Our latest case study:

12kW Dimplex A-Class ASHP:

The property previously had an ageing oil boiler which had become increasingly more unreliable and expensive to maintain. The existing oil storage tank was also taking up valuable room in the garden.

The home owner, Rod was keen to look at an alternative due to the inconvenience of relying on oil deliveries and the volatility of oil prices throughout the year. Having already installed a solar photovoltaic system, he had investigated a number of renewable heating solutions for the property and decided that an air source heat pump would be the best match for his property and lifestyle. 

The air source heat pump:

Air source heat case study

The Dimplex A-class is a new product which has been designed for the UK heating market and has been optimised for the UK climate.

The heat pump can provide water flow tempertures of up to 65°C, so there can be less of a requirement to upgrade the existing raditators in a retrofit installation.

The property at a glance:

A 4-bedroom detached house in Clevedon in the south west of England.

  • The property is off the mains gas grid and previously used a 10-year old combination oil boiler to provide heating and hot water
  • Property has loft insulation and double glazing
  • The total floor area 157 m2

Benefits of the system:

  • The Dimplex A-class system can often operate in conjunction with the existing radiators. For the Clevedon site we were able to use a flow temperature of 45°C to maximise the efficiency and the Renewable Heat Incentive benefit without having to change any radiators
  • A new 210 litre hot water tank was installed in conjunction with the installation to provide all of the hot water to the property via the air source heat pump
  • The system is a single closed unit so there is no need to install any additional refrigerant pipework to an indoor unit, making the installation straightforward. In Rod’s case the installation was completed within 3 days
  • Simple control - the user interface runs the complete home heating system. It’s used to set the house temperature and timings, and to control the heat pump. There's no need for a separate heating thermostat.  The interface has clear menu icons, and an intuitive rotating and push control button, making the system simple to operate and control

Performance:

  • The heat pump was installed in early 2014 and since that time we have measured all of the electrical energy consumed by the heat pump, including that for back-up heaters and circulating pumps and also how much heat the heat pump has produced and the ratio of heat to electrical energy, usually called the Seasonal  Performance Factor (SPF) is 3.46
  • The monthly average SPF including the average external temperature is shown in the graph below 

Running costs:

For the period from March to December 2014:

  • The total electricity energy used by the system was 3,589 kWh. Based on the EDF Energy standard variable tariff rate of 14.94 per kWh for the south west region, the total running cost for the air source heat pump to date would be £536.20 (Prices are based on a payment method of Monthly Direct Debit, as at October 2014. All rates are inclusive of VAT).

Living with the ASHP:

“It’s very comforting to know you get up in the morning, the temperature is exactly the same not up and down, it makes very comfortable living”.

Listen more to Rod as he talks about his experiences with having an air source heat pump installed at home, you can also learn more about the technology and watch the installation at Rod’s home.

 

Watch video: Customer heat pump experience interview

Installation of an air source heat pump (ASHP)

So you know what to expect if you have an air source heat pump installed, we filmed one being fitted from start to finish.

Watch video: Customer heat pump experience

Customer heat pump experience

Listen to Rod Davidge as he talks about his positive experiences with having an air source heat pump installed at home.

Further ASHP case studies:

Property 1

An air source heat pump installed at a property in Cranleigh

16kW Daikin Altherma Low Temperature Air Source Heat Pump:

Chris and Rosy Kidd decided to renovate their Victorian house to create a contemporary open-plan living space. With a second child on the way, the family were keen to make their home as comfortable and economical to run as possible. They have decided to replace their old gas boiler with a 16kW Daikin Altherma low temperature split system with a 200L hot water tank.

An air source heat pump Daikin outdoor unit at Cranleigh case study property

The property at a glance:

3-bedroom Victorian semi-detached house in Surrey:

  • The property is connected to the gas mains and was previously heated using the 15+ year old gas boiler
  • Wood burning stove was installed as part of their house renovation
  • Good level of insulation (filled cavity wall/loft insulation)
  • Building design heat loss: 8 kW. (To meet all household heating requirements)
The Daikin ASHP Indoor Hydrobox unit installed at case study property- Cranleigh

Benefits of the system:

  • Constant comfortable temperature throughout the house
  • Outdoor unit is located to the side of the house
  • 210L hot water cylinder provides plentiful hot water for the family with two young children

Renewable heat incentive (RHI):

  • Renewable Heat Incentive (RHI)(1) payments are available for eligible ASHP installations.
  • The tariffs,set by DECC is currently set at 7.3p/kWh for the renewable heat generated by an air source heat pump, paid for 7 years
  • The Renewable Heat Incentive payment for this property is £940.61 per annum (based on the properties EPC heat demand of 21,475 kWh)
The new 200L hot water cyclinder installed as part of the ASHP installation at Cranleigh

Running costs:

For the period 6 months from 21/01/12:

  • Total electricty cost £185.30 (Information provided by customer)
  • Total energy used by the ASHP 1,690 kWh
  • Internal temperature kept at 17°C
Photo of Chris Kidd, former EDF Energy employee

Living with an ASHP:

"I was aware of the trial that EDF Energy were carrying out and it was a great incentive for me to try this new technology which I knew was more efficient rather than replace it with an existing or a new gas boiler."

Chris Kidd, Cranleigh, Surrey former EDF Energy employee.

Property 2

An air source heat pump installation of a high temperature Daikin Altherma at Newark

Daikin High Temperature Air Source Heat Pump - Newark:

The family wanted to replace the existing oil fired system with a more efficient heating system to reduce running costs and CO2 emissions.

After the initial consultation and site survey, EDF Energy recommended installing a Daikin high temperature air source heat pump (ASHP) as the most suitable option.

The air source heat pump outdoor unit installed at Newark -  A high temperature Daikin Altherma

The property at a glance:

  • Large 5-bedroom detached family house in rural location
  • Off-gas grid
  • Previously used oil fired boiler replaced with Altherma high temperature (HT) 16KW ASHP
  • Double glazing, cavity wall and loft insulation
The installation of an air source heat pump using the existing property radiators

Benefits of the system:

  • Daikin HT system works in conjunction with existing radiators and under-floor heating
  • Daikin HT ASHP comfortably provides all their heating and hot water requirements throughout the year
  • There are no chimneys, flues or fuel storage tanks needed
  • The system is safe to use as there is no flammable fuel usage or potentially toxic flue gasses

Renewable heat incentive (RHI):

  • Renewable Heat Incentive(1) (RHI) payments are available for eligible ASHP installations
  • The tariffs,set by DECC is currently set at 7.3p/kWh for the renewable heat generated by an air source heat pump, paid for 7 years
  • The Renewable Heat Incentive payment for this property is £950.46 per annum (based on the properties EPC heat demand of 21,700 kWh)
The Daikin high temperature Altherma Indoor unit installed under the kitchen workspace

The system consiststs of three main components:

  • The outdoor unit located directly outside the house, to the rear
  • The indoor unit, conveniently placed in the utility room, replacing the old oil fired boiler
  • System is compatible with the existing Megaflow hot water storage cylinder
Existing 200L unvented hot water cylinder retained

System performance:

The installation has been running well since commissioning, delivering water flow temperatures of up to 60°C for heating (under-floor heating around 40°C) and hot water storage temperature of up to 70°C.

This meant that existing radiators on the first floor could be used with confidence and the existing hot water storage meets the family requirements. According to the manufacturer, the Altherma HT system is capable of producing hot water at 80oC without any supplementary heater back-up if required.

Case study participant Mr Cox - Newark

Living with an ASHP:

“We’ve been down to – 8°C and −10°C and we’ve still kept the house warm through the winter”

Tony Cox, Newark
EDF Energy employee

Property 3

The installation of an Air Source Heat Pump at trial site in Canterbury

ASHP case study - Canterbury:

Peter and his wife Inga had recently moved to a detached house in rural Canterbury. As part of the house renovation project they decided to replace the old hot-air heating system with a more efficient heating system that could reduce running costs while maintaining a comfortable environment.

As a renewable energy enthusiast Peter was aware of the benefits that air source heat pumps (ASHPs) could offer. So the family opted for a 16 kW LG Therma V low temperature split system with a 210L Kingspan Aerocyl hot water cylinder

The air source heat pump outdoor unit installed at the property in Canterbury

The property at a glance:

The property at a glance:

  • Large 4-bedroom detached house in rural Canterbury.
  • Off-gas grid location
  • The house was previously heated by an Elvaco air ventilation electric heating system.
  • A wood burning stove was installed as part of the house renovation.
  • Good level of insulation (Filled cavity walls and loft insulation).
  • Building design heat loss: 9.8kW. (To meet all of the household heating requirements)
The air source heat pump with underfloor heating installation on the ground floor

Benefits of the system:

  • The ASHP system works well with under-floor heating
  • The outdoor unit is located outside at the back of the house
  • A 210L hot water cylinder provides plenty of hot water for their needs
  • Low noise level 60 dB at 1 metre

Renewable heat Incentive (RHI):

  • Renewable Heat Incentive(1) (RHI) payments are available for eligible ASHP installations
  • The tariffs, set by DECC is currently set at 7.3p/kWh for the renewable heat generated by an air source heat pump, paid for 7 years
  • The Renewable Heat Incentive payment for this property is £710.80 per annum (based on the properties EPC heat demand of 16,229 kWh)
The Installation of the air source heat pump indoor unit

Running costs:

  • 12 months total energy costs £1,090 Blue+Price Promise April 2014 tariff
  • 12 month of energy use 9,403 kWh (as from 19/09/2011) used by the ASHP
  • Internal temperature kept at 20°C
Air source heat pump case study participant Mr Corkhill

Living with an ASHP:

"We’re in a very lucky situation in terms of working out the advantage of the system because a neighbour who has an identically built house, with the same amount of insulation, has given us a full breakdown of their bills over the last few years and we’re using a half the number of kilowatt hours they use. It’s saving us something like £1,200 a year on the basis of their bills. So we’re very happy with that."

Peter Corkhill, Canterbury

Property 4

The installation of an air source heat pump in Somerset

ASHP case study - Somerset:

Anna lives in rural Somerset in a semi-detached home with her family. As a former Energy Efficiency Adviser at EDF Energy she’s fully aware of the benefits that air source heat pumps (ASHPs) can offer.

Heating the home with an oil-fired boiler was becoming expensive. So the family decided to replace it with a more efficient heating system that could reduce running costs while maintaining a comfortable environment. They opted for a Nibe 8kW low temperature ASHP.

The air source heat pump outdoor unit installed at case study property in Somerset

The property at a glance:

  • 3-bedroom semi-detached property in rural Somerset.
  • Off gas grid.
  • Convector radiators throughout the house.
  • Wood burning stove.
  • Double glazing, cavity wall and loft insulation.
  • Building design heat loss: 6kW. (To meet all household heating requirements)
The installation of a new 200L water cylinder as part of the air source heat pump installation

Benefits of the system:

  • 8kWh Nibe LT ASHP works well using a combination of new and existing raditors
  • Compact outdoor unit located outside at the back of the house
  • 200L water cylinder provides plentiful hot water
  • Since installation, the ASHP has delivered a seasonal Coefficient Of Performance of 2.5. (This is the comparison of the input energy to the heat energy produced by the ASHP)
  • Low noise level 56 dB at 1 metre

Renewable heat incentive (RHI):

  • Renewable Heat Incentive(1) (RHI) payments are available for eligible ASHP installations
  • The tariffs,set by DECC is currently set at 7.3p/kWh for the renewable heat generated by an air source heat pump, paid for 7 years
A couple of radiator were upgraded during the installation of the air source heat pump

Running costs:

For the period 12 months from October 2011:

  • Total energy cost £1,149. (EDF Energy Eco 20:20 Tariff)
  • Total energy used by the ASHP c.7.500 Kwh for the first year
Air source heat pump customer

Living with an ASHP:

“We love the ASHP, it provides a constant ambient comfortable temperature throughout the house. The [old] heating system was timed to come on for a couple of hours in the morning and again in the evening so there used to be cold periods as we couldn’t afford keep the heating on all the time and it would take a while to warm up again whereas now it’s always warm.”

Anna Edwards, Somerset (former EDF Energy employee)