Heat Exchangers

The heat exchanger has an outer shell which contains a multitude of small bore tubes; imagine a kitchen mug and its side and full of children's drinking straws. The hot water from the house boiler circulates between the "mug" and the "straws"; the pool water flaws through the "straws" and is heated by them. The two waters do not mix.

The water from the house heating comes through pipes, which are connected to the heat exchanger.
The pool water thermostat controls the pool temperature.
When the desired temperature is in excess of the actual pool water temperature, a small heating circulation pump turns on and draws the water from the central heating system. This flows on to the heat exchanger where it loses heat to the pool water; returning to the boiler some 4-5°C (40°F) cooler. The house boiler will continue working. When the temperatures are equal or when the actual water temperature is in excess of the desired level, the heating circulating pump is turned off; the house boiler is then not cooled down and turns itself off when it reaches its running temperature.

Therefore to heat the pool the following must happen:
- The filter pump must be running
- The house or pool bailer must be turned on and available to provide heat.
- The heating switch on the main control panel must be an.
- The pool water thermostat must be set at a temperature greater than that in the pool.