wiring for electric water heater

[Ken]

Hi,

This is a noob question and I wonder if there's any qualified wireman around to answer my question. I have just fixed up a water heater but because there was no existing power points in the bathroom, the wireman fixed one up which was extended from the power socket in my room. It was a bit of a hassle to take the power from the main because a lot of drilling has to be done and this is just a rented place. I figure I could live with that. Only thing is that he asked me not to use the air-cond together with the heater at the same time. The water heater also has built in ELCB. Now my question is whether are there any dangers involved with the current scenario? My father is a bit paranoid because he asked for a second opinion from a qualified wireman and he said he knew of a couple who was electrocuted recently because the heater switch was not taken from the main point. I hope I can get an opinion from this newsgroup. I apologize if I'm not clear enough as I don't really know the proper terms to use. Thanks in advance.

Ken

[Joseph Meehan]

That story is likely a misinterpretation of the facts. Properly wired there would be no difference is safety either way.

Personally I would not have allowed it done that way. I would have paid the difference and had it done right by putting in a dedicated circuit.

I have not checked, but I would not be surprised to find out that code requires it to be on a dedicated circuit. You might check the instructions that came with the heater. In any case I believe it is at best sloppy work. The dead giveaway was "he asked me not to use the air-cond together with the heater at the same time."

[RBM]

It sounds like a small heater and probably uses the same amperage and voltage that the air uses. Clearly if both were used at the same time it would overload the circuit and should trip the breaker. What he should have done to make it safe, is install a single pole double throw switch (assuming it's 120 volt) in the circuit which would allow current to ONLY go to either the airconditioner or the heater at one time.

[Speedy Jim]

Sounds like you ought to post to this group:

UK.D-I-Y

Jim

[Ken]

Thanks for the replies.....the heater that i'm using is a Pensonic PWH767E. The power rating on the box says 3.6Kw 15A, 240 a.c.

50Hz....not sure if the info helps....I don't know if it's a small or big heater. Anyway the problem isn't with the air-cond, I never and don't plan to use the air-cond. That socket is purely meant for the water heater and also my desktop computer. I'm also willing to turn off my computer while the heater is on. So would that have any risk and danger of electrocution? The water heater also comes with built-in ELCB. Wouldn't the most that would happen be that the main switch be tripped and besides that....there's also ELCB protection. How dangerous is the electrocution part?

I'm just wondering if my father is being worried for no reason. I do plan to have it fixed to the main power later but only when I'm free. So for now should I stop using it because of this concern?

[trader4]

The electrocution risk has nothing to do with it being on a shared circuit with the air conditioner. Electrocution risk comes if it is miswired, has a reversed hot, neutral, ground, etc. However, this is a pretty dumb way to wire this up. Who wants to figure out when to heat water, vs when to turn on the air conditioner, etc? He should have been able to put this on either it's own circuit or another circuit without a large load like the AC. If you can live with the incovenience and it is otherwise done correctly, there is no elecrocution risk different from any other outlet.

[Ken]

Thanks for the reply......i've uploaded some pics to give a better idea. He stated that it takes a lot of work to connect to the main...maybe have to go through the roof and all the way downstairs. I'm staying in a double-storey terrace house. So he said it's easier to get it from my room which has the attached bathroom. What bout the story about the electrocuted couple that I heard from my father. They've also done the same thing......dragged from the room socket. So it's basically miswired for that case?

this is the socket in my room where it's being extended from

this is the water heater switch in the bathroom and this is the water heater

[trader4]

Well, it sure looks like hell. For me to have had it done that way I would have to have been convinced that it was going to cost a lot more to put it on it's own circuit with most of the wiring hidden, instead of running it like that. But once again, that has zippo to do with it being an electrocution risk. Personally, I wouldn't want an electric heater in my shower regardless of how it was wired. I don't see a GFCI anywhere. Did he put in a GFCI breaker in the panel? What country are you in? I would think it would be a code requirement to have a GFCI. I would definitely make sure there is a GFCI, as that is key to avoid your electrocution scenario.

[RBM]

Not the prettiest job I've seen either, I think it would have made more sense for him to have put a plug on the end of the cable so you could disconnect it at will

[mm]

Then you don't have to worry about that, but you should be sure to leave a detailed notation for the landlord and for the next tenant too when you move out. They'll probably figure it out that you can't run both at once, but they should know that that's the way it was intended.

How big are the circuit breakers in your house, for this circuit and for the others? 15A? 20?

Don't pour hot water on your computer. (or cold water)

[Don Young]

That heater looks to be located over the bathtub. If so, it may be a severe electrocution hazard unless fed from a properly installed and tested GFCI switch. It looks like the switch may be a GFCI type, but proper installation and testing is critical. Don Young

[Chris Lewis]

According to Don Young :

I don't think the switch is GFCI. Just UK-standard outlet switching.

UK wiring standards are very much different than ours with different voltages than we're used to (almost everything is 240V) and various other unfamiliar things like "ring mains" and rather different appliances.

I very much doubt that there are _any_ demand heaters that are appropriately certified for installation _inside_ a shower enclosure in North America - even with GFCI.

I would _hope_ this device is rated for this location - it may well have a builtin GFCI.

If the instruction sheets or labeling on the device is accessible, I suggest doing some research as to whether the device is appropriately rated for this location.

In North America, demand heaters are usually tucked out of the way inside enclosures. Eg: under the sink in a vanity, in a service room (eg: basement) or wall unit with a door or a closet.