I have a tankless hotwater heater that says it draws 54 amps (220 volts) but doesn't tell me the size of the circuit breaker to use. It uses #6 wire and I would think I would use a 60 amp dual breaker (30 amps on each breaker) to protect the wire. Is this correct or is #6 wire overkill? Any information would help.....
You already have the heater?? No install manual?
Who is the mfr? Do they have a web site? Most mfr list the breaker size for each model. Post the model #.
If the rating really is 54 Amp, you may need a 70 Amp breaker (that's 70 each side, NOT 35)
Is your electric service big enough to add that load?
Jim
Jim,
Thanks for the quick response. I am installing it in a small cabin I own and it has 100amp service. The model is a Niagara Titan SCR2 N120. The site is below but isn't much help. It's not a big deal if it doesn't work out for me but I'd like to try.
Chuck...
Speedy Jim wrote:
You weren't kidding about their web site :-)
There are a lot of highly technical factors here which you may be willing to overlook since it's a remote cabin. I imagine others will be along shortly to expand on this.
Back at the web site, their rating is based on 220V service, not 240V. The cabin likely has nominal 240V which would bump the load up to 59 Amp. A 60 Amp breaker (2 60 Amp poles, not 30/30) won't like that. I bet you will be looking at a 70 Amp breaker and even there it's a tad undersized. Check that the panel will accept large breakers.
Don't forget a Ground wire to the heater (bare ground, not White Neutral.)
Best luck at the cabin...
Not really. Try the FAQ. Always a good general practice, besides RTFM.
They covered your situation, so you might be less judgemental.
JJ,
Are you seeing something I am not in the FAQ? I did RTFM and it doesn't tell me what I need. Perhaps you are the one who should be less judgemental. Do you own stock or something in this company. Geez, lighten up.
Chuck....
snipped-for-privacy@sme-> > Jim,
You might want to check with the manufacturer for their recommendations. As I see it, assuming you have 240v, you need #4 wire and a 70a breaker. And you better not be using an electric oven while this is on!
The SCR2 N-120 draws a "maximum" of 54 amps. Meaning, it will consume a maximum of 54 amps at peak power output, only as necessary. Most local codes would call for the use of a 60 amp breaker, and a #6 AWG wire gauge. Your local code or installation could be different.
Jolt,
Thanks for the info. So that means I need a double breaker with 60 amps on each breaker? I have new Cutler-Hammer 100amp panel.
Chuck.....
jolt wrote:
Correct a 60 amp 220 breaker. I'm surprised that the rating plate doesn't specify a MAX breaker size.
True if his installation was 350' away so he gets adequate voltage drop from
240v to 220v. I would try to prevent that by using #4.
Here's what I found on the mfg's website....
It tells you what you're asking for. Matter of fact, a little later in this thread you thank another poster for a 'cut n paste' from the FAQ. see number nine in the following:
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.