I have a customer that has 3 heating mats under the tile. This was installed a while back and a relay was used. I measured a 21 amp draw for all 3 mats. I installed a new thermostat that is wifi enabled and it worked well for a while. However I am now throwing a code that says that the current draw is to low. The coil is a 30amp 240v with a 120v coil. The issue is that the thermostat will not see the current draw of the relay coil. The thermostat needs to see a draw of at least 0.3a. Does anyone out there know of a relay that will have a coil relay of at least that, if not a little more? I would like to find a single phase 2 pole 240v with 120v coil that draws 0.4 to 0.5a
 
You won't find a relay with an intentionally higher coil current.

Your best bet would probably be to connect a small dummy load in parallel with the coil.
 
have you looked at the instructions for the thermostat?
i am wondering if it is only suitable for direct connection to the load as it uses current monitoring as part of its feedback loop.
 
Yes I have talked to the people at MySa thermostats and you both are correct. They told me that this thermostat was not designed to be used with a relay. They ran all the wiring to a relay in a crawl space. And they ran 10ga 30amp romex to the relay. From the relay coil to the thermostat they ran 14ga wire. Not nearly enough to carry 21 amps. But the work around that they gave me was to take one of the heat mats (7amp's) and run it through the thermostat therefor giving it a load and let the other 14amp's continue through the relay. Sounds like a good idea I will try that when I go back to his house.
 
Yes I have talked to the people at MySa thermostats and you both are correct. They told me that this thermostat was not designed to be used with a relay. They ran all the wiring to a relay in a crawl space. And they ran 10ga 30amp romex to the relay. From the relay coil to the thermostat they ran 14ga wire. Not nearly enough to carry 21 amps. But the work around that they gave me was to take one of the heat mats (7amp's) and run it through the thermostat therefor giving it a load and let the other 14amp's continue through the relay. Sounds like a good idea I will try that when I go back to his house.
That's what I was going to suggest.
 

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Need relay advice for in floor heating
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Electric Underfloor Heating Wiring
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Fireman0750,
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