Integrated Water Heater Research Articles

Experiment-based optimization of an energy-efficient heat pump integrated water heater for household appliances

Novel experimental-based study aims to determine the extent to which performance parameters of water heater system are altered when the heat pump is integrated and to clarify the optimum values of system variables by means of an optimization procedure using reliable experimental data. Considering compressor speed, air flow over evaporator as variables, experiments for both conventional electrical resistance and proposed heat pump integrated water heater for household appliances were conducted. Energy consumption, noise level and operating time were recorded. Experimental results reveal that energy consumption for heating 4 L water up to 50 °C is decreased by up to 26% in heat pump integrated water heater system, whereas noise level and operating time is increased by minimum 0.9 dBA and 65 min, respectively. Time-averaged COP value ranges in between 3.0 and 3.54 in the experiments, but for more realistic ambient temperature cases it may increase up to 7.5. Multi Objective Particle Swarm Optimization algorithm was performed for system components using curve fitted experimental data for the optimum values of system variables by considering energy consumption, noise level and operating time as objectives. Results lead to 17% decrease in energy consumption, 3.9 dBA increase in noise level and 82 min longer operating time.

Experimental evaluation of solar integrated water heater

This paper presents an experimental evaluation of portable modified conventional buckets of 10 l capacity. Out of ten modified portable storage, best three cases (viz. Non-insulated open plastic bucket (OPB), Non insulated plastic bucket top surface covered with a transparent cover (CPB), and Insulated plastic bucket closed with a transparent cover (ICPB)) are discussed. Maximum temperature rise after two hour time duration OPB, CPB, and ICPB are 29.82%, 47.36%, and 21.49% respectively as compared with the initial value the temperatures (22.8 ℃). At 14:45 hour CPB temperature reaches 35.6 °C which is 17.88 and 23.61% higher values as compared to the OPB and ICPB units. Net saving due to utilization solar energy in CPB for a range of 35-50°C is net saving increased by 12.34%, 25.76%, 40.73%, 57.93%, 76.45%, and 97.18% from 2017 to 2022 as compared with the saving in 2016.

Experimental study on the performance of a multi-functional domestic air conditioner with integrated water heater

The recovery of condenser heat is concerned one of the most effective methods to curb energy consumption in residential dwellings. Aiming at recovering the condenser heat of domestic air conditioner, this paper experimentally studied a multi-functional domestic air conditioner with integrated water heater (MDACWH) which can effectively provide space – cooling and domestic hot water simultaneously. The dynamic operation characteristics, such as hot water supply and energy efficiency were tested to verify the availability of the MDACWH. The results showed that the MDACWH can effectively heat the domestic hot water without losing its cooling capacity. It was also found that with the use of MDACWH, the coefficient of comprehensive energy performance of the MDACWH was about 1.58 times higher than that of the unmodified experimental unit. Furthermore, the water-heating time was shorten remarkably from 128.5min to 22.0min. The novel domestic air conditioner, compared with the unmodified initial prototype, can be more practical and provide significant energy savings in space-cooling and hot water supply.

Modeling of a split type air conditioner with integrated water heater

Abstract This paper presents a steady state simulation model to predict the performance of a small split type air conditioner with integrated water heater. The mathematical model consists of submodels of system components such as evaporator, condenser, compressor, capillary tube, receiver and water heater. These submodels were built based on fundamental principles of heat transfer, thermodynamics, fluid mechanics, empirical relationships and manufacturer’s data as necessary. The model was coded into a simulation program and used to predict system parameters of interest such as hot water temperature, condenser exit air temperature, evaporator exit air temperature, mass flow rate of refrigerant, heat rejection in the condenser and cooling capacity of the system. The simulation results were compared with experimental data obtained from an experimental rig built for validating the mathematical model. It was found that the experimental and simulation results are in good agreement.

Domestic air-conditioner and integrated water heater for subtropical climate

The technology of using a heat pump for space conditioning and domestic hot water heating in residences has been developed for half a century. The earlier air-to-water heat pumps and water-heating heat pumps suffered from drawbacks like high costs, unreliable operation, and inflexible applications. They were not well positioned in the market to attract customers. This paper introduces a novel air-conditioning product that can achieve the multi-functions with improved energy performance. The basic design principles and the laboratory test results are presented. The results showed that by incorporating a water heater in the outdoor unit of a split-type air-conditioner so that space cooling and water heating can take place simultaneously, the energy performance can be raised considerably.