A couple years back there was discussion here about those heat exchanger fans, as I complain about our noisy ones too. As I recall, there are other units, from the same mfr. that you can buy to replace the factory ones, and are quieter. I just never got around to spending the money and doing the job. Perhaps someone here remembers details about the prior thread.
Similar to Ed's technique, we turn on the zone in the bedroom, or the heat pump in there, when we are in the living area, then vice versa at night. The electric element on the HydroHot is adequate overnight. We also use a small box electric heater, but it is noisy too, so it goes in the other room unless it can't keep up with the cold.
The heat exchangers certainly interfere with conversations and TV, though.
Joel
