hmm.. those are pretty high loads, but that is one thick slab if you aren't insulating between them.

Don't set the polaris back; at lower water temperatures their condensation will actually drip onto your igniter and cause frequent burn outs. They have to be run at 140+.

I think a Tekmar 512 thermostat with slab min/max settings and two stage w/baseboard might be the good cheaper match, wouldn't be too pricey... though we would usually use an indoor feedback/outdoor reset controller for the radiant and be done with it, Say a tekmar 362 or something like that. That means adding a $500+ controller, but that feedback combo can work miracles.

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Northeast Radiant Technology, LLC
-=RFH Design, Supply and Consultation=-
RPA certified Radiant Designer
http://www.NRTradiant.com
rob@NRTradiant.com

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