[csperan69]

Removed Robert Shaw 190*thermostat w 4 screws 1 3 4 5.( 2+ 6 blank)
Bought camco 170* w 4 screws - 1 3 2 4
This is for single element 80Gal solar water heater.
Red wires to 1 + 2 and blk to 3+4?
Tester lites w above combos

Please advise

[massplumber2008]

Hi Csperan69:

We can't work off colors... wouldn't be safe... ok?

If this is a typical 220-240 volt single element then the middle picture below should help. Here, you have two-110 volt legs coming from the junction box down to the thermostats, usually one red and one black. One of these connects to #1 terminal and the other connects to the #3 terminal. The other two wires from the element connect as drawn (#2 and #4).

If this is a 110 volt single element then the right picture should help. You can see that the hot leg (black wire)connects to#1 and the two wires from the element connect as shown.

If these don't help or you have more questions pop over to the electrical forum and see what they have to say... ok?

MARK

[xtropx]

Can you run dual elements off a single element thermostat?

[massplumber2008]

Hi Xtropx

I'm betting we could figure something, but why the heck would you do that when you can simply purchase the correct thermostat for about $8.00??

Please explain why you would ask this question, OK?

Mark

[xtropx]

I was trying to just wire it up that way so I could forget it and move on with life. Hadn't had a shower in 3 days as the water heater problem cascaded into a completely new shower-stall install project.

More problems however: Bought completely new thermostats, and wired them up according to the provided diagram. The thermostats are still not shutting off when the HW heater reaches the requested temperature. It keeps heating until so much pressure builds that it bursts the safety release valve. Both Elements test at 13.5 ohms and I tested 240v at the top element with a multimeter. The bottom element never seems to get any voltage. What the heck is going on? I replaced the bottom element yesterday. Is there any way that the top element could be the problem and cause the thermostat to not shut off? It is the only piece I have not replaced. Thanks for the responses, this is driving me nuts.

[massplumber2008]

My only guess at this point is that you must have miswired something. Here, there are so many wires and different colors that it is really easy to mess up... ;)

Double check the wires from scratch. Heck, I'd even take it all apart and start over chasing each wire back to the junction box to be 100% sure, OK?

Finally, if all is wired properly then it is possible, however unlikely, that the new thermostat is defective or even the wrong thermostat for your heater... seen that, too!

Mark

[hkstroud]

This is for single element 80Gal solar water heater.

Does that mean that you have a solar water heater or does it mean you bought a thermostat for a solar water heater?

[massplumber2008]

Hey Harold

Xtropx jumped in on an old thread so the single element 80 gallon heater doesn't apply to him (applies to csperan69)... ;)

[hkstroud]

Thanks Mark
Sorry, getting old.

Tom,
Delete me.

Agree with you Mark that it must be wiring. Only other thing could be it is that the thermostats and over temperature sensor are not in proper contact with the surface of the tank. Perhaps that should be checked.