Heat pump water heater. Testing and rating at part load conditions and calculation of seasonal coefficient of performance for space heating

2021 ◽  
Keyword(s):  
Heat Pump ◽  
Coefficient Of Performance ◽  
Space Heating ◽  
Water Heater ◽  
Part Load ◽  
Heat Pump Water Heater ◽  
Load Conditions

Performance of Add-On Heat Pump Water Heater (HPWH) Systems and Their Impacts on Electric Utility Loads

2010 ◽  
Author(s):  
Yahya I. Sharaf-Eldeen ◽  
Craig V. Muccio ◽  
Eric Gay
Keyword(s):  
Heat Pump ◽  
Energy Savings ◽  
Electric Energy ◽  
Electric Heating ◽  
Electric Utility ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Energy Output ◽  
Water Heater ◽  
Heat Pump Water Heater

This work involves measurements, analyses, and evaluations of the performance of add-on, Heat Pump Water Heater (HPWH) systems in residential and small commercial applications. Two air-source Heat Pump (HP) systems rated at 7,000- and 12,000-BTU (2.051- and 3.517-kWh), were utilized in this work. The two HPs were retrofitted to two 50-gallon (189.3 liters) electric-resistance storage water-heaters with their electric heating elements removed. A third, standard electric water-heater (EWH), was used for comparison. The testing set-up was fully instrumented for measurements of pertinent parameters, including inlet and outlet water temperatures, inlet and outlet air temperatures of the HPs, temperature and humidity of the air in the surrounding space, volume of water draws out of the storage heater tanks, as well as electric energy consumptions of the systems. Several performance measures were used in this work, including the Coefficient of Performance (COP), which is a measure of the instantaneous energy output in comparison with the energy input; Energy Factor (EF), which is an average measure of the COP taken over extended periods of time; and the First Hour Rating (FHR), which is a measure of the maximum volume of hot water that a storage type water-heater can supply to a residence within an hour. The results obtained clearly indicate that, HPWH systems are much more efficient as compared to standard EWHs. While the average value of the EF for a standard EWH is close to 1.0, the HPWH systems yield EFs averaging more than 2.00, resulting in annual energy savings averaging more than 50%. The results also showed that, HPWH systems are effective at reducing utility peak demand-loads, in addition to providing substantial cost savings to consumers.

Performance Comparison among Heat Pump Water Heaters Working with R32, R134a and the Mixture of R32/R134a

2012 ◽  
Vol 512-515 ◽  
pp. 1295-1298
Author(s):  
De Feng Ding ◽  
Shi Jie Liu ◽  
Chao Yu Zheng ◽  
Wen Sheng Yu ◽  
Wu Chen
Keyword(s):  
Power Consumption ◽  
Heat Pump ◽  
Average Power ◽  
Input Power ◽  
Performance Comparison ◽  
Coefficient Of Performance ◽  
Water Heater ◽  
Heat Pump Water Heater ◽  
Discharge Temperature ◽  
Average Power Consumption

A general air-source heat pump water heater originally designed to work with R134a was reconstructed as experimental rig for performance studies on systems using different refrigerants including R32, R134a and the mixture of R32/R134a which mass ratio is 1:5. Experimental results showed that the power consumption of the heat pump water heater charged individually with R32 would greatly exceed the system’s original pre-set maximum input power. When the leaving water temperature was increased from 18°C to 58°C, the average discharge temperature of the heat pump charged with R32/R134a mixture was 13.6% higher than that with R134a. The average power consumption of the heat pump with R134a was 253.5W less than that with R32/R134a mixture. However, the average COP (Coefficient of Performance) obtained by that with R32/R134a mixture was 0.83 higher than that with R134a.

scholarly journals Heat Pump Water Heater For Cold Climate – Canada

2021 ◽  
Author(s):  
Afarin Amirirad
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Residential Buildings ◽  
Minimum Energy ◽  
Cold Climate ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Water Heater ◽  
Domestic Hot Water ◽  
Heat Pump Water Heater

Considering the large energy consumption of conventional water heaters in residential buildings, the performance of a new type of water heater has been characterized through conducting experiments and numerical modelling. The specific water heater investigated in this work benefits from heat absorption from the indoor air, denoted as the air source heat pump water heater (ASHPWH), and is located in the Archetype Sustainable Twin House B in Toronto. The experiments have been conducted under three different indoor conditions associated with temperature and humidity. The coefficient of performance (COP), which quantifies the ratio of heating capacity to the consumed power of ASHPWH, ranges between 1.5 and 5, depending on the indoor dry bulb and water inlet temperatures. A TRNSYS model of ASHPWH has been constructed based on the obtained experimental results and has subsequently been integrated with a TRNSYS model of the Archetype Sustainable House (ASH). The numerical results were verified with the experimental data. The model results suggests that after employing ASHPWH, the domestic hot water energy consumption reduces by 60.3% and 53.2% compared to the electric water heater in summer and winter respectively. Due to the energy absorption of ASHPWH from the indoor environment, the heating load of the ASH house increases while its cooling load decreases. Furthermore, the annual electricity consumption of the ASH house due to the required heating and cooling as well as the domestic hot water demand is reduced by 21.3%. Finally, as a consequence of employing ASHPWH, the energy cost and GHG emission were reduced respectively by 22% and 21.7%. By investigating the system in four other Canadian cities, it appears that Vancouver and Edmonton would have the maximum and minimum energy savings respectively.

scholarly journals Heat Pump Water Heater For Cold Climate – Canada

2021 ◽  
Author(s):  
Afarin Amirirad
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Residential Buildings ◽  
Minimum Energy ◽  
Cold Climate ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Water Heater ◽  
Domestic Hot Water ◽  
Heat Pump Water Heater

Considering the large energy consumption of conventional water heaters in residential buildings, the performance of a new type of water heater has been characterized through conducting experiments and numerical modelling. The specific water heater investigated in this work benefits from heat absorption from the indoor air, denoted as the air source heat pump water heater (ASHPWH), and is located in the Archetype Sustainable Twin House B in Toronto. The experiments have been conducted under three different indoor conditions associated with temperature and humidity. The coefficient of performance (COP), which quantifies the ratio of heating capacity to the consumed power of ASHPWH, ranges between 1.5 and 5, depending on the indoor dry bulb and water inlet temperatures. A TRNSYS model of ASHPWH has been constructed based on the obtained experimental results and has subsequently been integrated with a TRNSYS model of the Archetype Sustainable House (ASH). The numerical results were verified with the experimental data. The model results suggests that after employing ASHPWH, the domestic hot water energy consumption reduces by 60.3% and 53.2% compared to the electric water heater in summer and winter respectively. Due to the energy absorption of ASHPWH from the indoor environment, the heating load of the ASH house increases while its cooling load decreases. Furthermore, the annual electricity consumption of the ASH house due to the required heating and cooling as well as the domestic hot water demand is reduced by 21.3%. Finally, as a consequence of employing ASHPWH, the energy cost and GHG emission were reduced respectively by 22% and 21.7%. By investigating the system in four other Canadian cities, it appears that Vancouver and Edmonton would have the maximum and minimum energy savings respectively.

Development and Performance Validation of a Heat Pump Water Heater

2006 ◽  
Author(s):  
H. I. Abu-Mulaweh
Keyword(s):  
Heat Pump ◽  
Testing Procedure ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Experimental Measurements ◽  
Water Heater ◽  
Flow Rates ◽  
Heat Pump Water Heater ◽  
And Performance ◽  
Performance Validation

Heat pump water heater was designed and a prototype was developed and constructed. The performance of the heat pump water heater prototype is described by presenting some experimental test data. The experimental measurements include temperature, flow rates, and power consumption. The testing procedure consisted of evaluating the recovery rate and the coefficient of performance (COP) of the system. The results strongly indicate that heat pump water heater system design is very practical and it provides the consumer with a more efficient hot water heater alternative.

Analysis of Domestic Hot Water Production Efficiency for Detached Houses

2015 ◽  
Vol 797 ◽  
pp. 185-191
Author(s):  
Arkadiusz Gużda ◽  
Norbert Szmolke
Keyword(s):  
Heat Pump ◽  
Production Efficiency ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Water Production ◽  
Water Heater ◽  
Domestic Hot Water ◽  
Air Source Heat Pump ◽  
Heat Pump Water Heater ◽  
Detached House

The article compares two means for domestic hot water production (DHW) for a detached house that is using gas boiler with a closed combustion chamber and air source heat pump water heater (ASHPWH). An analysis of domestic hot water production using an air source heat pump was made taking into account coefficient of performance listed according to the new BS EN 16147 standard. The analysis of outlay related to the investment and operating costs was also performed. Ultimately, the more profitable choice for domestic hot water production was made.

scholarly journals A study on the design and analysis of a gas engine heat pump water heater using shower wastewater as heat source

2019 ◽  
Vol 9 (3) ◽  
pp. 310-318
Author(s):  
Fengguo Liu ◽  
Zhenxi Ma ◽  
Rui Zhang
Keyword(s):  
Heat Source ◽  
Heat Pump ◽  
Primary Energy ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Flow Mode ◽  
Outlet Temperature ◽  
Water Heater ◽  
Gas Engine ◽  
Heat Pump Water Heater

Abstract Shower wastewater contains large amounts of heat, and recovering and utilizing shower wastewater heat energy to heat shower water is of great significance for energy saving. This paper proposed a gas engine heat pump water heater (GEHPWH) using shower wastewater as the heat source. Thermodynamic models were built to evaluate the performance of the GEHPWH and compare it with an electrical heat pump water heater (EHPWH). The results show that the GEHPWH has higher hot water outlet temperature and coefficient of performance (COP) than the EHPWH under the same conditions. Furthermore, the GEHPWH can maintain stable hot water outlet temperature and higher primary energy ratio (PER) in variable water flow mode, which resolves the issue that the conventional EHPWH needs an auxiliary heat source. Finally, based on a case, the GEHPWH reveals smaller energy consumption and lower operating costs compared with three other conventional hot-water schemes.

scholarly journals Theoretical study of heat pump system using CO2/dimethylether as refrigerant

2013 ◽  
Vol 17 (5) ◽  
pp. 1261-1268 ◽  
Author(s):  
Xiao-Wei Fan ◽  
Xian-Ping Zhang ◽  
Fu-Jun Ju ◽  
Fang Wang
Keyword(s):  
Heat Pump ◽  
Mass Fraction ◽  
Coefficient Of Performance ◽  
Space Heating ◽  
Water Heater ◽  
Pump System ◽  
Heat Rejection ◽  
Volumetric Heating ◽  
Heat Pump System ◽  
Heating Capacity

Nowadays, HCFC22 is widely used in heat pump systems in China, which should be phased out in the future. Thus, eco-friendly mixture CO2/dimethylether is proposed to replace HCFC22. Compared with pure CO2 and pure dimethylether, the mixture can reduce the heat rejection pressure, and suppress the flammability and explosivity of pure dimethylether. According to the Chinese National Standards on heat pump water heater and space heating system, performances of the subcritical heat pump system are discussed and compared with those of the HCFC22 system. It can be concluded that CO2 /dimethylether mixture works efficiently as a refrigerant for heat pumps with a large heat-sink temperature rise. When mass fraction of dimethylether is increased, the heat rejection pressure is reduced. Under the nominal working condition, there is an optimal mixture mass fraction of 28/72 of CO2/dimethylether for water heater application under conventional condensation pressure, 3/97 for space heating application. For water heater application, both the heating coefficient of performance and volumetric heating capacity increase by 17.90% and 2.74%, respectively, compared with those of HCFC22 systems. For space heating application, the heating coefficient of performance increases by 8.44% while volumetric heating capacity decreases by 34.76%, compared with those of HCFC22 systems. As the superheat degree increases, both the heating coefficient of performance and volumetric heating capacity tend to decrease.

scholarly journals Thermodynamic analysis of a direct expansion solar assisted heat pump water heater

2017 ◽  
Vol 26 (2) ◽  
pp. 110 ◽  
Author(s):  
Masoud Yousefi ◽  
Misagh Moradali
Keyword(s):  
Ambient Temperature ◽  
Heat Pump ◽  
Coefficient Of Performance ◽  
Water Tank ◽  
Direct Expansion ◽  
Water Heater ◽  
Domestic Water ◽  
Heat Pump Water Heater ◽  
Thermodynamic Performance ◽  
Flat Plate Solar Collector

In this paper, the thermodynamic performance of a direct expansion solar assisted heat pump (DX-SAHP), which is used to heat domestic water from 20˚C to 45˚C, is theoretically investigated. The system includes a 3m2 single-cover flat plate solar collector, 0.150m3 water tank and 70m tube immersed in the water tank as a condenser. The effect of various parameters such as radiation on the collector surface, compressor speed and the ambient temperature on the coefficient of performance (COP) are calculated. Results show that obtained COP is considerably more than that of a conventional heat pump water heater when radiation on the collector is high. Also, increasing collector area and reducing compressor speed enhance COP. The same occurs when the ambient temperature increases. For instance, at an ambient temperature of 15˚C and 450 w/m2 irradiation on collector surface, the calculated COP was 6.37.

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