Electric Baseboard not working

[ebuck]

I have a question about a baseboard not working anymore. My tenant broke the cover of the existing thermostat (wall mounted) , the thermostat is a low voltage one (small gauge wires , 2 of them). The low voltage thermostat connects to the baseboard it has a built in circuit board, it gets activated by the low voltage thermostat. The tenant replaced the low voltage thermostats with a line single pole Voltage one , so he connected the two small wires to it.
This is not correct, but wouldn't this still work ? or is there some resistance inside the Line Voltage thermostat that would prevent the small amount of current to pass through,(heat set to max to make sure ) ? I then asked the tenant to take the wires as they are (connected to line Thermostat) together, this should bypass the thermostat and close the circuit. I didn't tell him to disconnect the wires from the thermostat ,. just connect them together.
I figured this would bypass the thermostat but the heater still doesn't come on. Will it make a different if I asked him to disconnect the wires from the thermostat and just connect them together ?

The breaker is fine and the voltage to the heater is good.

* Edit, would like to add that the original thermostat was thrown out.
* My tenant is not around to test.

 

[DAKSY]

Test the low voltage wires for continuity. If they're compromised, no signal is getting to the heater.

 

[ebuck]

ok I'll test but one question, .. If I just connect the two wires from the thermostat together the heater should work provided there are no other issues ? Is there any magic in those low voltage thermostats ? or just a simple close/open switch ?

 

[DAKSY]

It is just a switch.

 

[Bad LP]

ok I'll test but one question, .. If I just connect the two wires from the thermostat together the heater should work provided there are no other issues ? Is there any magic in those low voltage thermostats ? or just a simple close/open switch ?

The only magic in the wires is smoke. Don’t let the smoke out of the wires.

 

[zrock]

just go buy the proper thermostat they are cheap and easy to install instead of trying to make things work ... Why are you getting your tenant to mess around with this? your just looking for a law suite if something goes wrong

 

[ebuck]

Its low voltage , no risk of fire or shock but yes I shouldn't let him do it. I'm trying to debug the issue not just trying to make it work, before I call an electrician in.

 

[gthomas785]

Have you tried jumping out the thermostat terminals at the heater yet? That will tell you if it's the heater or something in the thermostat wiring.

 

[ebuck]

Have you tried jumping out the thermostat terminals at the heater yet? That will tell you if it's the heater or something in the thermostat wiring.

I'm going to go down and install a LV thermostat and if that doesn't work I'm calling an electrician. I could change the heater myself and use a built in thermostat right on it. The wiring for that is very easy. But it's a condo and if anything goes wrong even if the heater malfunctions and there is a firer then I may be on the hook whether done right or not. I imagine a couple hundred for labour and $100 for heater .. and avoid any hassles.

 

[ebuck]

Alright so I bought a typical thermostat hooked it up and switched it on and still no heat.
Then I took my meter out was curious , should have done this before if I would have paid attention to the red and black striped wires took
a reading on the two wires and I saw 16v .. WTF. The other wire is ground attached to the box.
So basically when the thermostat kicks off it shorts the connection, I'm baffled have no idea how this ever worked .
To be clear the two low voltage wires coming out of the wall which were used in the old thermostat has 16v across them , it should be 0.

The metal grill above the wired on the heater below appears to be a heatsink and behind that is some electronic, I didn't fully open it but took a peak behind it. I assume that is what the thermostat connects to and the circuit probably sends the 16v across the wires to the thermostats. So either some special thermostat was used or by shorting the wired with the LINE thermostats damaged the circuit in some way. I doubt it though but I'm at a loss to explain.

My next option is to replace it with a NORMAL/STANDARD heater with built in thermo.
I just emailed customer support, probably calling them tomorrow see if they can shed some light.


The baseboad heater is 208V Chromalox Model BL-LVER got some number on the side I the side LR 56555 (240V) 10.4ANI 60Hz

 

[gthomas785]

There should be voltage on the thermostat wires. Otherwise how would the thermostat do anything

 

[ebuck]

If you have a positive on one side of the switch (thermostat) and a negative on the other side of it and you close the switch you get a short.
Unless there is a load between them.

 

[gthomas785]

If you have a positive on one side of the switch (thermostat) and a negative on the other side of it and you close the switch you get a short.
Unless there is a load between them.

Ever measured the voltage between two terminals of a light switch while it was off? surprise, it's 120 volts. That doesn't mean you'll create a short by turning on the switch.

There is a load between the two wires, in your case it's the contactor that turns on the heat. Normal thermostat operation. You connect the red to the white which supplies 24V I guess 16V to the white wire and closes the contactor.

 

[ebuck]

Oh, then I clearly don't understand how a thermostat works.
I thought the two wires should be L1 and the other LOAD and when thermostat triggers it closes that connection .

 

[gthomas785]

Oh, then I clearly don't understand how a thermostat works.
I thought the two wires should be L1 and the other LOAD and when thermostat triggers it closes that connection .

No, you're pretty close, that is how a thermostat works. you are just making the incorrect assumption that connecting two wires at different voltages will cause a short.

In all cases when you connect two wires at different voltages it will cause current to flow through the wires, but the amount of current depends on the total series resistance of the circuit. it is not dangerous to connect the two thermostat wires together because they are current limited by the other components.

The diagram you showed is for a "line voltage" thermostat which connects directly to the load - the full heater current flows through the thermostat. A low voltage thermostat is a similar idea, but instead of having to handle the full heater current it just carries enough to energize a relay (contactor) which in turn energizes the heater.

 

[ebuck]

Similar to this except the thermostat would have one side to + and the other to - .. Okay that's where my confusion came in .. I didn't take into account the load aspect of the relay or see it visually like this.
Also, I assume that the power to the switch is coming from the heaters circuitry somewhere or there is a transformer at the panel but I don't see any indication of this.

 

[NorMi]

You already connected the wires together coming out of the wall at the thermostat location and nothing happened, this tells you right away the thermostat isn't the (only) problem. Connect the thermostat wiring together in the same fashion at the heater, bypassing the wiring in the wall to the thermostat - if it still doesn't come on, the problem is probably the heater/control board.

 

[ebuck]

I just find it strange, my old tenants moved out in May, thermostat cover broken , replaced , new tenants moved in, thermostat not turned on until now and heater is not working. Called my previous tenants and they said no issues with it unless they are not being truthful.
So my focus was on the thermostat being the issue.

Note to self, check heaters before tenants move out.

I have no time left to investigate further , curious though but I need to get the heat back on before it starts to get cold here, it's been 5 days already without heat. Getting Electrician to replace the heater.

Thank you everyone for your help.

 

[Poconojoe]

You already connected the wires together coming out of the wall at the thermostat location and nothing happened, this tells you right away the thermostat isn't the (only) problem. Connect the thermostat wiring together in the same fashion at the heater, bypassing the wiring in the wall to the thermostat - if it still doesn't come on, the problem is probably the heater/control board.

This is good advice.

 

[ebuck]

Ya it is a good suggestion.

 

[vc9090]

I came across this post. I know it's been awhile but I was wondering if you (ebuck) figured out what was wrong. I have a similar electric baseboard heater that is controlled by a low voltage thermostat.

I wanted to swap it out and for a wifi enabled thermostat (Honeywell RTH6580WF). I thought it would work since it's a low voltage thermostat, but when I installed it, the baseboard didn't heat up. I reinstalled the old thermostat and it still didn't work. I tested the voltage in the low voltage lines and it's reading no voltage. I tested the high voltage lines going to the baseboard and there's power. My baseboard looks similar to yours. I'm assuming there's some sort of transformer within the baseboard but as i was searching online, I came across your thread. Anyone familiar with Chromalox baseboards?

 

[zrock]

it says right in the description on honeywells site not computable with electric baseboard.

 

[vc9090]

My electric base board has a 24v relay on the baseboard that is controlled by a low voltage thermostat (as per the pictures)? I understood that the Honeywell thermostat doesn't work with High Voltage lines. I've not done it before and i could be wrong, but I researched a bunch on the Internet (...and the Internet is never wrong...jk). Having said all this, it does require an additional 24v wire as a C wire, which i had done with a separate plug-in-the-wall transformer.

Regardless, the electric baseboard doesn't work even with the old low voltage thermostat. I'm going to open up the baseboard further to investigate. I suspect the relay/transformer that's build into the electric base board is fried or something. Might have to end up getting a new baseboard.

 

[gthomas785]

My electric base board has a 24v relay on the baseboard that is controlled by a low voltage thermostat (as per the pictures)? I understood that the Honeywell thermostat doesn't work with High Voltage lines. I've not done it before and i could be wrong, but I researched a bunch on the Internet (...and the Internet is never wrong...jk). Having said all this, it does require an additional 24v wire as a C wire, which i had done with a separate plug-in-the-wall transformer.

Regardless, the electric baseboard doesn't work even with the old low voltage thermostat. I'm going to open up the baseboard further to investigate. I suspect the relay/transformer that's build into the electric base board is fried or something. Might have to end up getting a new baseboard.

I'd say you've got the right idea. If you don't have 24V at the thermostat, check voltage at the transformer. There could also possibly be a fuse blown somewhere in there. If all that checks out, it means your thermostat wiring is broken somewhere in the wall.

Ultimately the Honeywell digital thermostats still function like an analog thermostat, basically a set of dry contacts. When honeywell says they don't work on electric baseboards they mean line voltage. Any 24V switched system should work fine, although you do need the common which is basically a neutral wire to bring power to the thermostat.

 

[joop]

marette the two reds together and attach black to thermostat