Problems with my hot tub

[Marc19780]

Hi I'm wondering if anyone has had this problem, my hot tub trips the rcd breaker when I turn the heater on, I've changed the heater and it did the same, everything else runs fine pumps blower etc, then I was told it was the heat relay on main board that has gone. So I managed to get a new main board had an electrician wire it in then soon as I tried to heat it up it's tripped out again. Any help will be grateful

[bud16415]

Hi I'm wondering if anyone has had this problem, my hot tub trips the rcd breaker when I turn the heater on, I've changed the heater and it did the same, everything else runs fine pumps blower etc, then I was told it was the heat relay on main board that has gone. So I managed to get a new main board had an electrician wire it in then soon as I tried to heat it up it's tripped out again. Any help will be grateful

I’m no hot tub electrical expert but no one gave your question a go so I will offer my 2 cents.

The RCD / GFCI breaker is very sensitive to current imbalance. That is how it protects you in the tub with 240v and a tub of water. The breaker aspect looks for over current draw and the GFCI looks for a slight change in current in to current out. In other words any slight leakage to ground will trip it. In the case of protecting you it will trip within the half cycle if the hot line came in contact with you and your path to ground and you wouldn’t get a shock it would be so instant.

Some place I would suspect some leakage of current to a part of the tub that is grounded or it could be even in the power lines to the tub or in the GFCI itself.

Just a wild idea as it was working and you changed the heater and now have the problem I would start looking at the heater. If you disconnect the heater and insulate the ends and power the tub up what happens.   

[Tman122]

Hi I'm wondering if anyone has had this problem, my hot tub trips the rcd breaker when I turn the heater on, I've changed the heater and it did the same, everything else runs fine pumps blower etc, then I was told it was the heat relay on main board that has gone. So I managed to get a new main board had an electrician wire it in then soon as I tried to heat it up it's tripped out again. Any help will be grateful

I’m no hot tub electrical expert but no one gave your question a go so I will offer my 2 cents.

The RCD / GFCI breaker is very sensitive to current imbalance. That is how it protects you in the tub with 240v and a tub of water. The breaker aspect looks for over current draw and the GFCI looks for a slight change in current in to current out. In other words any slight leakage to ground will trip it. In the case of protecting you it will trip within the half cycle if the hot line came in contact with you and your path to ground and you wouldn’t get a shock it would be so instant.

Some place I would suspect some leakage of current to a part of the tub that is grounded or it could be even in the power lines to the tub or in the GFCI itself.

Just a wild idea as it was working and you changed the heater and now have the problem I would start looking at the heater. If you disconnect the heater and insulate the ends and power the tub up what happens.

Yea, if it trips again

then isolate the lines from the gfci to the board. Check continuity. Then the breaker. But be careful it's 220V!!

[bud16415]

Hi I'm wondering if anyone has had this problem, my hot tub trips the rcd breaker when I turn the heater on, I've changed the heater and it did the same, everything else runs fine pumps blower etc, then I was told it was the heat relay on main board that has gone. So I managed to get a new main board had an electrician wire it in then soon as I tried to heat it up it's tripped out again. Any help will be grateful

I’m no hot tub electrical expert but no one gave your question a go so I will offer my 2 cents.

The RCD / GFCI breaker is very sensitive to current imbalance. That is how it protects you in the tub with 240v and a tub of water. The breaker aspect looks for over current draw and the GFCI looks for a slight change in current in to current out. In other words any slight leakage to ground will trip it. In the case of protecting you it will trip within the half cycle if the hot line came in contact with you and your path to ground and you wouldn’t get a shock it would be so instant.

Some place I would suspect some leakage of current to a part of the tub that is grounded or it could be even in the power lines to the tub or in the GFCI itself.

Just a wild idea as it was working and you changed the heater and now have the problem I would start looking at the heater. If you disconnect the heater and insulate the ends and power the tub up what happens.

Yea, if it trips again

then isolate the lines from the gfci to the board. Check continuity. Then the breaker. But be careful it's 220V!!

Just for my own understanding as well as the OP’s.

The lines from GFCI breaker you would disconnect at the termination point on the hot tubs panel and protect the ends? Then turn the breaker on?  What continuity would you check? If the GFCI breaker then still tripped you would try it again by disconnecting the other end of the lines feeding the tub?

Those steps should rule out a wiring problem to the tub or a bad GFCI breaker. But he doesn’t get the fault until he powers the heater on. 

[Marc19780]

Thanks for your replies hopefully I'll eventually find out the problem

[Marc19780]

Yeah I only get the problem when I turn the heater on, and I've replaced the heater and it's still doing the same, I'm wondering if it's a weak breaker or the heater cable could be damaged as I only replaced the heater not the cable, I'm scratching my head with this one

[bud16415]

Well you know it only happens when you turn on the heaterthe GFCI breaker is on and not tripping so that rules that out and the wires running to the tub. When you call for heat it trips that is when the wires to the heater are being powered up. Disconnecting them from the heater itself and insulating the ends from touching anything and then call for heat would tell you if there was a ground or short in those wires causing the GFCI to trip.

Again one of two things is tripping it. Too much current or a GFCI condition where the current isn’t balanced in both legs.

I’m sure someone here can tell you what the resistance of the heater should be and you could check that with your meter. That would be a indication of current draw.

There is always the chance you got a bad heater as well.

[Pers Onal]

Umm, the breaker might be going.

GFCI breakers work to design, but individual breakers can be more than a little flaky.

They also will tend to age (not in theory, but not that uncommon in practice.)

I had to replace a GFCI breaker after ten years or so. The replacement wouldn't go for more than two weeks without tripping.

Took it back to Home Depot, got another no questions asked.

It has been working for eight or ten years.

Don't know if that will solve your problem, but is simply food for thought.