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xtuner
Nov 7, 2005, 05:42 PM
OK, maybe not... I have done many 110V rewire jobs in this house, and hooked up a 220V outlet for an electric range. All simple and straight-forward stuff.

I just got a tankless electric water heater. It requires 220V. It has ONE hot wire coming out of it... Yup - just one. A black wire, a white (neutral), and bare (duh... ground ;o)

How in the &&^$?? Now - I'm no sparky, but if I'm not mistaken - you aren't supposed to splice 2 hot wires from different lugs, right? And if you splice 2 hot wires together from different breakers on the same lug, you lust double you amp draw capacity, right??

The water heater is made by Niagara Industries ( www.tanklesswaterheater.com ). What am I missing here? Thanks!!

Mike

tkrussell
Nov 7, 2005, 06:33 PM
I can understand your confusion, having learned the basics of electrical wiring. Manufacturers are not , however, obligated to wire their products according to electrical codes. So they may use a black and white wire for voltages other than 120 volt.

Only with 120 volt, does the white wire mean neutral, in building wiring. Since the manufacturer of your heater states to connect the unit to 220 volts, you are to connect 220 volts to the black and white on the unit.

I checked out their website, fairly useless, for your purpose. If you are wary of connecting the 220 volts to the black and white, give them a call. Their number is on the contact page.

I did note they do offer a 120 volt unit. Is it possible that's what you have? Most manufacturers do not want to confuse installers by using unconventional color codes, this may be one that does not care about that.

Exactly which model number do you have? I am curious about the KW size of your unit and the size wire you are using.

I also remember wiring many standard water heaters that are 240 volt, and finding black and white wire leads.

Now your question about the circuit breakers, and doubling to get double the capacity. I need a better explanation of what you are referring to before I answer.

xtuner
Nov 7, 2005, 08:24 PM
Thanks TK,

I actually called the electrician (long-time friend of a friend situation). I asked if it was possible that the white wire was the additional hot lead. He said it was possible, but if the unit was being marketed as residential, it should have a black stripe at the very least. So I posed the question to my truck forum (LOL!), and a resident electrician there told me that the white wire WAS the additional hot lead. So I tried it (he's never steered me wrong before). It works. I wrapped a piece of black electrical tape around that second lead - which is code, last I knew, here in Michigan.

The model number of my heater is the N-120. Every heater they offer is 220V, except their POU N-10.

As for what I was referring to with circuit breaker wiring...

I was taught that you NEVER cross a lead from one lug to the next. As in - you have a main service panel. That service panel has 2 power inputs (leads/lugs). Each is 110V, but on a different frequency. If you cross one lug to the other in parallel to try and obtain 220V, you will backfeed the panel and cause the main breaker to cycle itself off (pardon me if I'm not saying this right ;o) . If you take 2 separate breakers, say, each rated at 30A, and run them from the same lug to a final appliance, you'll still have 110V, but you'll have 2x30A of draw potential.

And yes, their website IS useless... They didn't even send me mounting brackets LOL!! I think the heater should suit my needs, but I'm kind of left spinning from the lack of QA and customer attention... I saw the number to call - wasn't ready to resort to that yet... If their website and lack of support accompanied with their product was any sign - I'm sure the phone call would have been close to hellish LOL!

Either way - the electrical side of the equation pans out now. Now to just get it plumbed and test the thing ;o)

Thanks!