[william sparky]

How to install 29 kw water heater

[tkrussell]

Did an installation manual come with the unit?

If the voltage is 240 volts single phase, the unit draws 120 amps. The wiring will be very specific for this. So the voltage and system is important.

More detail than your short question would be helpful.

[stanfortyman]

More detail than your short question would be helpful.

Agree.
The only answer to your question as worded is "Call an electrician."


Are you sure it is 29kW and not 2.9kW??
If it really is 29kW then the ONLY answer is Call an electrician!

[william sparky]

29 kw tankless water heater requiring three 50 amp. d.p. breakers to be installed in crawl space running from 400 amp. Splitter box.unit is not in sight of service.what material do I need?

[tkrussell]

Don't start a new thread for the same topic. Just Reply to the same thread as your original question.


I thought this would be the case, a tankless unit. I don't get these units, with a potential draw of 120 amps. That will make the meter spin.

So I guess I have to assume that this is located in a home.

Is the wiring method in the home currently Romex cable?

What is a 400 splitter box?

[stanfortyman]

3- 2p50 breakers
3- 60A disconnects
12- 3/4" NM connectors
And a LOT of 6/2NM cable

Seriously, do have any idea of what you are doing? What is your level of experience?

[william sparky]

I am a residential electrician but have not installed such a large unit before.the wiring method is romex.we are not allowed to use self contained meter boxes here for 400 amp.we run our service conductors to a disconnect, then to a c.t. cabinet, and then to a splitter box.then we run two 200 amp panels from the splitter

[stanfortyman]

i am a residential electrician but have not installed such a large unit before

Don't you think some of this information would have helped right from the start rather than asking your question the cryptic way you originally did?
See what we mean?
I would assume you are still an apprentice?


HOW do you plan to come from the "splitter" box? Is this a 400A MDP (main distribution panel)? Are there six open breaker spaces in it?

[tkrussell]

Since we have learned you are an electrician, I will speak to you as one.

This unit falls under the NEC 2008 Article 422 Appliances and is referred to in Section 422.11 (F) 3. limiting the unit to the 120 amp.

This "large unit' is nothing more than three 50 amp circuits. Imagine wiring 3 ranges, etc.

Each circuit needs OCPD, feeder cable, service disconnecting means for each circuit at the unit.

Stan listed the basic materials list to do what I just stated above.

I have no idea why you mentioned a "splitter unit" You know very well that is for distributing 400 amp feeder into two loadcenters containing the branch circuit breakers, and the three 50 amp circuits need to begin at that point. The description of the service entrance equipment is irrelevant.

Hence, Stans question "Are there six open breaker spaces in it?".

What have we missed? Any other questions?