose controls are in the Jacuzzi, Sundance, Marquis, Cal Spas, Master Spas and Hydropool tubs quoted here, from the GFCI breaker makers, and from CPSC and OSHA. Where they disagree, I say so.

Key takeaways

• A GFCI cuts the power when current leaks to ground. CPSC says it reacts to as little as 0.006 amperes.
• Reset it once, the way your manual says: wait 30 seconds, then switch it fully off and back on. If it trips again or won't reset, the tub stays off.
• Balboa controls trip the GFCI once, 1 to 7 days after start-up, to test it. After that, Balboa says any trip means power off until it's fixed.
• A new installation that trips at once points to the wiring. Master Spas and Bullfrog both name the load neutral.
• Master Spas says a failed heater trips the GFCI the majority of the time.
• Never bypass the GFCI and never use an extension cord. Every maker that mentions either forbids it.

What a trip means

A GFCI watches for current leaking to ground. CPSC defines a ground fault as "an unintentional electrical path between a power source and a grounded surface." A GFCI compares the current going out with the current coming back. CPSC says it trips if they differ by as little as 0.006 amperes, and OSHA puts it at about 5 mA, cut off within as little as 1/40 of a second. Hot Spring's manual says its GFCIs detect 5 mA, give or take 1.

A GFCI breaker also trips on overload. CPSC says a breaker with a built-in GFCI protects against both a ground fault and a circuit overload. Leviton's breakers show which it was with their indicator lights. So a trip isn't always a ground fault, but you can't tell which from the deck.

The GFCI and the house breaker mean different things. Hot Spring's manuals say to check the spa's GFCI first, then the house breaker that feeds it. If the house breaker has tripped, the circuit was overloaded or there's a ground fault between the panel and the spa's subpanel or outlet, and that's an electrician's job. The pool pump guide makes the same split for a pump.

	What it points to	Who fixes it
One trip, 1 to 7 days after start-up (Balboa control)	The control testing its GFCI	You: reset it once
Trips the moment a new circuit is switched on	Wiring, such as the load neutral	The electrician who wired it
Trips again after a reset, or won’t reset	A ground fault in the spa or the circuit	Service technician or electrician
Trips with an HL message (Gecko control)	The heater overheated, and the pack cut the power	Service technician
House breaker trips on a 115-volt tub	An overloaded or shared circuit, or wiring	Electrician

Is it the tub testing itself?

Balboa's controls trip the GFCI on purpose. Balboa's TP500S and TP600 guides say that within 1 to 7 days after start-up, the spa will trip the GFCI to test it, and the GFCI then has to be reset. The TP200 guide says "may," and says not every control does it. Balboa adds that resetting the test feature before moving a tub makes it test again at the new site.

That test only happens once. After it, Balboa says, "any subsequent GFCI trips will indicate a ground fault or other unsafe condition and the power to the spa must be shut off until a service person can correct the problem."

If the test fails, the panel says so. Balboa's message reads "GFCI Failure - System Could Not Test/Trip the GFCI," with the code M036, and says it may indicate an unsafe installation. The Jacuzzi, Sundance, Marquis and Cal Spas manuals carry the same code. Jacuzzi's J-300, Sundance's 880 and Marquis' Crown also have a GFCI test you can run from the panel, which trips the breaker and leaves you to reset it.

A Gecko pack trips it on an overheat. Gecko's troubleshooting guide says its Y-series packs have "a GFCI/RCD tripper circuit in case an HL error occurs." HL means the water in the heater reached 119°F. That's a heater or flow problem, and the not-heating guide has the checks for it.

A new installation that trips at once

Have the load neutral checked first. On a new circuit, Master Spas says, "an instantly tripping GFCI may likely be caused by improper wiring of the load neutral" between the GFCI and the spa. Bullfrog's site says the spa's white neutral must go to the load neutral terminal on the GFCI breaker. If it goes to the panel's neutral bar instead, the breaker trips at start-up. ThermoSpas' manual says the same, and Leviton's breaker instructions say not to ground the neutral on the load side.

Hot Spring and Caldera say that if the breakers trip immediately, verify the wires are correctly connected. Hot Spring also warns that connecting the hot wire to the neutral terminal will cause irreversible damage to the control box.

Gecko's breaker setting. Gecko's start-up guide says the pack has to be told the GFCI's rating, to reduce nuisance trips, and that the setting is 80 percent of the breaker's capacity. A wrong setting is the installer's to fix.

Undersized or shared circuits. Master Spas says wire that's too small may continually trip breakers. Hot Spring and Master Spas both say a tub on a circuit it shares with other things can cause "nuisance tripping" at the main panel.

All of that is the electrician's work. The makers' manuals put the installation in the hands of a qualified or licensed electrician.

What the makers name as causes

The manuals say less about this than you'd expect. Hot Spring's, Caldera's, Jacuzzi's and Sundance's name no component at all; they say reset it, and call for service if it won't reset.

• The heater. Master Spas says that when a heater has failed, "the majority of the time it will trip the GFCI breaker." Hot Spring's website calls heating elements among the most common causes. ThermoSpas lists the heater with the controller and an improperly wired ground.
• Water where it shouldn't be. Bullfrog says water in the equipment compartment can trip the breaker. Master Spas says that if water is getting into any component in the equipment area, turn off the breaker and refer it to qualified service. Hot Spring says to protect a cord GFCI from rain.
• The breaker itself. Master Spas and Bullfrog both list a faulty or defective GFCI breaker. Hydropool recommends a new Siemens GFCI and says "Other GFCI’s and older Siemens GFCI’s may have tripping issues." Jacuzzi and Sundance recommend Square D.
• Any component. Bullfrog's site, ThermoSpas and Gecko all describe unplugging pumps, blowers, lights and the ozonator one at a time to find the one that trips it.

Where the owner's part ends

The makers don't agree on how far an owner should go, and this is the biggest split on the page.

The manuals say: reset, then call. Hot Spring and Caldera tell you not to open the electrical control box, because there are no user-serviceable parts inside. If the GFCI won't reset, they say it may mean a ground fault, and to call an authorized service technician. Master Spas says not to service the tub yourself, because opening covers may expose you to dangerous voltage. Gecko says its packs contain no user-serviceable parts. Balboa says not to attempt service of its control system.

Some of the makers' own pages go further. Hot Spring's website tells owners to disconnect components and test them one at a time, tug on connections, and feel parts for warmth after unplugging the tub. ThermoSpas' manual walks the owner through unplugging components inside the pack. Bullfrog's site describes the same process, but opens with a warning that you must be a qualified electrician or service technician to diagnose it.

My rule follows the manuals: I reset a GFCI once, and if it trips again, the tub stays off until someone qualified has opened the pack. A component that trips a GFCI is leaking current somewhere near water, and that's not the moment to start unplugging things by hand.

1. 1

   Find out what tripped

   2 min

   Check the GFCI breaker in the spa's subpanel, or the GFCI on a plug-in tub's cord. Then check the house breaker that feeds it. Hot Spring's manuals say a tripped house breaker means an overloaded circuit or a ground fault before the spa, and that's for an electrician.

   Mark done
2. 2

   Read the control panel

   1 min

   Look for a message before you reset anything. On a Balboa-type control, M036 means its GFCI test failed. On a Gecko pack, an HL message means the heater overheated and the pack may have tripped the GFCI itself. Note what it says for the technician.

   Mark done
3. 3

   Look for water, without opening anything

   2 min

   Look at the cabinet and the cord GFCI from outside. If water is getting into the equipment area, leave the power off and call for service, as Master Spas says. Don't open the control box: Hot Spring and Master Spas both say not to.

   Mark done
4. 4

   Reset it once, properly

   1 min

   Hot Spring says to wait 30 seconds, then switch the breaker fully off and back on. Cal Spas says the same: full off, wait a moment, then on. On a plug-in tub, press RESET on the cord GFCI.

   Mark done
5. 5

   If it trips again, stop

   5 min

   Leave the tub off and call an authorized service technician or an electrician. Siemens says a breaker that trips again after a reset means a fault still exists on the circuit. If it's freezing, read the winter guide while you wait: Balboa says to drain a tub whose GFCI won't reset, and Bullfrog's site says don't.

   Mark done

Testing it

The makers agree it must be tested and disagree on how often:

• Before each use: Caldera, Bullfrog, Master Spas, Intex and Bestway, and the caution printed in Balboa's guides.
• Monthly: Hydropool and CPSC. Balboa's and Cal Spas' controls show a reminder about every 30 days. Leviton says to test its breakers monthly.
• Both: Hot Spring says before each use in one part of its manual and once a month in another. Marquis does the same.
• No interval: Jacuzzi, Sundance, Arctic and ThermoSpas give none for the owner.

CPSC adds two more times to test: after installation and after a power failure, because blackouts can damage a GFCI. Hot Spring notes that a tripped cord GFCI resets itself when the power comes back after an outage, so a tub that comes back on by itself hasn't been tested.

How to test it. With the tub running, press TEST. The tub should stop, and on a cord GFCI the light should go out. Wait 30 seconds, then reset it, by switching a breaker fully off and on or pressing RESET on a cord. Hot Spring and Bullfrog both say that if it doesn't work that way, there may be an electrical fault and a risk of shock: disconnect the power until it's been fixed. Bullfrog says the GFCI test belongs to a licensed electrician, while also telling owners to test before each use.

Go deeperTub on, but no heat?The heater's checks in order, from the set point to the high-limit.

Plug-in and inflatable tubs

Plug-in hard tubs. Hot Spring's 115-volt tubs need a dedicated GFCI-protected circuit, 15 or 20 amps by model. Its Hot Spot manual says a tub on a circuit it shares with other things will cause "nuisance tripping" at the main panel. Jacuzzi says its 120-volt tub must run on the supplied cord at its original length, or be hard-wired for longer runs.

Inflatable tubs. Intex and Bestway both say to test the cord's GFCI before each use, and not to use the tub if the test fails. Intex says its spa draws up to 13 amps, so if the house breaker trips, check that nothing else large is on the same circuit. Intex also says not to use the spa in rain or thunder. Bestway's plug has a yellow light: flashing means its GFCI function is compromised, and steady means it has detected high temperature. In both cases, Bestway says, stop using it if the light stays on.

Where the makers disagree

• Who troubleshoots. Hot Spring's, Master Spas', Balboa's and Gecko's manuals say a technician. Hot Spring's website, ThermoSpas' manual and Bullfrog's site describe owners unplugging components.
• After a trip. Hot Spring and Caldera say reset, and call if it won't. Balboa says any trip after its start-up test means power off. Siemens says reset once, then call. No one gives a number of attempts.
• How often to test. Before each use, monthly, or both in the same manual.
• Who tests. Bullfrog says a licensed electrician does the GFCI test procedure, and also that it must be tested before each use. Balboa expects the owner to be trained to do it.
• Which breaker. Hydropool recommends Siemens; Jacuzzi and Sundance recommend Square D.
• Distance. Hot Spring's manuals put the disconnect at least 5 feet from the tub. Its website says the code requires six. For the 115-volt outlet, its Highlife manual says no closer than 6 feet and its Hot Spot manual says 5.
• A tripped GFCI in freezing weather. Balboa says drain the tub if it won't reset. Bullfrog's site says don't drain, and use a small heater in the cabinet. Hydropool also says a low-wattage heater while you wait for service.

Frequently asked questions

Why does my hot tub GFCI keep tripping?

Because current is leaking to ground somewhere, or the circuit is wired wrong. Master Spas says a failed heater causes it the majority of the time, and names faulty breakers, components, power fluctuations and wiring. Bullfrog adds water in the equipment compartment. A new installation that trips at once points to the load neutral wiring.

How many times should I reset a tripping GFCI?

No maker gives a number. Hot Spring says to reset it and call an authorized service technician if it won't reset. Siemens, a breaker maker, says that if it trips again after a reset, a fault still exists, so call an electrical contractor. Balboa says any trip after its one-time test means the power stays off until a service person fixes it.

My new hot tub tripped the GFCI a few days after it was filled. Is it broken?

Maybe not. Balboa's controls trip the GFCI once, 1 to 7 days after start-up, to prove it works, and the GFCI then has to be reset. Balboa says any trip after that test means a ground fault or other unsafe condition.

My hot tub trips the GFCI as soon as I turn it on. What's wrong?

On a new installation, the wiring. Master Spas says an instantly tripping GFCI on a new circuit may likely be the load neutral, and Bullfrog says the neutral must go to the GFCI breaker's load neutral terminal, not the neutral bar. Siemens says a real ground fault trips again immediately after a reset. Both need an electrician.

Can a bad GFCI breaker cause tripping?

Yes. Master Spas and Bullfrog both list a faulty or defective GFCI breaker as a cause. Hydropool recommends a new Siemens GFCI and says other GFCIs and older Siemens ones may have tripping issues, while Jacuzzi and Sundance recommend Square D. Replacing one is an electrician's job.

How often should I test my hot tub's GFCI?

The makers disagree. Caldera, Bullfrog, Master Spas, Intex and Bestway say before each use. Hydropool and CPSC say monthly, and Balboa and Cal Spas controls show a reminder about every 30 days. Hot Spring and Marquis say both in different parts of the same manual. CPSC also says to test after a power failure.

Can I use an extension cord for a plug-in hot tub?

No. Hot Spring, Jacuzzi, Bullfrog, Intex and Bestway all forbid it. Hot Spring says an extension cord may not be properly grounded and can starve the pump of voltage, and Bullfrog says using one voids the warranty on the equipment.