Heat pump water heaters for small commercial applications are usually air to
water units without refrigerant reversal. These are typically easily installed
packaged units, with or without an integral hot water storage tank. In most
popular applications, they provide useful space cooling while simultaneously
heating domestic hot water. Examples include commercial kitchens, photo labs, and
coin-operated laundries.
A typical unit with 75°F entering room air might deliver 105 gallons per hour
of hot water at 115°F tank temperature while providing about 2 1/2 tons of
useful cooling to the kitchen or laundry room. The hotter the air entering the
heat pump, the greater the cooling and water heating capacity. For example, the
same unit with 85°F entering air might deliver 118 gallons of hot water per hour
and 4 tons of cooling.
This cooling is often delivered through air ducts as "spot" cooling in
kitchens and laundries, rather than trying to cool the entire room. Coefficients of
Performance are typically over 3.0, which means the heat pump heats the water 3
times as efficiently as a standard electric water heater.
One of the heat pump water heater's limitations is that there are relatively
few suppliers. The availability of parts and service should also be considered
in the purchase decision.
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