Air-source heat pumps demonstrate their capabilities in Northumberland mansion
NIBE air-source heat pumps and a solar-thermal system are providing heating and hot water for the Grade 2 listed Newton Hall near Alnwick in Northumberland for an electricity cost of £300 to £400 a month — compared with an estimate of nearly £2000 a month for oil to maintain a constant 21°C (at 65 p/l). This house is now owned by Paul Hindhaugh, managing director of Hindhaugh Homes, and comprises 840 m2 in total. Underfloor heating is being used throughout.
There was little the new owners could do to reduce heat loss, and insulation could only be added in the loft. The property also had to retain its single-glazed sash windows.
The most effective approach to heating was perceived to be underfloor heating and renewable technology. Paul Hindhaugh sought the help of Howard Tribbick of HT Energy, who had previously installed a NIBE ground-source system for a detached farm house.
Having established that a ground-source system for Newton Hall would require 10 boreholes but that with all the gardens being formal gardens there was nowhere really suitable to site the boreholes.
The system comprises four 11 kW air-source heat pumps running in a cascade system. One unit is dedicated to hot water. There is a 500 l buffer tank for the central heating, from which all the underfloor heating is run. All rooms are controlled by a thermostat.
The hot-water heat pump is linked to a 500 l tank, which is also linked to a NIBE solar-thermal system.
The solar panels are specifically designed to work with the heat pumps, so a separate solar controller is not needed.
The system has weather-compensated control so it automatically adjusts its temperature according to the outside temperature.
The project won the category for domestic air-source installations at this year’s National Heat Pump Awards.