I wouldn't of bought the mat stat bc it's on/off meaning it will drop a couple degrees then turn on and reach temp and shut off and then drop a couple degrees and turn on then reach temp and will continue to do that. Your other thermostat was better bc it's pulse proportional and will keep one steady temp. I would try the new heat mat with your old thermostat and if it works good I would send back the mat stat or keep it as back up.

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