The American Water Heaters heat pump water heater uses a heat pump system that is very much like a refrigerator running in reverse to heat the water. The heat pump does not make heat, but instead takes heat from the ambient air in the room and pumps it into the water in the tank. The heat pump’s compressor uses only 850-watts to operate yet can transfer over three times the amount of heat into the water that the 850-watts of energy could make using resistance heating. The heat pump can also aid in cooling and dehumidification of the air in the room in addition to heating the water.

The American Water Heaters residential hybrid electric heat pump model HPE10280H045DV has an 80-gallon tank and has three standard modes of operation.

• The Efficiency Mode uses just the heat pump to heat the water yet if the ambient air temperature or, water temperatures are outside the optimum range for the heat pump will revert to using the resistance heating elements for water heating. In the Efficiency Mode the Energy Factor is 2.3 and a First Hour Delivery of 70-gallons is provided.
• The Hybrid Mode uses a combination of the heat pump and resistance elements heating the water to provide the most economical heating while meeting your needs. In the Hybrid Mode the Energy Factor is 2.3 and the First Hour Delivery is 84-gallons.
• The Standard Mode uses just the resistance elements to heat the water functioning as an ordinary electric water heater and is the least efficient mode of operation.  In the Standard Mode the Energy Factor is .85 and the First Hour Delivery is 76-gallons.

The American HPE10280H045DV has a 4500-watt upper and 2000-watt lower element made of corrosion resistant Incoloy to provide resistance heating when conditions are not optimum for the heat pump or, water usage is higher than the heat pump can meet or, when Standard Mode is selected. There is also a function where you can program a vacation on the control panel. The vacation setting will maintain a 60-degree temperature in the water heater to prevent freeze damage.

The American Water Heaters residential hybrid electric heat pump water heater is an 80-gallon tank that measures 24.5” wide and is 81.5” high, tipping the scales at 410 lbs. The water heater requires a minimum of 240-volts single phase, and a circuit breaker of 25-amps. to provide electrical power for operation. Also required is a minimum room size of 750 cu. ft. for operation of the heat pump, and a condensate drain. The residential hybrid electric heat pump model HPE10280H045DV comes with an electric powered anode to help prevent corrosion of the tank, T&P valve, 2” non-CFC foam insulation, and a brass drain valve. The water heater is also provided with a 10-Year Limited Tank and a 10-Year Limited Parts Warranty

The American Water Heaters Residential Hybrid Electric Heat Pump model HPE10280H045DV has a 3.1 Coefficient of Performance (COP) which makes the unit energy star compliant. This makes people who purchase and install the unit eligible for rebates under the appliance stimulus program, many state rebate programs, and utility rebate programs. A 30% Income Tax Credit up to $1500 is also available for people who purchase and install this water heater.

The State Premier Hybrid Electric Water Heater model EPX-80DHPT has two ways of heating water built into it. The heat pump uses a reverse refrigeration process pulling room air through the evaporator coil drawing heat from the air in the room then sends the R-134a refrigerant into a coil surrounding the tank of the water to dissipate the heat from the refrigerant into the water in the tank heating it for your domestic hot water use. This process only uses a compressor which draws 850-watts to operate. Since heat is not being made but is only being transferred the process has an energy factor of 2.3 and a coefficient of performance of 3.1. The State EPX-80DHPT also has two resistance heating elements for providing heat when the heat pump cannot operate because of improper ambient temperatures or, a large amount of water is drawn and additional capacity is required. The upper element is a 4500-watt incoloy element and the lower element is a 200-watt incoloy element. Incoloy is a metal, which has proven resistance to corrosion and should prove to be a ling lasting element.

The State Premier Hybrid Electric Water Heater model EPX-80DHPT has three operating modes for the user to choose from. The Efficiency Mode is the most efficient and utilizes only the heat pump for heating the water in the tank. If the ambient air temperature goes outside of the efficient operating range for the heat pump the unit will switch over to heating with the resistance heating elements to provide your hot water needs. The Hybrid Mode will utilize both the heat pump and resistance elements to make hot water and the usage of each will be determined by the unit to provide the highest economy while meeting the demand for domestic hot water. The Electric Mode is the least efficient mode of operation and in this mode the water heater operates like a standard water heater with the resistance elements providing all the heating.

The State Premier Hybrid Electric Water Heater model EPX-80DHPT was a user-friendly LCD display where temperature, operating mode, status, and error messages are displayed with back-lighted buttons underneath where the user can select operating modes, temperatures and also a vacation setting where you can preset the dates of your vacation and the unit will only heat to prevent freeze damage yet turn back on and come up to temperature one day before you return from your vacation. The State EPX-80DHPT has an 80-gallon tank with a factory installed T&P valve, brass drain valve, 2” non-CFC foam insulation, and a powered anode rod to provide corrosion protection. The EPX-80DHPT is 81½” high and 25½” wide weighing in at 410 lbs. The EPX-80DHPT provides a first hour delivery of 70 gallons in efficiency mode with an EF of 2.3, 84 gallons in hybrid mode with an EF of 2.3, and 76 gallons in electric mode with an EF of .85. The State EPX-80DHPT because it cools the ambient air passing through it also will generate condensate from cooling the air and provides dehumidification so it requires a drain for condensate. Maintenance is simple with only the evaporator air filter requiring cleaning similar to cleaning the filter on a room air conditioner. The EPX-80DHPT requires a minimum of 1,000 cu ft of air space for sufficient air volume for operation in the heat pump mode.

The State Premier Hybrid Electric Water Heater model EPX-80DHPT is among some of the most efficient water heaters available and according to State Water Heaters can save the average family about $360 per year on their water heating energy costs. This translates to a savings of about $4200 over the expected 12-year service life of the State EPX-80DHPT. Because of this great savings potential the Federal Government offers an Income Tax Credit of 30% of the cost to purchase and install a heat pump water heater up to a maximum of $1500. Also many states and utility companies are offering rebates and other incentives, which can greatly offset the cost of purchase and installation starting your payback much sooner.

The State Premier Hybrid Electric Water Heater model EPX-80DHPT is provided by State Water Heaters with a 10-Year Warranty.

The Rheem RTG-74DVN Direct Vent Natural Gas Tankless Water Heater is a compact design that measures 25 3/3” high X 14 7/8” wide X 11 1/8” deep and weighs about 55 lbs. The RTG-74DVN meets the stringent SCAQMD rule 1121 requirements for Low NOx emissions. The electronic controls are intelligent controls, which increase efficiency while monitoring safety. The controls also feature self-diagnostics and will display maintenance codes along with temperature settings on the digital display of the remote control panel. There are two remote control panels available for the RTG-74DVN tankless unit, the USC1-117, which is provided with the unit can be set up to 120-degrees F, and the USC-117, which is optional and can be set up to 140-degrees F. The RTG-74DVN has an oxygen depletion sensor, and a film wrap overheat limiter for extra safety. The RTG-74DVN uses category III stainless steel vents for combustion air and exhaust with a built in electric blower, a RTG20002B vent adapter is required for installation. The unit is provided with a power cord and has freeze protection to –30 degrees F. The RTG-74DVN can be linked with another unit using the EZ-Link cable to double the hot water production.

The RTG-74DVN hot water production varies depending on the incoming water temperatures and can produce 7.4 gallons per minute at a 45-degree F temperature rise, 6.7-gpm at 50 degrees F, 5.6-gpm at 60 degrees F, 4.8 at 70 degrees F, 4.2-gpm at 80 degrees F and 3.7-gpm at 90 degrees F. The RTG-74DVN has an energy factor of .82. When the Rheem RTG-74DVN Direct Vent Natural Gas Tankless Water Heater is installed above 3,280’ above sea level a high altitude chips are required that allow operation from 3,280’ – 6,560’ and 6,560’ – 9,840’ elevation.

Rheem RTG-74DVN Direct Vent Natural Gas Tankless Water Heater is provided with a 3-Year Limited Parts Warranty on the entire unit and a 10-Year Limited Warranty on the Heat Exchanger.

The GeoSpring Hybrid Water Heater is one of the most efficient ways you can heat domestic hot water for your home with an Energy Factor of 2.35 operating in the hybrid mode. In fact it can consume up to 62% less energy and save about $320 per year when compared to a regular electric water heater. Based on this tremendous savings of energy the government is offering rebates and tax credits to help offset the cost of buying and installing a heat pump water heater. The rebate programs vary by state and you should check your states program for details before purchasing. The Income Tax Credit is 30% of the price to purchase and install the water heater up to a maximum of $1500. The DOE estimates that if every person buying an electric water heater this year purchased a heat pump water heater carbon dioxide emissions would be reduced by 19.6 billion pounds.

The GeoSpring Hybrid Water Heater has a heat exchanger coil and compressor mounted on top of the unit with another heat exchanger coil wrapping the tank from top to bottom. This heat pump draws room air through the heat exchanger also known as the evaporator on the top of the unit taking heat from the ambient air. This air is cooled and discharged out of the unit cooling the air in the surrounding area. This cooling process also dehumidifies the air extracting moisture from the air so a condensate drain must be provided. The heated refrigerant is then pumped down through the coil surrounding the tank heating the water.

In addition to the heat pump the GeoSpring Hybrid Water Heater also has two conventional 4500-watt elements to meet your water heating needs when conditions are out of the heat pump operating range or, when the demand exceeds the heat pump capacity. The GeoSpring Hybrid Water Heater has four operating modes, which can be selected on the electronic control panel with the status displayed on the LCD screen.

• When the eHeat mode is selected only the heat pump is used for heating the water, this is the most efficient mode of operation but it is also the slowest to recover and if the demand is high such as a large household or visitors may not meet your needs.
• The Hybrid Mode, which is the recommended mode of operation, uses both the heat pump and the elements combined to deliver both higher recovery of the resistance elements and the savings of heat pump operation.
• The High Demand mode is for use when your hot water usage is higher than normal and increases the usage of the resistance elements to deliver a higher recovery rate then reverts to heat pump use when the elements are no longer needed.
• The Standard Electric Mode uses only the resistance elements for water heating and the water heater acts as a standard electric water heater.

The GeoSpring Hybrid Water Heater also can be set for vacations where you can input the number of days from three to ninety days, you are going to be away and the water heater temperature will be lowered to 50-degrees F using the most efficient way to heat the water then turn back up one day before you arrive home again. The GeoSpring Hybrid Water Heater has a fifty-gallon tank, and can have a temperature setting from 100 to 140-degrees F while holding within plus or, minus 3-degrees F. The GeoSpring is 60 ½” high and 21 ¾’ wide, weighing 190 lbs. empty. The GeoSpring Hybrid Water Heater requires 208/240-volts on a 30-amp circuit for operation and has a noise level of 58 DBA when operating.

The GeoSpring Hybrid Water Heater models GEH50DNSRSA and GEH50DXSRGA come with a Limited 1-Year Warranty on Parts and Labor, and a 10-Year Parts Warranty. The GeoSpring can be found at Lowe’s, Sears and other locations with an MSRP of  $1699.

The AO Smith Voltex uses a heat pump to pump heat from the ambient air into the water in the tank yielding an Energy Factor of 2.3 when heating in the efficiency and hybrid modes of operation and a Coefficient of Performance (COP) of 3.1, which means they meet the Energy Star requirements for rebates under the Appliance Stimulus Package, and Income Tax Credits of 30% up to $1500. These rebates and tax credits are a direct result of the government promoting energy saving products and stimulating the economy.

The AO Smith Voltex Hybrid Electric Water Heater model PHPT-80 is an 80-gallon heat pump water heater, which uses an 850-watt compressor to pump the R-134A refrigerant through the heat pump system. The heat exchanger coil and compressor are mounted on top of the unit pulling heat from the air in the room then sends the heat down to another heat exchanger coil wrapped around the tank which heats the water in the tank. The heat pump exhausts cool air into the room and also removes humidity from the air passing through it acting as a dehumidifier, so a condensate drain is required as part of the installation. The AO Smith Voltex PHPT-80 also has two incoloy heating elements, which can heat the water like a typical electric water heater. The upper element is a 4,500-watt element and the lower element is a 2,000-watt element.

The AO Smith Voltex Hybrid Electric Water Heater model PHPT-80 has four heating modes, which can be set by the owner. The Voltex has a control panel with an LCD screen that shows the set point, mode/status, heat pump on, elements on, level of efficiency, and whether the control panel is locked or, not. The Efficiency Mode utilizes only the heat pump for heating the water. The heat pump has an effective use range of 45-degrees F (7.22C) to 109-degrees F (42.8C), if the ambient temperature is out of that range or, hot water usage is higher than the heat pump can produce the hybrid mode should be selected. The Hybrid Mode can utilize both the heat pump and the electric elements to heat the water. In the hybrid mode the heat pump is the primary method used to heat the water but when the demand exceeds a preset level the elements will turn on to help meet the increased demand. The Electric Mode when selected has the water heater operate as a conventional electric water heater with only the elements providing hot water. The Voltex also has a Vacation Mode where the water heater will maintain a temperature of 60-degrees F (15.6C) for use when hot water will not be used for an extended period of time and to prevent freezing damage to the unit.

The AO Smith Voltex Hybrid Electric Water Heater model PHPT-80 has a first hour delivery of 70-gallons in the efficiency mode, 84-gallons in hybrid mode, and 76-gallons in the electric mode. AO Smith recommends installation in a room with 1,000 cu. ft. of size with free airflow in and out of the unit. When a condensate pump is used there is a condensate pump wiring loop that can be connected to a float switch on the condensate pump which when activated by a failed pump will cause the heat pump to shut off and “Condensate Drain Alarm” to display on the control panel. The Voltex has an easy to remove washable air filter, a powered anode rod, brass drain valve, two inches of non-cfc foam insulation, and a factory installed T&P valve. The AO Smith Voltex Hybrid Electric Water Heater model PHPT-80 is supplied with a 10-Year Limited Warranty.

Dedicated Return Line Systems

When a dedicated return line is used the system is comprised of a pipe looping back from the hot water line at the furthest point(s) to either the cold line feeding the water heater or, into the water heater drain connection. A circulator pump is used to pump the water through the loop and a check valve is used to prevent cold water from back feeding through the return line. There is also a valve that is used to throttle the flow in the return line to check the velocity of the water flowing in the loop and prevent erosion of the pipes by excessive flow rates of the water in the pipes. The circulator pump should be constructed from materials, which resist corrosion as the pumps typically used for hot water heating systems typically use cast iron impellers and housings, which will corrode in an open system. Sometimes a plumber may be able to run the pipes in a manner where the recirculation will occur by gravity without the use of a pump. This dedicated return line type system can be installed in new construction and in homes where the return lines can be run without major difficulty.

Cold Water Line Return Recirculation Systems

There are also numerous recirculation systems, which do not require the use of a dedicated return line. These systems are ideal for use in homes where it would be difficult and expensive to run a dedicated return line to the water heater. Many of these systems use a thermostatic valve and pump connecting between the hot and cold angle stop valves under a lavatory sink vanity. Whenever the hot water cools off to the set temperature, the system activates and pumps the cooled off hot water into the cold water supply line until hot water again reaches the fixture. The cooled of hot water is not hot enough to present a problem on the cold side and it rapidly cools off to the ambient temperature. The only down side is if you were wanting to get “cold” water you would have to wait for it to arrive which is quite typical anyway. Many manufacturers such as Grundfos, Watts, Laing, RedyTemp, and Metlund manufacture systems, which can be installed utilizing cold water supply lines for recirculation. With these systems you can easily have hot water waiting for you to use every time and stop pouring gallons of water down the drain waiting for hot water to arrive.

The Navien NR Condensing 98 residential tankless water heaters feature a stainless steel heat exchanger which Navien claims is up to 4 ½ times more life and resistance to erosion over the copper heat exchangers used by other manufacturers. The Navien NR Condensing 98’s also have a cool flue gas discharge, which can be discharged through PVC, a three stage premix burner controlled by dual microprocessors utilizing air pressure and gas pressure sensing to provide the optimum fuel/air mixture modulated to your exact needs.  The dual microprocessors also monitor safety functions and tests themselves as well. The Navien NR Condensing 98 residential tankless water heaters can be fired on either Natural Gas or, LP Gas with an easy conversion when setting the unit up. The “A” models feature a built in tank and recirculation pump which can provide instant hot water at fixtures through out the home at any flow level without having to flow a minimum amount of water to fire the unit and waiting for the unit to detect a flow, fire, then the heated water to travel through the pipes to your point of use, units without the recirculation feature require a minimum flow of 0.5-gpm to fire the unit. The NR-10DU remote controller has a backlighted LCD screen, which reads out diagnostics and error codes as well as controlling temperature and recirculation times with inputs via pushbuttons, which can be locked out to prevent unintentional changes. Multiple units can be interconnected in a cascade system to provide virtually any amount of hot water flow you need. The Navien NR Condensing 98 residential tankless water heaters in residential installations are provided with a 15-Year Parts Warranty on the heat exchanger and a 5-Year Parts Warranty on other components, also provided is a 1-Year Labor Allowance.

The Navien NR Condensing 98 residential tankless water heaters three base models have different capacities.

• The NR-180 fires from 15,000 to 150,000 Btu/h, measures 17”W X 28”H X 14”D weighing 67 lbs. with the “A” model weighing 77 lbs. The NR-180 can produce 3.8-gpm with a 77-degree F temperature rise up to 8.3-gpm with a 35-degree F rate of rise.
• The NR-210 fires from 17,000 to 180,000 Btu/h, measures 17”W X 28”H X 15”D weighing 77 lbs. with the “A” model weighing 86 lbs. The NR-210 can produce 4.5-gpm with a 77-degree F temperature rise up to 10-gpm with a 35-degree F rate of rise.
• The NR-240 fires from 17,000 to 199,000 Btu/h, measures 17”W X 28”H X 15”D weighing 77 lbs. with the “A” model weighing 86 lbs. The NR-240 can produce 5-gpm with a 77-degree F temperature rise up to 11-gpm with a 35-degree F rate of rise.

Some of the common water flows in your home would be a shower, which flows a maximum of 2.5-gpm/9.46- L/min per showerhead, a kitchen faucet, which flows 2.2-gpm/8.3 L/min, and lavatory faucets, which flows 1.5-gpm/5.7-L/min.

A flow switch, which detects water flowing through the unit, controls the heating of water in a tankless water heater and turns on the heater modules maintaining the temperature, which is set by the knob between 95-degrees F/35-degrees C up to a maximum of 131-degrees F/ 55-degrees C. The Bosch PowerStar AE115 requires a 0.6-gpm/2.27- L/min minimum flow to turn on and the Bosch PowerStar AE125 requires a 0.8-gpm/3.03- L/min minimum flow to turn on. The water then flows through the 40-amp heater modules where it is heated to the set temperature. The Bosch PowerStar AE115 has two heater modules and the Bosch PowerStar AE125 has three heater modules. For safety each heater module has a safety cut out switch, which will kill power to the module if the temperature goes too high. Both the AE115 and the AE125 are the same size 15½” X 15¼” X 4½” with the AE115 weighing 20 lbs/9.07 kilos and the AE125 weighing 22 lbs/9.98 kilos. The Bosch PowerStar AE115 and AE125 Electric Tankless Water Heaters are supplied with a Ten-Year Warrantee.

The thermal expansion tanks used on water heaters should be listed as “Potable Water Expansion Tanks” which means they are constructed from materials that are safe to use on drinking water systems. Expansion tanks are also used on hot water boilers but the water in those systems are never consumed so the materials used are different. Make sure the right type of expansion tank is used on your potable water system. The expansion tank should be connected on the inlet side of the water heater and connected by a tee between the inlet to the water heater and the shut off valve on the inlet of the water heater. There should be no valve between the water heater and the expansion tank, which would defeat the protection provided by the expansion tank. The water in the tank will add considerable weight to the expansion tank and it should be adequately supported to avoid placing stress on the pipes. The tank may have a longer line plumbed to it allowing the tank to be remotely mounted. it does not have to be directly on top of the water heater.

Potable Water Thermal Expansion Tanks are made by a few different companies, Watts with their model PLT-5, PLT-12, PLT-20, and PLT-35 tanks used in residential and light commercial, and Amtrol with their Therm-X-Trol model ST-5, ST-8, ST-12, and ST-25V tanks also used in residential and light commercial are very popular. Larger commercial water heating systems would require using an ASME Rated expansion tank. The tanks are made of drawn steel that has a rubber bladder dividing the tank into two sections. On one side there is a threaded connection that allows water to enter the tank. On the other side there is an air valve similar to the one on a tire through which the air pressure of the pre-charge on the air side of the bladder can be adjusted and checked. The pre-charge should match the typical pressure on your water supply system. The air is able to compress which allows the expanding water to enter the expansion tank with only a slight increase in system pressure preventing the water heater tank from experiencing pressure cycles and providing a substantial increase of the service life expectancy of your water heater.

The Crown Mega-Stor Indirect Water Heaters feature a tank constructed from 316l stainless steel and have a stainless steel coil through which hot water from the boiler flows heating the water on the tank. The coil is plumbed on a separate zone on the boiler to control when water needs to be heated. The Crown Mega-Stor Indirect Water Heaters can provide a first hour delivery from 103 to 417-gallons of hot water with a 90-degree rise depending on the size of the water heater and boiler used. The Mega Stor comes in the model MS-26 26-gallon, MS-40 39-gallon, MS-53 51-gallon, MS-79 80-gallon, and MS-119 112-gallon round tanks and the MSH-40H 38-gallon, and MSH-53H 51-gallon horizontal tanks which most Crown Boilers can mount on top of for a small footprint for your heating and domestic hot water package. The Crown Mega Stor Indirect Water Heaters have an removable inspection cap on the top of the round tanks and on the front of the horizontal tanks which can be opened to allow viewing the inside of the tank and the coil. The Mega Stor has an adjustable Honeywell aquastat and a drain at the bottom provided to allow flushing sediment from the tank the tank. The Mega Stor tanks are insulated with 2” polystyrene foam insulation to minimize standby heat loss with a jacket made of high impact plastic. The Crown Mega-Stor Indirect Water Heaters come with a Lifetime Warranty covering leakage on the stainless steel tank and coil.