Hi all,

We recently moved into a new house with non working baseboard heaters on the third floor. I'd like to replace these heaters. Unfortunately, the breaker box is not accurately marked, and has lots of half sized (mini?) breakers in it. The only breakers with bars connecting them (like you generally see on a 240 circuit) do not power the heaters. The heaters are wired for 240 and the circuits are definitely hot right now.

How can I find the breakers that are responsible for these heaters? I'm getting tired of running up and down the steps to flip a breaker and then run back up to check my VOM. BTW, I'm checking for voltage by checking the voltage on the black/ground and white/ground combinations.

Is there a way to safely just short the circuit out so that the breaker blows? Or is there another better method?

Thanks for any and all help.

Jack

If this were a 120 Volt circuit -- you could take a corded radio and plug it

Into the circuit and turn volume up so you could hear it at the panel---

Then turn off breakers until the radio is off -- you can also start with all

Breakers off and see which one powers the radio... With a 2 cell phones

And a reliable helper you can probably locate the right circuits -- you

Check voltage while some one turns off breakers... Yeah for cell phones

What voltage do you get between the two hot wires? It's possible that the heaters are fine and they just wired a 120 volt circuit to both hots (or they're being fed off different single pole breakers on the same pole). If they're on the same poles, you'll get 0 volts between them and 120 between each of them and ground. If they're on different poles, you'll get 240 volts between them (which would make the heater at least part of the problem).

What voltage do you get between the two hot wires? It's possible that the heaters are fine and they just wired a 120 volt circuit to both hots (or they're being fed off different single pole breakers on the same pole). If they're on the same poles, you'll get 0 volts between them and 120 between each of them and ground. If they're on different poles, you'll get 240 volts between them (which would make the heater at least part of the problem).

I'm pretty sure that's what I get. I think that I measured across what I thought were the hot leads and got nothing, but measured each lead with the ground and got 120v.

Even if they are wired wrong, I still need to find the right breakers in order to replace the heaters or add a new thermostat. Is it safe to just short the hot and ground with a pair of insulated pliers and trip the associated breaker?

If they are wired incorrectly, is that from the breaker panel side? How would I correct that?

Thanks for your help.

Jack

If you aren't getting 240 volts between any of the wires, then it is 120 volts, unless a wire is open.
Haven't had to short to ground for years due to tracers and locators.
Don't know if it is considered safe or even common any more.
If I HAD to do it. I would grab wire with pliers(Insulated) and touch to back of box, needs to be metal. Don't get between the short, don't destroy your pliers. Short quickly.
If there is any kind of indicator, have some one stand there, while you switch breakers.
If you really wanted to be safe, turn power off to House. Then Work.

Might I suggest that you get a simple tone generator and connect it to one leg of the hot leads. Connect the other side to Neutral. A voltage test should yield 120 VAC. Turn the generator on and take the probe downstairs to the panel and then let the probe find the Circuit Breaker for you. Turn the breaker off, <still tone = No> you found the breaker!

What voltage do you get between the two hot wires? It's possible that the heaters are fine and they just wired a 120 volt circuit to both hots (or they're being fed off different single pole breakers on the same pole). If they're on the same poles, you'll get 0 volts between them and 120 between each of them and ground.

If this is one of the problems I have, could you elaborate on how to correct it?

I say one of the problems because I know that I want to change this installation to have the two four foot heaters run from the same programmable thermostat. Right now the two heaters are wired in parallel with their own built in thermostats.

But first I've got to get the breakers identified and turned off, and make certain that I do indeed have 240 up to the third floor.

Thanks!

Bump

Jack,

"Bump?" Is that supposed to mean something?

This type of question is not as simple as it looks. What you are actually measuring is the difference of potential between the two points. For example, if you are measuring the two wires bringing the feed into the heater, then you are looking at a combined 240 VAC difference between pole 1 and pole 2.

However, if you measure pole 1 against neutral or ground then you should see 120 VAC.

I can almost guarantee you that the trickle voltage to the thermostat is trivial when compared to the 240 volt needed to operate the heaters.

First are you certain that these heaters use 240 VAC? Would you send any technical information you can onto me here on the heaters?

Your goal is to have one thermostat, signal on and off operation to the four units, correct? What model have you chosen as the controlling thermostat or do you want to just use one of the "heater thermos?"

Bump means, he hasn't gotten an answer to his thread soon enough so he's pushing it to the top of the page. Considered to be very rude on these forums.

I wouldn't short to ground. There's always the possibility, however remote, that they're not wired properly to a proper breaker. Don't want to risk tripping the main that's too big of a short.

It sounds like they're wired for 120 and not 240 which may be why they are not working. Can you trace the wires at all?

Sometimes it's easier to shut all the breakers off and turn them back on one at a time. I would do this with a light bulb wired to the appropriate hot lead, easier than looking at a voltage tester. You can have one person at the breaker box and another person at the heaters. Remember to unplug all computers and electronic devices first.

Sorry about the bump folks; on other forums questions scroll down and folks tend to only look at the top few, so an older question may never get answered. I won't do it again; didn't mean to be rude, and I do very much appreciate all the expertise and answers already given.

Donf, if I measure between the two 'hot' leads into the heater, shouldn't I see 240v AC? The VOM bumps up a bit, maybe a few volts, but not much.

As far as the thermostat goes, right now each heater has its own built in thermostat, but I'd like to replace these with a single programmable one like the Honeywell RLV430A.

Bumping is accepted on some forums, not on others. Usually if I want to do it, I find something relevant to add so it's not obvious.

I agree you should be seeing 240 across the hot legs, that's why I think something is wired wrong.