Most outdoor swimming pools that Kiwi’s have at home are for use over the summer period. Heating the pool in the shoulder seasons extends the use and fun factor. Pools are often heated with Solar panels or pipes, or stand-alone appliances like gas heaters or heat pumps.
But very good use of the home's central heating system is to enable it to also heat the pool or custom-made spa. This means that one appliance can be used to cover both requirements – heating the home in winter and the pool in summer.
This spreads the capital cost of central heating and minimises the cost of heating a pool or spa. Of course, indoor pools can also use the home's central heating system to heat the pool and the pool room. As the home and pool heating is required at the same time, larger capacity units are required, but it is easily achieved and again, makes good sense.
The method of heating a pool from the central heating of the house is to divert the heated water that normally goes to the radiators or underfloor, to a special heat exchanger that is connected to the pool. The heat exchangers are small and have no moving parts so have a long service life. Controls are connected to enable the pool to be heated up to typically 26 – 28°C.
The water in the central heating system does not mix with the pool as the heat exchanger keeps the two separate but just passes the heat from one to the other. This works out very cost-effective as a heat exchanger for heating a pool is far less expensive and more reliable than a dedicated appliance for heating the pool.
Just like in-slab underfloor heating, a pool or spa takes a reasonable amount of time to get up to temperature and then requires only a small amount of heat to maintain temperature.