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Water Heater

Get free cooling as you fulfill your hot water needs


Does your facility have hot, humid areas like kitchens or laundries that need cooling? And would you like to reduce your costs for producing hot water? Our engineers can help you benefit from a heat pump water heater. It can provide free cooling while it produces hot water...all at a fraction of the cost of conventional water heaters.

Features Advantages & benefits
Facility Get the optimal equipment for your application with our facilities consulting service.
Significant savings Operating costs for heat pump water heaters vs. conventional water heaters provide quick payback and on-going savings.
Heat pump water heater basics Learn the basics of how Heat Pump Water Heaters work.

Ask us if heat pump water heaters can lower your costs

Our efficiency consultants have worked with customers in a wide number of industries, helping them analyze their operations and estimate the savings they can realize using this technology. Check out the cost savings information in the table below and then compare it to the needs in your facility. If you think this type of equipment is for you, contact us and we'll work with you to explore it further.

The cooling units associated with a heat pump water heater can be located to provide welcome cooling and dehumidification in just the spots you need. Several types are available that can also provide constant cooling.

Besides saving hot water heating costs, the fresher, drier work areas mean a more comfortable staff and cooler operating equipment.

Significant savings

The chart below gives estimated installation costs, operating costs and savings of heat pump water heaters over conventional gas systems.

* Typical water use for kitchens 1.8 -2 gallons of hot water per meal served

500 1000 2000
Heat Pump Water Heater Tons / Cost 1.5 / $5760 5 / $12,740 10 / $23,740
Operating Cost Per Year $590 $1180 $2360
Water Heating Savings Plus A/C Value $1904 $3807 $7615
Simple Payback 2.7 yr. 1.8 yr. 1.5 yr.

Heat pump water heater basics

The best way to understand the basic operation of a heat pump water heater (HPWH), is to think of it as a "black box", without considering the inner workings. Using this approach, the figure below illustrates the three energy flows involved with a typical HPWH.


Heat pump water heater energy flow

The HPWH makes hot water by removing heat from the heat source, producing a cooling effect. Air-source HPWH, the eat source is usually warm, humid interior air.

HPWHs use a small amount of electricity to upgrade the temperature of the heated water to achieve the desired temperature. The water heating efficiency of a heat pump water heater is always greater than 100%, and usually substantially greater (two to four times). In addition to the water heating output, HPWHs can provide a useful cooling and dehumidification effect with no additional energy input.

The electric energy input results in two useful effects: cooling and heating. The heating output (electrical input + heat removed from the heat source) is applied toward a water heating load. The cooling output is often used to cool and dehumidify the interior of a building. Since HPWHs have efficiencies greater than 100%, water heating efficiency for a HPWH is described by the Coefficient of Performance (COP), instead of using the term "efficiency." The water heating COP is the ratio of the useful water heating output to the electric energy input.

It typically achieves a maximum temperature of about 130-150°F depending on the refrigerant used. While heating water, the HPWH also provides a cooling effect of about 6700 BTUH per kilowatt.

The fundamental principles of operation for a HPWH are the same as those of a room air conditioner or a refrigerator. The basic functional components of a heat pump water heater are the evaporator, compressor, condenser, and expansion device, as shown below.


Heat pump block diagram

Heat is transferred by the flow of refrigerant, taking advantage of the large amount of heat absorbed and released when the refrigerant evaporates and condenses. The flow of refrigerant is caused by the pressure differential created by the compressor. The compressor and condenser operate at higher pressure, so that portion of the refrigeration system is called the high side. The portion containing the evaporator and the expansion device is called the low side. The compressor pulls refrigerant from the evaporator on the low side and discharges it to the condenser on the high side, much like a pump lifting water uphill. The expansion device resists the flow of refrigerant back to the low side, maintaining the pressure differential.