[573335]

I am having the same problem. I have two 240v circuits coming into wall box and was hooked up to a double circuit thermostat, but one of the circuits stop working. I replaced thermostat with a double pole thermostat. It controls two heaters on one line and two heaters on the other line. The two heaters in the first set are 10’ and 4’. The other heater set are 6 ‘ each. I marked all the wires on the old setup so I can hook the new double pole thermostat the same way.

What is happening now the first set (living room) keeps getting hot and does not shuts off as the second set ( kitchen) heaters turns off. The heaters sets are in different rooms as noted.

Are double circuits thermostats the same as a double pole thermostat?

 

[573335]

Re: Problem w/ two 240v baseboard circuits on single double-pole switch.

Note: the two white wires on the bottom are wire nut together and the two white wires at the top are wired nut together.

 

[joed]

Moved from 10 year old thread to new thread.

 

[Fishbulb28]

Are double circuits thermostats the same as a double pole thermostat?

No, and that's the cause of your problem. A double pole thermostat switches only one set of lines as it controls the temperature. The other set remains on at all times until you manually set the thermostat to the off position.

A two circuit thermostat switches both sets of lines as it controls the temperature. This is what you want for your heater configuration.

 

[Oldmaster]

A double pole thermostat controls both poles. Never heard of a 2 circuit thermostat. A double pole thermostat functions like 2 single pole stats together. They are not internally connected and could control 2 circuits but then you would only control one phase of a 240 circuit and have no positive off as required by code.

 

[Fishbulb28]

A double pole thermostat controls both poles. Never heard of a 2 circuit thermostat. A double pole thermostat functions like 2 single pole stats together.

Attached you'll find an internal diagram of a typical double pole line voltage thermostat. Only one line is switched via the thermostatic control. The other switch remains closed until the thermostat is set to its off position, at which time both lines are switched open.

A two circuit thermostat does switch both lines via thermostatic control.

They are not internally connected and could control 2 circuits but then you would only control one phase of a 240 circuit and have no positive off as required by code.

While a disconnect is required, there is absolutely no requirement that a thermostat be that disconnect. Switching only one line of a 240V circuit is perfectly acceptable.

 

[Jim Port]

To qualify as the disconnect the thermostat must switch both legs. Leaving one leg energized is not acceptable.