Rheem Crosswind-50-I pool heater GFCI Tripping

[DwilliamsFBPS]

I’m wiring a Rheem Crosswind 50-I pool heater. I installed a 2 pole 20A GE GFCI circuit breaker that is HACR rated. The unit will start but when the compressor turns on, the breaker trips.

The unit only requires 240v with no neutral. The pigtail of the GFCI breaker is on the neutral bar of a sub panel with separated neutrals and grounds.

Any help is appreciated.

 

[Little Bill]

I would start with putting in a regular breaker and see if it holds. This would just be for testing.

 

[kwired]

Since you mention compressor, I kind of presume this is a heat pump type of heater. Does it happen to have variable speed compressor?

Variable speed motor/drives are known not to play well with GFCI's in many different applications.

 

[retirede]

Since you mention compressor, I kind of presume this is a heat pump type of heater. Does it happen to have variable speed compressor?

Variable speed motor/drives are known not to play well with GFCI's in many different applications.

The “I” suffix in the model means “Inverter”. On-off models have an “O” suffix.

I suspect you’re on the right track.

 

[kwired]

The “I” suffix in the model means “Inverter”. On-off models have an “O” suffix.

I suspect you’re on the right track.

This also equipment that likely did not require GFCI protection before 2020 NEC? (I need to confirm but I don't think it was required) Manufacturer maybe hasn't caught up with that and made it so it is compatible with GFCI? Or might specify a particular GFCI unit that it will work with? Pentair I know has pool pumps and such that they only recommend using Siemens GFCI breakers with. Why those hold but not others IDK.

 

[retirede]

This also equipment that likely did not require GFCI protection before 2020 NEC? (I need to confirm but I don't think it was required) Manufacturer maybe hasn't caught up with that and made it so it is compatible with GFCI? Or might specify a particular GFCI unit that it will work with? Pentair I know has pool pumps and such that they only recommend using Siemens GFCI breakers with. Why those hold but not others IDK.

I agree. Pool heat pumps, per se, don’t require GFCI protection. The 2020 changes for protecting outdoor outlets invoke the requirement.

 

[DwilliamsFBPS]

I would start with putting in a regular breaker and see if it holds. This would just be for testing.

When I disconnect the neutral pigtail it holds…. So that tells me it’s not overload.

 

[DwilliamsFBPS]

The “I” suffix in the model means “Inverter”. On-off models have an “O” suffix.

I suspect you’re on the right track.

Tech support told me they don’t play well with GFCI’s, but that doesn’t help me meet the code requirement.

 

[Little Bill]

When I disconnect the neutral pigtail it holds…. So that tells me it’s not overload.

That's not telling you anything about overload, it's just disconnecting the breaker's internal circuit. Also, if the unit doesn't require a neutral, there would be no neutral load to overload.
My suggestion for putting in a regular breaker was to see if there was a short, not overload.

Since the breaker's internal circuit was disconnected, it couldn't sense any ground fault. So it sounds like the unit just doesn't like GFCIs because of the inverter.

 

[kwired]

That's not telling you anything about overload, it's just disconnecting the breaker's internal circuit. Also, if the unit doesn't require a neutral, there would be no neutral load to overload.
My suggestion for putting in a regular breaker was to see if there was a short, not overload.

Since the breaker's internal circuit was disconnected, it couldn't sense any ground fault. So it sounds like the unit just doesn't like GFCIs because of the inverter.

I agree with this. kind of did the same thing as disconnecting one conductor from coil of a contactor then expecting it to do it's normal thing with the controlled circuit.

 

[DwilliamsFBPS]

That's not telling you anything about overload, it's just disconnecting the breaker's internal circuit. Also, if the unit doesn't require a neutral, there would be no neutral load to overload.
My suggestion for putting in a regular breaker was to see if there was a short, not overload.

Since the breaker's internal circuit was disconnected, it couldn't sense any ground fault. So it sounds like the unit just doesn't like GFCIs because of the inverter.

Agreed, miss wrote. I was going to state that essentially I would think disconnecting the neutral pigtail would eliminate the ground fault protection to the breaker.
I don’t have much knowledge on how a 2 pole GFCI breaker without a neutral would work as I’ve always known GFCI to measure any imbalance on the neutral conductor. I would assume with only 2 phases the breaker would measure any imbalance in the (2) hot conducturs?

I appreciate the responses and help.

 

[Little Bill]

Agreed, miss wrote. I was going to state that essentially I would think disconnecting the neutral pigtail would eliminate the ground fault protection to the breaker.
I don’t have much knowledge on how a 2 pole GFCI breaker without a neutral would work as I’ve always known GFCI to measure any imbalance on the neutral conductor. I would assume with only 2 phases the breaker would measure any imbalance in the (2) hot conducturs?

I appreciate the responses and help.

Yes, a 2-pole GFCI breaker monitors the current coming/going on each leg if no neutral load on it.

 

[tthh]

Agreed, miss wrote. I was going to state that essentially I would think disconnecting the neutral pigtail would eliminate the ground fault protection to the breaker.
I don’t have much knowledge on how a 2 pole GFCI breaker without a neutral would work as I’ve always known GFCI to measure any imbalance on the neutral conductor. I would assume with only 2 phases the breaker would measure any imbalance in the (2) hot conducturs?

I appreciate the responses and help.

I would also assume that removing the neutral pigtail removes the power for the internal GFCI circuitry...and one would further assume that the breaker at least works as well as a non-GFCI in that case.

 

[kwired]

Agreed, miss wrote. I was going to state that essentially I would think disconnecting the neutral pigtail would eliminate the ground fault protection to the breaker.
I don’t have much knowledge on how a 2 pole GFCI breaker without a neutral would work as I’ve always known GFCI to measure any imbalance on the neutral conductor. I would assume with only 2 phases the breaker would measure any imbalance in the (2) hot conducturs?

I appreciate the responses and help.

The logic circuit that does the GFCI monitoring is powered by one the ungrounded conductors and the line side neutral pigtail. By disconnecting that pigtail you have no power to the logic circuit and that disables the GFCI function. The thing will still trip on thermal magnetic function though, but cost a lot less to just purchase a standard breaker than a GFCI breaker.

 

[kwired]

I would also assume that removing the neutral pigtail removes the power for the internal GFCI circuitry...and one would further assume that the breaker at least works as well as a non-GFCI in that case.

it does. I've done some checking in the past. Lose an ungrounded supply conductor can do the same if it is the one the other side of the GFCI circuitry. Leaving you with power still applied but no GFCI protection. GFCI receptacles sort of have addressed this to some extent, never seen a GFCI breaker yet that will lock out if missing input power to the electronics. But most them receptacles do what they do for line/load reversal protection, which usually isn't something so easy to do with a GFCI breaker unless you are straight out backfeeding it. The receptacles may continue to work as long as they haven't tripped and you for whatever reason reversed line/load conductors, but once tripped they need to see proper line side voltage before they will reset.