Combi-system warm water, heating support and swimming pool heating

Location: Nothern Germany Meppen

The installed 19.2 m² s-power solar heating system (120 tubes) feeds through a bare tube heat exchanger into a 1,000 litre combi-stratified storage reservoir with a 200 litre drinking water reservoir.

In addition, the existing 50 KW gas boiler was connected to the combi-reservoir. Underfloor heating, static heating surfaces and the swimming pool heating were also connected to the reservoir through a sinus distributor.

The modulating boiler and heating circulation controlling detects the temperature in the combi-reservoir and keeps it at the calculated temperature level. When there is enough solar energy available in the reservoir the gas boiler remains turned off. If there isn’t enough solar energy in the reservoir the gas boiler heats up the remaining energy demand.

If the solar collector heating system produces a surplus (>80 °C) then the swimming pool filter system automatically switches on and directs the surplus directly into the in-house swimming pool which normally is only heated at night. When the temperature in the combi-reservoir goes below 65 °C, the filter system turns off again and solar energy can be absorbed again.

At night, the combi-reservoir discharges itself through the swimming pool filter operation to the calculated temperature level set by the weather influenced controller so that solar energy can be absorbed by the system again the following day.

The calculated amortisation period of the solar collector system is 5-6 years.

(With a gas price increase of 15% per year)