A homeowner tells his installer that he wants a geothermal heat pump as well as a mod/con boiler to supply the radiant floor heating in his new home. The installer assembles the six-zone system shown to the right.
Once the system was put in operation, the owner began complaining that some rooms were too warm and that there were wide variations in floor surface temperature within a given room. He also mentioned that the heat pump seemed to turn on and off rapidly.