Where is a pool heat pump installed in relation to the pool and the pump? How do I best utilize the heat that the heat pump produces? Which type of pool heat pump is best for my installation? We try to provide answers to these questions.
Installing a heat pump
A pool heat pump must always be installed as close as possible to the water inlet in the pool. In other words, it must be positioned last before the water enters the pool - after the filter, UV system, chlorine/salt systems, etc. If you do not do this, you will not achieve the optimal heating result.
When installing a heat pump, it is always recommended that you also install a "bypass system". The system is a set of pipes, connectors and valves. The image below shows the principle. Valve no. 1 controls how much water should pass by the heating. Valves 2 and 3 are always fully open when the heat pump is in use, but can be closed if the heat pump needs servicing or is taken out of use. If valves 2 and 3 are closed, it is important that valve 1 is fully open.
During normal operation, valve 1 should always be slightly open. It is not recommended to let everything be forced into the heat pump. Doing this will not benefit the heating, and it will reduce the flow in the pool's water circulation. For optimal heating, we suggest that you only let approx. 30-40% of your water pass through the heat exchanger.
How big should it be
When you need to find out how big your heat pump should be, you need to know how many m3 your pool contains (calculate size here) Most manufacturers state how many m3 a given heat pump can be used for. Always choose a heat pump where the number of m3 is "in the middle or at the start" of the recommended range. For example, if one heat pump says 20-35 m3 and another says 30-50 m3 - and you have a 35 m3 pool, then you should choose the one rated from 30-50 m3. If you have a 25 m3 pool, you can choose the 20-25 m3 one, but you can also choose the larger 30-50 m3 one if you prefer faster heating at the start of the season or, for example, turn off your heat pump for periods (perhaps it is at your summer house that you only visit occasionally)
Daily operation will not be either more expensive or cheaper by buying a heat pump that is too large, but if you buy one that is too small, you may find that operation becomes disproportionately expensive. Ask your dealer for advice if you are in doubt.
Split version
A pool heat pump actually consists of 2 main parts - a heat exchanger and the heat pump itself. The heat pump must always be placed outdoors, and the heat exchanger must always be installed in the pool's water flow. In some situations, we recommend buying a heat pump where the heat exchanger is installed in its own unit. Insulated copper pipes run between the heat pump and the heat exchanger and must be installed by a refrigeration technician. The solution is recommended if the pool equipment is located indoors, or space is limited. The heat pump unit can be placed optimally within 4 meters; if necessary, it can be placed up to 12 meters away.
An additional advantage of the split pump is that it does not need to be drained for the winter if the equipment is in a frost-free room.
What does it cost to use
Consumption depends on many factors. Is the pool located indoors or outdoors. Is it covered. Is it in-ground. Is there a lot or a little wind. How big is the pool. What are the soil conditions like - and so on. In other words, it can be really difficult to give a figure.
If you ask pool owners in Denmark, most will say that they spend between 4,000-5,000 per season on heating from May to October at a water temperature of 25-28 degrees, with a kW price of 2.25 and an in-ground pool of 30-40 m3