Secondary Hot Water Returns
Kensa provides advice on using secondary hot water returns with heat pump systems to ensure hot water is immediately available for properties.
What are secondary returns?
These are used to avoid excessive water draw off before the hot water at the tap is at the correct temperature.
Heat pumps & secondary returns
Any pumped return promotes mixing, destroying stratification within the hot water tank. This, due to the lower stored temperature, can result in noticeably cooler hot water at the taps.
Trace heating tape
The ideal arrangement to reduce the temperature drop of the hot water is to use trace heating tape, which is self-regulating and linked to a time clock.
As an alternative to trace heating tape, a flow boiler in the return pipe can be used. However, this is less efficient and more costly due to the water pump and additional pipework required.
To keep the additional energy required to maintain the hot water temperature to a minimum, all of the hot water pipework needs to be well insulated.