Electric tankless water heater?

[Dirtebiker]

Anybody have experience with tankless electric water heaters?
Mom wants to put them in her double, mainly to make more room for furnace maintenance (very tight quarters).
We have a gas unit in one home but don’t know anyone with electric.
Looking for brand recommendations and what size works for you. The double is 2br, 1ba on each side so I’m thinking around
24-27kw should be big enough?

 

[bcannon]

I've put a couple in for friends and they really seem to like hem. Only thing you need to make sure of is if you have enough power to power it up. Last one I did IIRC took a 60amp 2pole and my buddy had to do a electrical upgrade to cover the power usage. He has said its saved him $30-$50 a month on his electric bill depending on the usage. He has wife and 2 girls so it definitely gets used.

 

[Dirtebiker]

Thanks bc, that is one question I have for electricians. There’s plenty of room in the box to add three double breakers but I’ve never come across a main breaker outside of the box. It’s in its own box next to the meter. It’s a 225a breaker so does that mean we have 200 amp service?

 

[bcannon]

Should mean you have a 225amp service but what feeds the panel and the size of panel is what you need to know. Thats the important part.

 

[Cameramonkey]

I looked at these. Was told that unless your breaker box is very close, its going to be expensive to run enough big copper to it.
Second, electrics are not that efficient as compared to gas units. It takes a LOT of energy to generate that many BTUs.
Third, due to our hard water, you'll need to really stay on top of descaling them or they will clog.

 

[Dirtebiker]

I looked at these. Was told that unless your breaker box is very close, its going to be expensive to run enough big copper to it.
Second, electrics are not that efficient as compared to gas units. It takes a LOT of energy to generate that many BTUs.
Third, due to our hard water, you'll need to really stay on top of descaling them or they will clog.

Breaker box is about 6-8’ from water heater.
the water in Beech Grove seems to be ok. At least there wasn’t any build up in the old water heater when we drained it.
they do that a LOT of power for sure. Depending on size of unit, they use either 2,3,or even 4 30, 40, or 50 amp breakers.

 

[schmart]

My experience was with one 40 years ago, that only had 1 40A circuit to it.. probably 7Kw. I KNOW that one wasn't big enough to provide for a satisfying shower...

The water heating calculator indicates that for 4 GPM, heating from 55 deg to 105 deg, you need almost 30KW. That is 90 amps total, which is a significant portion of a typical home service.

--Rick

 

[rkwhyte2]

We had one in my old house. Greatest thing ever. It was a 28k unit but that was with the elements the company provided. Once those go bad you just use the 5.5k elements I think. Here is the web site for the one we had. https://www.seisco.com/

I had to replace the entire thing after about 15 years. On a side note I'm pretty sure I could hear the electric meter spinning like a top when it was in use.

Forgot to add this was a 3 bedroom 3 bath house.

 

[DoggyDaddy]

I've thought about looking into one of these, but I think I'd rather go with gas. I know I have gas plumbed to my utility room from when we used to have a gas dryer, and my existing electric water heater is in there, but on the opposite wall from where the gas dryer was, so I don't know how expensive it would be to either reroute the gas or reroute the plumbing.

 

[Dirtebiker]

I've thought about looking into one of these, but I think I'd rather go with gas. I know I have gas plumbed to my utility room from when we used to have a gas dryer, and my existing electric water heater is in there, but on the opposite wall from where the gas dryer was, so I don't know how expensive it would be to either reroute the gas or reroute the plumbing.

Moving a gas line or water lines shouldn’t be too big a deal, I could do that for you.
I’m sure gas is more efficient than electric. We don’t have that option.

 

[Alamo]

My apartment in Germany had an electric tankless water heater for the bathroom, and that was back in the late 80s. It was the cats meow. I’ve always wanted one since. I don’t remember anything about the electric bill but it didn’t stand out to me. Hot showers Were Immediately hot and effectively endless.

I’m definitely gonna put one in my current house in the not too distant future.

 

[cburnworth]

You will def want a ball shutoff valve installed with the electric so water flow can be throttled a little if needed. Power is def a big issue with the tankless, our water temp in indiana requires the larger unit and if you only have a 100 amp breaker it is a no go.