Hot Tub on 208V

[Little Bill]

Will a Hot Tub operate on 208V?
I know that the heaters will probably take longer to heat. I think the motors should operate but am unsure about the control board.
I hooked one up today in a house with a 1200A 3Ø service. It didn't even cross my mind until I got home. I'm so used to connecting them to 240V it didn't dawn on me till later. If there is no water in the tubs when I hook them up I just make sure the power is there and let either the HO or Spa store guys start them up. There was no water in this tub so it hasn't been started yet. I contacted the Spa mgr and he didn't know. I told him I was just informing him so he could find out if it would work before starting it up.

 

[Gary11734]

Will a Hot Tub operate on 208V?
I know that the heaters will probably take longer to heat. I think the motors should operate but am unsure about the control board.
I hooked one up today in a house with a 1200A 3Ø service. It didn't even cross my mind until I got home. I'm so used to connecting them to 240V it didn't dawn on me till later. If there is no water in the tubs when I hook them up I just make sure the power is there and let either the HO or Spa store guys start them up. There was no water in this tub so it hasn't been started yet. I contacted the Spa mgr and he didn't know. I told him I was just informing him so he could find out if it would work before starting it up.

You would assume these days that the motors are rated 208-240. The heaters, well they may need a booster if they want the rated heat based on the wattage, which I assume would be based on 240V

 

[Gary11734]

Will a Hot Tub operate on 208V?
I know that the heaters will probably take longer to heat. I think the motors should operate but am unsure about the control board.
I hooked one up today in a house with a 1200A 3Ø service. It didn't even cross my mind until I got home. I'm so used to connecting them to 240V it didn't dawn on me till later. If there is no water in the tubs when I hook them up I just make sure the power is there and let either the HO or Spa store guys start them up. There was no water in this tub so it hasn't been started yet. I contacted the Spa mgr and he didn't know. I told him I was just informing him so he could find out if it would work before starting it up.

What kind of neighborhood has three phase? Wherever it is, I guarantee its a nice one!

 

[Little Bill]

What kind of neighborhood has three phase? Wherever it is, I guarantee its a nice one!

This is one of the old "well to do neighborhoods" but it is old. The house was completely remodeled a few years back. They have a Geothermal system and that is part of why they have 3Ø. Although, to my knowledge, there is no 3Ø equipment in the house. I was told the 3Ø was just to balance the load for the POCO. IMO, the service is highly over calculated. I think this because all the panels are full and the legend shows they have individual circuits for things that normally would be combined. As an example, the basement den had separate circuits for each wall with receptacles. The outside patio had three receptacles and they were on a separate circuit. Most lighting and receptacles were separate.

 

[480sparky]

If 208v isn't listed on the label...... It will probably 'work', just may not be 'listed' for the use.

 

[texie]

Will a Hot Tub operate on 208V?
I know that the heaters will probably take longer to heat. I think the motors should operate but am unsure about the control board.
I hooked one up today in a house with a 1200A 3Ø service. It didn't even cross my mind until I got home. I'm so used to connecting them to 240V it didn't dawn on me till later. If there is no water in the tubs when I hook them up I just make sure the power is there and let either the HO or Spa store guys start them up. There was no water in this tub so it hasn't been started yet. I contacted the Spa mgr and he didn't know. I told him I was just informing him so he could find out if it would work before starting it up.

I would suppose that it could be argued that the instructions likely say a 120/240 volt supply and thus you are violating the listing. That may be a stretch. And AFAIK, all 2 pole GFCIs will work on a 208 system (unlike 1 pole units). Of course you have to live with the 25% reduction in heating capacity.

 

[LarryFine]

I would suggest that the control board or transformer (if there is one) be checked to see if there is a 208v tap.

What kind of neighborhood has three phase? Wherever it is, I guarantee its a nice one!

I have a customer with a high-leg delta service.

 

[texie]

I would suggest that the control board or transformer (if there is one) be checked to see if there is a 208v tap.


I have a customer with a high-leg delta service.

Used to be very common in the early days of residential A/C when many compressors were not yet available single phase. Used to see a lot of this in south Florida in the '60s. Typically, the only load on the high leg was the A/C unit.

 

[Gary11734]

Used to be very common in the early days of residential A/C when many compressors were not yet available single phase. Used to see a lot of this in south Florida in the '60s. Typically, the only load on the high leg was the A/C unit.

There are so many condos built these days that I am positive that the motor is rated 208/240. All these multi-family places are 3 phase.

Rare to see a motor that is not rated 208-240... Do you know the brand? We can go check online the specifications...

 

[Gary11734]

I would suggest that the control board or transformer (if there is one) be checked to see if there is a 208v tap.


I have a customer with a high-leg delta service.

And, he doesn't have to worry about 208 volts!

Now that is something I have never seen. Is this an underground service, or do they have the big pot, little pot on the pole?

 

[MAC702]

I would suggest that the control board or transformer (if there is one) be checked to see if there is a 208v tap...

Very common on HVAC equipment. And I've serviced a lot of those on one roof that the installer never switched it. It was being fed 208V, and the tap on the control transformer was still the factory 240V setting, and it still had the big tag on it that said to switch it if feeding with 208V. They'd been working just fine for a couple years, but I switched them to the correct tap anyway.