How the hot water heat pump works

A hot water heat pump, also known as a domestic hot water heat pump, works independently of the heating system. It draws most of its energy from the air. This is usually the air in the boiler room or utility room. This is where the refrigerant circuit, which you can also find in a similar form in your refrigerator, comes into play. However, it works in the opposite direction. In the refrigerator, the circulating refrigerant transports the heat outside via several stations, while in the hot water heat pump it is transported inside the cylinder to heat the water. Important to know: Refrigerants evaporate at very low temperatures, so the energy of the ambient air is sufficient to bring it to boiling point. This happens in the first important component, the evaporator. The compressor then increases the pressure and therefore also the temperature of the refrigerant. In the next step, the hot refrigerant transfers the energy to the water tank via a heat exchanger and cools down in the process, becoming liquid again. The refrigerant is completely expanded by an expansion valve and the cycle starts all over again. You can find everything you need to know about the operating principle of the heat pump in a separate article.

A hot water heat pump is extremely flexible in terms of installation location and energy source. Boilers or electrical appliances such as tumble dryers or washing machines act as unwanted heating in the boiler room or utility room. Hot water heat pumps use this passive energy in the air to heat the hot water. In general, the warmer the ambient air, the more efficiently the heat pump works. There are two types of hot water heat pump:

CIRCULATING AIR HEAT PUMPS

Circulating air heat pumps draw in air directly from their installation room. They are particularly quiet and efficient, as the fan only has to cope with a low volume flow. Their compact design makes them an ideal choice for renovation projects.

DUCTED HEAT PUMPS

These heat pumps draw air from outside via connected air ducts. This gives you more flexibility in terms of placement, but additional duct connections must be taken into account. Ducted heat pumps can often also be connected to existing ventilation systems.

If you already use photovoltaics or solar thermal energy, your hot water heat pump can be integrated into these systems. The electricity generated by your photovoltaic system can be used directly to operate the heat pump, while the solar thermal system provides additional heat for the storage tank. This allows you to use more self-generated energy for hot water production and reduce the amount of electricity drawn from the grid.

Hot water heat pumps are a real option for providing and heating hot water in your home, as they have numerous advantages:

Renewable ambient heat and energy efficiency

Hot water heat pumps use heat from the ambient air and require additional electricity for operation. By obtaining a large proportion of the heat energy from their surroundings, they can provide energy-efficient hot water production. Compared with water heating systems that burn fossil fuels, they can also help reduce CO₂ emissions. Actual savings depend on factors such as the electricity mix and operating conditions.

LOWER OPERATING COSTS

Using free ambient heat as an energy source significantly reduces your running costs for water heating. You can also save costs by combining it with a photovoltaic or solar thermal system.

EASY INSTALLATION AND MAINTENANCE

Hot water heat pumps have a compact design and require neither gas nor oil connections. This makes installation uncomplicated and flexible. Maintenance costs are also low.

DEHUMIDIFICATION AND MOLD PREVENTION

Operating a hot water heat pump can help dehumidify and cool the room air. This side effect may help reduce the risk of mold growth.

In contrast to hot water heat pumps, conventional heat pumps are designed as a complete system for heating and hot water preparation. They must therefore have a significantly higher output, which is reflected in higher costs for purchase and operation.

Hot water heat pumps, on the other hand, concentrate on their core competence - efficient and cost-effective hot water preparation. To ensure that there is enough hot water for the whole family, the hot water heat pump usually has a cylinder with a capacity of between 150 and 300 liters of water. By the way, every alpha innotec hot water heat pump has an integrated, programmable legionella function. It briefly heats the water in the cylinder to up to 65 degrees Celsius using an electric heating element.

For heat pumps, whether for domestic hot water or space heating, two key figures are crucial for assessing efficiency:

COEFFICIENT OF PERFORMANCE (COP)

The coefficient of performance (COP) indicates how much heat energy a heat pump can generate per kilowatt hour of electricity. For example, a COP of 4 means that the heat pump provides 4 kWh of heat with 1 kWh of electricity. The remaining 3 kWh come from the ambient heat.

ANNUAL COEFFICIENT OF PERFORMANCE

As factors such as the outside temperature and heat demand change over the course of the year, the efficiency of a heat pump also fluctuates. The seasonal performance factor takes these seasonal fluctuations into account and indicates the average efficiency across all operating states.

Generally speaking, the higher the coefficient of performance (COP) and seasonal performance factor, the more energy-efficiently your domestic hot water heat pump operates and the less electricity it needs to produce the same amount of heat.

You don't want to replace your existing heating system just yet or are planning to renovate your home before installing a heat pump just in case? Then a hot water heat pump is a good interim solution to reduce the consumption of fossil fuels. You can replace old instantaneous water heaters and boilers or switch off your oil or gas heating completely in summer and let the domestic hot water heat pump provide the hot water. Installing a domestic hot water heat pump is generally very simple, as no gas connections or oil tanks are required. Our experienced specialist trade partners plan the installation and commissioning quickly and easily.

Hot water heat pumps are a proven technology for energy-efficient hot water production. They use renewable ambient heat and can help reduce the consumption of fossil fuels for water heating.

Thanks to their efficient operation, they can also help lower energy costs over time. Actual savings depend on factors such as your previous water heating system and energy prices.

But perhaps an alpha innotec heat pump that provides both space heating and domestic hot water would be a better solution for your home?

Get in touch with our experts for personal advice.