Water Heating

I. Rapid Heat Response can be required

In the UK, there can be very rapid air temperature changes that can require a large input of energy in a short space of time. It is difficult to provide a sustainable heating system in these circumstances but it is possible with a very large capacity ground source or air source heat pump. However, a natural gas, LPG or oil fired boiler will reduce the capital cost significantly with only slightly higher operating costs.

Both heat pump types (Ground & Air Source) will be required to supply Low Pressure Hot Water at 55°C for at least two hours. Conventional boilers will be able to supply at 65°C and this will optimise the efficiency of the Air Handling Unit.

II. Heat Supply to Air Handling Unit

To ensure that the optimum pool room air and pool water
temperatures are always achieved, the AHU will incorporate heat exchanger coils to transfer the heat piped from the separate heat source described above.

In installations where a heat pump is used, special up-rated emitters and fan systems are used to compensate for the lower heating circuit temperature. If there is no boiler available, then direct electric immersion type heaters can be provided as an option. A high capacity pool water heat exchanger is used to ensure a swift initial warm-up period for the pool from cold.

Most AHU's can also provide a ‘heat demand’ signal which can be used to control the heat source and which also can also incorporate a pool water overheat safety feature.