01 February 2016
Heating a swimming pool
Efficient heating is vital to ensure that the swimming pool functions properly. The temperature of your pool can affect its performance in a range of ways, including its hygiene, water clarity and bathing comfort. In turn, pool heating can impact everything from the equipment bought to how often servicing is required.
Heating a pool is a relatively straightforward affair and heat retaining pool covers can make heating even more efficient. There is a range of commonly-used pool heating solutions on the market and this blog takes a look at the different options and type of pool to which they are best suited.
Heat pumps are growing rapidly in popularity thanks to their environmental efficiency, convenient installation, and relatively low operating cost. They are particularly well suited to outdoor pools. As these are operational primarily during the warmest months, a heat pump is able to extract much more heat from the environment around the pool (from the air or ground). This makes them very efficient, consuming around 3.5-4.5 times less power than the heat they produce.
However, this efficiency depends upon whether or not the pump uses a direct or indirect unit. A direct unit, as the name suggests, heats water directly. Meanwhile, indirect units, which can heat things other than pools, rely on heat exchangers to warm the water – and thus are naturally less energy efficient.
Pools which use air-source pumps must be placed in an openly ventilated space – either indoor or outdoor. They can be noisy so the noise of the equipment must be taken into account when considering the pool location. Designed to match the average heat loss from a swimming pool, heat pumps also tend to require a longer warm-up period than other types.
While solar panels offer an affordable and eco-friendly solution to pool heating, the UK climate tends to mean that solar panels will not generate enough energy to heat a pool. Having said this, we have designed and built an award-winning energy efficient pool which uses a large number of PV panels on the roof of the pool hall which provides the vast majority of the heat for the pool.
However, solar panels can be used to supplement other heating systems, which can lower running costs over the lifetime of your pool. Solar heaters require panels around 50% of the pool’s surface area in order to provide effective heat, so initial costs can be high.
Gas and oil boilers
Boilers are perhaps the most common means of heating a pool. There are two types of boiler. Direct boilers heat water through the boiler itself; whereas indirect heating involves using a regular boiler with an external heat exchanger.
All boilers must be installed by a qualified technician, and the equipment that comes into direct contact with the water must be adapted to the specific flow rates and chemicals of the water itself. In that regard, they are not as easy to install as heat pumps.
Boilers often have very low running costs – particularly gas boilers. This is, of course, dependent on the supplier which is why you should research gas supplies before purchasing a boiler. Oil boilers, on the other hand, are more effective heaters, but cost more to operate and service and tend to be more expensive than gas boilers. If neither option is suitable, LPG boilers represent a more expensive standalone solution – unless the household already operates a gas cooking system. All boiler systems have a quick heat up time of one to two days, making them perfect for pools that aren’t used frequently.
Alternatively, house boilers can be used to heat the pool through the use of a heat exchanger. Your ability to do this depends heavily on the location and capability of your home boiler.
These completely silent, low-maintenance heaters are compact and fitted to the plant room of the pool system, and provide the cheapest initial cost solution to heating. However, while the initial cost is low, they are the most expensive to run.
Electric heaters have a longer warm-up period and are thus ill-suited to a pool used irregularly. The high electrical demand from electric heating also means an electrical survey will have to be carried out to ensure sufficient capacity.
Whatever heating system is selected, make sure they are bought from reliable companies, ensure the supplier offers continuous support and double-check that the claimed performance is suitable to the UK climate.
This blog has been written utilising information from the Swimming Pool & Allied Trade Association.