Establishing The Heat Emitter Temperatures - Panasonic WH-SDF03E3E5 Series Design Handbook

Note

5.5 Establishing the heat emitter temperatures

Aquarea air / water heat pump – design handbook 07 / 2014
The requirements for the control of legionella propagation in workplaces
are described in the HSE Guide L8.
The hot water demand has the greatest influence on the performance
of solar thermal installations for water heating. A proven relationship
between tank volume and collector surface lies between 50 to 80 litres
per m² of collector surface.
Hot water secondary circulation increases the heat requirement for water
heating and for very long piping lengths it can amount up to 100 % of
the heat requirement for water heating. Hot water circulation pumps
should always therefore be time-and-temperature controlled.
The temperature of the heat emitters at standard outside temperatures
should not be higher than 55 °C, for MCS projects 50 °C at the design
outdoor temperature. Recommended are underfloor systems with supply
water temperatures of 35 °C and radiators with a supply water tempera-
ture of 50 °C. When replacing a conventional boiler heating system, with
an Aquarea heat pump, the supply water temperature should be reduced
as much as possible by installing additional thermal insulation and by
taking redevelopment measures on the building. Conventional boiler
heating systems are operated with supply water temperatures up to
75 °C. Through suitable redevelopment measures, existing radiators
can often be operated at lower temperatures and therefore lower heat
outputs. For this, refer to manufacturers' guidance for details of the the
output of the radiator at lower supply water temperatures.
If it is not possible to reduce the supply water temperature to 55 ˚C, it is
also possible to use supply water temperatures of up to 65 °C by using
the Aquarea HT series.
Establishing the heat emitter temperatures
Project Design
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