Install 2-pole thermostat to 4-pole baseboard wiring

Old 09-11-16, 08:30 PM
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Install 2-pole thermostat to 4-pole baseboard wiring

I've seen several posts on 4-pole to 2-pole thermostat installation but have a few specific questions. We've just installed a Honeywell RLV4305 to replace a 4-pole thermostat by connecting the two white wires together (capped and taped) and connecting the two black wires to the unit, which is functioning properly.

In looking over the instructions again, they appear to me to require a fuse at the white connection by showing a sideways S symbol. Is this correct? If so, how is this done?

Beyond that, is there a way to be certain the thermostat meets requirements of the baseboard unit, which has no labels? I assume amperage is not an issue as the total baseboard is about 6' but how can I calculate amps without a label?

Finally, how can I tell if this meets code?
Old 09-11-16, 09:31 PM
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That symbol is not of a fuse..... it is the AC supply.... line.

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There should be an ID tag somewhere inside the heater. A typical 6' 240v baseboard heater would be 1500 watts.

Otherwise you would need an Amprobe (current meter) to measure the amount of current used.

That thermostat wiring is ok. The one major problem is that when it is shut off.... the heat no longer works but still has power to it..... one half of the 240v supply. This requires the breaker to be shut off before servicing the heater.

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