Or a high quality one designed for in-floor radiant heat, e.g. Tekmar 552. Very simple to set up, very few gimmicks, and pretty much just works. (The Tekmar s

Or a high quality one designed for in-floor radiant heat, e.g. Tekmar 552. Very simple to set up, very few gimmicks, and pretty much just works. (The Tekmar smart home interface for it is offensively priced. The thermostat works fine without it, though.)