[Sampon301]

I have a 460v 3 phase water heater I need to replace, I want to go back with a 208v 1 phase. The question is, Are there any drawbacks as far as utility cost to operate the 208v 1 phase vs the 460v 3 phase?

[stanfortyman]

No, just the recovery rate is likely less with the 208V unit.

You pay for wattage so check to see what the wattage is between the units.

If I may ask, why would you bother to run a new circuit for the 208V unit when you already have the wiring in place for the 460V?

[Sampon301]

No, just the recovery rate is likely less with the 208V unit.

You pay for wattage so check to see what the wattage is between the units.




If I may ask, why would you bother to run a new circuit for the 208V unit when you already have the wiring in place for the 460V?

The cost of the 3 phase water heaters is really expensive, thousands vs hundreds. We no longer need a heater the size of the old one and the heater is close to the electrical panel, so the cost of running a new circuit is minimal. This is in a 4 story office building and only serves the restrooms (8) for hand washing, there is also a recirculating pump we will continue to use. The old one is 18 kw and I would think the new one would be less than that, probably quite a bit. I know we are billed by kw usage but in a brief conversation with my electrician, he mentioned the 208v may be less efficient but he may have been referring to recovery time. Thanks for your response.

[stanfortyman]

Well then your idea makes a huge amount of sense. And you are right, a new smaller unit will likely be only 6000/4500/3380 watts, as opposed to 18,000(!! ).