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Using spring wound timer on one leg of 240V line thermostat?

Using spring wound timer on one leg of 240V line thermostat?


Old 03-06-19, 10:59 AM
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Using spring wound timer on one leg of 240V line thermostat?

ok, I searched a little and found thread titles I thought would help me but they ended up not. Where I am staying the internet is terrible (speedtest 495ms ping, .19Mbps) so I am done searching for now. I sign papers friday for a house I am going to remodel. simple question, can I wire a 120V spring wound timer on one leg of a 240V line thermostat? the one I am looking at is rated for 2500W resistive. should I put the timer between the thermostat and unit, or before the thermostat if it is doable? there will be some areas with 120V heater and then I know it would "work" but is there a reason not to? and again before the unit or before the thermostat?

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Old 03-06-19, 11:34 AM
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Yes you can, however this timer cannot be used as the code-required disconnect for the heater. You will also need to have some kind of two-pole disconnect like a switch, breaker or pull-out that breaks both hot legs. The thermostat can meet the requirement if it breaks both legs and has an "OFF" position. It doesn't matter if the timer is before or after the thermostat.
Old 03-06-19, 06:17 PM
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I'm not sure I'd agree with using a 120v timer to break a 240v line. A devices rating is based on maximum voltage thru or across it and it will have 240v across it when open...... even in only one leg of power.

I went back to look at the specs on springwound timers. Some were rated up to 277vAC.
Make sure the one you choose is rated for 240vAC or higher use.
Old 03-06-19, 06:42 PM
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The timer can be a single pole timer but it needs to be rated for 240 volts or higher. Follow IBpooks info for disconnect requirements.

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