Wiring to a water heater

bvsmith_1974 · 09-02-2008, 08:02 AM

Hey all!

Ok, apparently I have some funky setup, because I'm not quite sure what I've done here. I had to replace my old water heater because it was on the verge of a rupture. I got a new Whirlpool lowboy 38 gallon. When I went to hook up the wiring, I saw that there were two sections of wire run to this water heater: One coming from the breaker box (connected to a 30 amp double pole breaker with a single switch) with a black and a white wire, and then another, which is running to what is apparently my heat pump outside, because now I'm not getting cold air into the house. This other wire had one black, one white, and one pink ( or could be red, it's faded). When I test the power to the lines, I'm getting 240v through the lines coming from the breaker box. The way they were originally connected was that the white from the breaker box was connected to the pink going to the heat pump, and the white in the wire going to the heat pump was hooked to the red going into the water heater. The black from the water heater and the two blacks from the both wires were all hooked together, and then there was the wire connected to the ground screw.

When I hooked it back up that way to the new water heater, I was only getting 120v to it (but the air was working). I rewired it so that the 2 whites, the pink, and the red were all hooked together, and the blacks were all hooked together. When I did that, I burned up both elements in the water heater.

Any suggestions on how this should be hooked up? Thank you!

Edit: One thing I should have added, the water heater is a 240v.

HouseHelper · 09-02-2008, 09:34 AM

Wire it up just like the old one was wired. The R/W/B wires most likely go to a load control device operated by your utility. It will control only one leg of the 240V circuit, so reading 120V to ground on one leg would be correct.

bvsmith_1974 · 09-02-2008, 09:42 AM

My problem when I did that (assuming I got the wiring right) is that I was only getting 120v to the water heater instead of 240v. Did I have something wrong in there? Here's how I had it when I wasn't getting hot water and only 120v (but was getting air):

White from breaker box hooked to red from load control box.
White from load control box hooked to red of the water heater.
Black from both load control box and breaker box hooked to black in water heater.
Ground wire to ground screw.

As an aside, at one point as I was trying to make things work, I hooked both whites to red of the water heater, both blacks to the black, and left the other red from the wire out of the mix, and turned back on the breaker. When I did this, the heat pump outside started making a "choking" noise, for lack of a better term.

frenchelectrican · 09-03-2008, 04:32 AM

I can't be too sure but let me run thru my hunch on this one senice you say you have meter controlled switch for water heater and heat pump ?

If so then you have one relay a DPDT or DPST depending on the POCO set up the relay.

so let say WH1 and WH2 is waterheater circuit #1 and #2 's

HP1 and HP2 that is for heat pump

I will describe a very crude diagram here { I hope Stubbie can make a drawing as i will explain along the way }

Ok you have WH1,WH2 from one double pole breaker and HP1 HP2 from other double pole breaker.,

Ok got it so far?

Now let go down the " path " to the relay box .,
The WH1 and WH2 will be in the relay box as HP1 HP2 will be there as well.
{ It willbe a wise time to mark each circuit so you dont get this mix up you will see why a little bit }

Now the HW1 will bypass the relay connection it will go direct to the waterheater.
Just hold on a min before you fly out of the chair here.,,
The HP1 will bypass the relay and it will go driect to the HP disconnect switch.
Ok Now here the tricky part

.,

The relay is there and you will see two concats let say C1A and C1B for one side while other side will call C2A and C2B

The second lead { WH2} from the breaker will land at C1A then outgoing wire from C1B will go to the waterheater while the HP2 from the breaker will arrive at C2A then the C2B will go to the heatpump disconnect switch

the function of relay is to inturpet the power when the POCO meter signal trip the relay to open them { off } or close them { on } depending on the time of day and hours.

Normally this what the common way to wired but if not the same way let us know I am sure there is other route as well due I know at least 2 most common way with the Peaking relay.

Oh yeah the last thing about waterheater make sure you get the tank filled up with water first before you turn on the power otherwise you will burn up the element.

Hope this will help ya with some info.

Merci,Marc