Posted by Harold Kestenholz - Hydronic Network on October 30, 2001 at 13:06:21:
In Reply to: Recommended thermostats for hot water radiant heat posted by Julie on October 29, 2001 at 19:50:24:
Heat is just heat, but how it gets to the person counts mightily. Sending a breeze to the body at temperatures cooler than the skin makes discomfort. Surrounding the 91F skin temperature with warm radiant heat makes the difference. Air has no radiant heat, hot water heat radiation does.
Air systems whoosh air from registers over the body and the breeze reaches a thermostat quickly. Water reaches radiation, stores some heat in the walls and furniture and then reaches the thermostat, so there are differences in the length of each heating cycle.
Fortunately, thermostat manufacturers know this and include slide settings or switches to compensate for the cycling rate of the heating system. The way to set the thermostat for the type of heating system is explained in the instruction sheet that comes in the box with the thermostat.