Tankless on existing 30 amp double pole breaker?

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ericarlson

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I need to replace my water heater, hoping to go tankless. My current water heater is on a single 30 amp double pole breaker. I can't find a tankless that runs on my breaker that will run my home. I wouldn't be running much more than a shower and a facuet in central CA foothills. Do they exist, if so, what is the make and model? Or will I have to upgrade my electrical?
 
Rheem has an 8KW model that will probably be ok for a single bath.
The 11KW model might be ok as well - but I think it requires a 40AMP breaker.
I have small slngle element Amazon clone that serves the kitchen and 1 bath.
 
Putting some perspective on this for you, @ericarlson a typical standard electric tank style water heater will have a 240V, 30A circuit. Depending on a number of factors that may be wired from your service panel to the point of the tank with #10 or #8 3-wire.

A whole house electric model of a tankless (you said "run your home"), such as Rheem RTEX-36 (just one example) requires 4 x 40A breakers. It's 36 kW. So you need more wire, smaller gauge...and you need to ensure your panel and service can handle it.

You need to carefully look at the specs of those offered to see which might fulfill your needs, and then consult an electrician to determine your wiring needs.
 
smaller gauge
I know what you are saying, but actually you mean "larger gauge". The smaller the number on normal house wiring, the larger the wire is, and the more power (amperage) it can carry.

Like a 12-gauge shotgun shell is larger than a 20-gauge shotgun shell.
 
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I investigated replacing electric tank water heaters with tankless in a couple of all electric homes. My research indicated that it would require a significant upgrade in the electric wiring (and probably a new panel), as others have stated above. In addition, my research indicated there was little if any cost savings switching from tank to tankless electric. If you had natural gas or propane, it might make more economic sense. However, when switching from electric to gas, you run into additional issues with gas lines and venting.
 
I investigated replacing electric tank water heaters with tankless in a couple of all electric homes. My research indicated that it would require a significant upgrade in the electric wiring (and probably a new panel), as others have stated above. In addition, my research indicated there was little if any cost savings switching from tank to tankless electric. If you had natural gas or propane, it might make more economic sense. However, when switching from electric to gas, you run into additional issues with gas lines and venting.
When my father complained of his $800 oil bill, he asked me about adding a conventional electric hot water tank (see other thread about this with photo) in lieu of the in-burner coil on his oil burner. You see, every time you turn on the hot water the oil burner would fire...the original "tankless"!

I told him no problem, but to speed things up he should have an electrician wire for it. Turns out since he had a fuse box, no electrician would touch it without new drops from the poles, new meter box, new code mandated disconnect outside, new service panel. Would have been $4,500. So, yeah if you think plumbing is costly try electricity.

I figured out a way to safely do it, without all that extra stuff which I would not do. It's been in two years now, and the old fuse box has been in since the mid 1960s...BIG reduction in his oil bill. His town owns the electric company so rates are low. It was the smart thing to do.
 
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