Hot tub breaker size

[blueheels2]

Hot tub has 48 amp nameplate. Nameplate doesn’t list breaker size. I’m assuming 60 amp. 125% of nameplate rating.

But what is the code justification for 125% of nameplate? 422.10 (A).

 

[ptonsparky]

Hot tub has 48 amp nameplate. Nameplate doesn’t list breaker size. I’m assuming 60 amp. 125% of nameplate rating.

But what is the code justification for 125% of nameplate? 422.10 (A).

Quote the nameplate exactly or post a picture of it.

 

[infinity]

A hot tub is not a continuous load so no 125% factor required. Could use a 50 amp circuit.

 

[Little Bill]

A hot tub is not a continuous load so no 125% factor required. Could use a 50 amp circuit.

All the tubs I've installed that said 48A, the specs said to use a 60A breaker. I assumed it was due to 125% for largest motor, or they could be considered a continuous load as they could be on for 3 hours or more without cycling off when heating from initial fill up with cold water. Same thing for one saying 40A, they said 50A breaker. Both cases come out to be exactly 125% of rating.
40x125% = 50A
48x125% =60A

ETA: I just found a code section in 680. Hot tubs are listed in that section and have electric heaters, so I see this as applying.

680.10 Electric Pool Water Heaters. All electric pool water
heaters shall have the heating elements subdivided into loads
not exceeding 48 amperes and protected at not over
60 amperes. The ampacity of the branch-circuit conductors and
the rating or setting of overcurrent protective devices shall not
be less than 125 percent of the total nameplate-rated load.

 

[david luchini]

ETA: I just found a code section in 680. Hot tubs are listed in that section and have electric heaters, so I see this as applying.

I don't see that section applying. It's specifically for water heaters for permanently installed pools.

 

[Little Bill]

I don't see that section applying. It's specifically for water heaters for permanently installed pools.

I don't see anything that says it's specifically for permanently installed pools. Hot tub wiring is to be according to Part I of 680. The section I quoted is in Part I. Part 2 says "Permanently Installed Pools"

 

[david luchini]

I don't see anything that says it's specifically for permanently installed pools. Hot tub wiring is to be according to Part I of 680. The section I quoted is in Part I. Part 2 says "Permanently Installed Pools"

OK...it's specifically for 'electric pool water heaters.' A Spa or Hot Tub is not an 'electric pool water heater.'

 

[infinity]

I agree just follow the installation instructions but there is no way that a hot tub is a continuous load. The heater, pumps, bubblers, lights, etc. will not all run continuously for 3 or more hours all at the same time.

 

[Little Bill]

OK...it's specifically for 'electric pool water heaters.' A Spa or Hot Tub is not an 'electric pool water heater.'

If it were meant for just permanently installed pools, it would be listed under Part II.
Here is the scope of 680, notice it says "hot tubs".

680.1 Scope. The provisions of this article apply to the
construction and installation of electrical wiring for, and equipment
in or adjacent to, all swimming, wading, therapeutic, and
decorative pools; fountains; hot tubs; spas; and hydromassage
bathtubs, whether permanently installed or storable, and to
metallic auxiliary equipment, such as pumps, filters, and similar
equipment. The term body of water used throughout Part I
applies to all bodies of water covered in this scope unless otherwise
amended.

 

[david luchini]

If it were meant for just permanently installed pools, it would be listed under Part II.
Here is the scope of 680, notice it says "hot tubs".

But a hot tub is not a water heater.

 

[Little Bill]

But a hot tub is not a water heater.

But it has a water heater. I'm just trying to see what justification the mfg had in specifying the 125%. All I know for sure is what I read in their specs and those equaled adding the 125%. That's all I have.

 

[retirede]

But it has a water heater. I'm just trying to see what justification the mfg had in specifying the 125%. All I know for sure is what I read in their specs and those equaled adding the 125%. That's all I have.

If the manufacturer calls for a 60A breaker, the rest of the discussion is irrelevant.

 

[infinity]

If the manufacturer calls for a 60A breaker, the rest of the discussion is irrelevant.

Agreed, but for arguments sake what if they don't? What would be the minimum size branch circuit allowed?