A. Books have been written on this subject. In brief,both systems are capable of producing identical comfort levels if properly designed. In general, a pumped hot water system will cost more to install than a warm air system, although the use of plastic piping has decreased the difference. Furnaces and boilers are available in similar efficiencies, so operating costs are about the same for either system.
Where summer cooling is required, forced air systems make more sense. There is no reasonable way to use a hydronic system for cooling. You can install individual air handling units, which blow air over chilled water in the system. However, this can be expensive and noisy, and essentially converts the water system to an air system. If a separate...
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