VRF Heat Pump Boiler for efficient air conditioning
The operation characteristics of a heat pump are totally different to an electric or gas boiler. With a conventional boiler, one kilowatt of energy in gives less than 1 kilowatt of heat to the building. With a typical electrically driven heat pump, one kilowatt of energy in gives a heat output in excess of 2.5 kilowatts. This ratio is known as the Coefficient of Performance (COP).
Heat pumps transfer heat from natural sources (such as air, or water) to warm a building. In cooling mode, a heat pump will take heat extracted from a building and move it elsewhere typically outside the building. This can be back into the surroundings, or the excess heat can be transferred to another part of the building.
A good example of how it works is to take a typical example. Below is the system set up for using a heat pump boiler with Variable Refrigerant Flow (VRF) in a restaurant application.
1. The air conditioning supplies either heating or cooling to the restaurant and bar area. All year round the kitchen requires a large amount of cooling due to the ovens, hobs and the concentration of occupants.
2. The heat that is extracted from the all year round cooling of the kitchen is recovered to heat up the domestic hot water. As the hot water demand for cleaning dishes and hands etc is very high in kitchens, the use of the heat pump to heat up the water will be almost constant during business hours.The domestic hot water can be heated to 45ºC using the Heat Pump Boiler. This effectively pre-heats the water prior to using a gas or electric heater to boost the temperature to 60ºC in order to avoid Legionella contamination.
