Swimming pool heater options
Most people who have an outdoor swimming pool also decide to have the pool heated. However, deciding which type of swimming pool heater to select is a challenge since there are a number of alternatives available.
The main factors used to determine which heater option is the most appropriate are normally pool size, regional climate and pool usage.
The different types of available pool heater fall into the following categories -
Gas and propane burning boilers and condenser boilers - condensing heaters and heat pumps - heat exchangers - electric heaters - solar heating systems
Each of the options above has different advantages and disadvantages relating to heat capacity, running costs, maintenance charges, pool size (water volume), maximum heat output, initial costs and fitting charges etc. Factors like the local climate and the level of use play a role in determining which heating option is the best for any given pool.
Cost versus efficiency
Certain types of pool heater like those powered by solar energy, heat exchangers or heat pumps are energy and cost efficient to use. They do however have the drawback of being limited to small to medium sized pools. This is because there are limits to the water volumes and heat outputs that they can sustain.
Larger heating systems like boilers, that burn fossil fuels, have greater heating capacities, but this is balanced by increased running (and installation) costs. In short the more heat and the greater the flow capacity, the higher the cost and the larger and more complex the heater.
In terms of heating power and versatility, a boiler, a stove, or a condensing boiler will offer the most powerful and flexible heating system. Heaters of this type have high flow rates and they can quickly raise water temperatures in very short periods of time. For this reason they are ideal for situations where pools need to be heated up quickly, or where an outdoor pool is in a cold climate requiring a high flow rate of warm water.
Naturally the more the heater is used and the greater the differential between ambient water temperature and swimming water temperature, the greater will be the energy usage.
How to choose a pool heater
In determining what type of pool heater your pool, climate and use levels require, consider the following factors. The importance that you attribute to each one will be based on your own personal needs.
- Pool's size - in other words the volume (and flow rate) of water to be heated.
- Required water temperature
- Level and regularity of use (e.g. daily, seasonal etc)
- Intended swimming season
- Budget (initial and ongoing)
As a rough guide, certain types of heater like those based upon solar energy or heat exchangers, are good for raising the water temperatures by a few degrees, but they are less effective at bridging bigger temperature differentials.
Solar energy is free, but it does require clear skies and sun and heat exchangers have a limited output. Both are comparatively cheap to buy but they have their limitations.
Boiler based pool heaters (including condensers) use a solid fuel like gas, propane or oil. This makes them expensive to run, but also flexible, powerful and capable of heating large pools with big volumes of water. They can also be controlled very accurately and any changes to water temperature can be made quickly with advanced thermostatic controls. The downside to these pool heaters is cost, both in terms of the initial outlay, the ongoing energy usage and any maintenance or repair charges.