Case Study – Family home install safe, low  running cost heating system

Location: Outskirts of Denbigh, Denbighshire

Brief: Hafod were appointed to design and install a new heating system.  The family have recently had children and they wanted a more sustainable heating option that could heat the house to a comfortable ambient temperature 24/7.

Execution:  The home was built in 2007 and had a mains gas ‘combi’ boiler connected to radiators for the heating and the combi also provided instant hot water.    The main problem with the existing heating system was that it was difficult to regulate the heat and it proved expensive to run being on all the time.  The radiators also posed a danger to the infants as they could often reach 80 degrees.

After a site meeting and various consultations with the client, Hafod selected a low temperature air source heat pump coupled to a bespoke retrofit underfloor heating system to the ground floor.

There was a couple of challenges, the first being that there was no space for the outdoor heat pump (due to walkways around the house) the second was that the properties concrete floor could not be dug up as it disturb the foundations and would void the NHBC warranty.

Hafod installed a ‘split’ air source heat pump which allowed the heat pump to be installed upto 30 meters away from the property.

The underfloor heating system installed was an overlay system encompassing a special low depth liquid screed resulting in an additional finished floor level of just 18mm.  The existing doors were planed. The skirting board was not touched during installation.

The underfloor heating now runs at 30-35 degrees and the radiators upstairs were changed from steel to aluminium to increase the heat output.

Hafod also installed a 2.7Kw solar PV system using LG panels to offset the running cost of the heat pump by generating electricity to run the compressor.

Technologies installed

  • Heating: Split Air source heat pump using an 11kw Daikin Low temp
  • Electric: 7Kw Solar photovoltaic system
  • Emitter: Overlay Underfloor heating for the ground floor and aluminium radiators/ fan convectors for the first floor.
  • Hot Water: 30 Tube evacuated tube system as a standalone system.
  • Other: Water diversion switch, voltage optimiser, LED lighting, Heat pump monitor, Solaredge home automation system including smart switches/socket. Full cloud based monitoring of the heat pump, solar and underfloor heating system.

Customer benefits

  • The Customer will benefit from lower heating costs all year round due to the air source heating running at low temperatures. The customer has recorded a C.O.P of 3.25 in the winter which works out 20% cheaper than mains gas.  The Renewable heat payment of £700 / year ensures the project is near fully funded.  In monetary terms this will result in a financial benefit of £900/year.
  • The Solar PV system will also help to run the air source heat pump.  The customer will also receive feed in tariff and export payments for 20 years.
  • The low temperature heating system ensures a safe, comfortable environment for the family. There is no requirement for a carbon monoxide device any more.  The maintenance costs have reduced and they have cancelled their gas heating contract with British Gas.
  • WiFi monitoring system ensures the house is kept at safe temperature and alarm is sent to the customer if the average indoor temperature falls below 20 degrees.

The house re-sale value has increased by 15% since carrying out the upgrades.