What sort of properties are suitable for an air source heat pump?
Air source heat pumps are a suitable complete or partial solution for the majority of existing houses as well as new builds. Most properties that can achieve a reasonable level of thermal insulation could be suitable for an air source heat pump. In order to achieve the highest levels of efficiencies, all properties should have been updated with the basic thermal improvements i.e. cavity wall installation, loft insulation and double glazing. The air source heat pump then needs to be able to meet the maximum heat demand of the property under its maximum (coldest) conditions.
Can an air source heat pump be used in conjunction with other technologies?
Yes, with suitable control systems, air source heat pumps can be operated to act in either a lead or support mode with any other fossil or renewable heating technology.
Will Ecodan work in my home?
The heat loss of your home needs to be calculated to ensure that Ecodan will give sufficient space heating. As a guide a modern house has a heat loss of approximately 50W/m2. So Ecodan would be able to heat a home up to 180m2 (based on a 9kW output). Careful consideration with older buildings needs to be taken, the heat loss of these homes can be much higher than in modern well insulated properties.
How do I buy an Ecodan system?
Ecodan needs to be bought and installed by an Approved Ecodan Installer with the right qualifications. Mitsubishi Electric can provide you with details of your nearest installer.
How much will installation cost me?
Installation costs vary from property to property, but as a guide, costs will be similar to that of a conventional gas boiler. A competent installer should take 1 – 2 days to install and set up the Ecodan system. For new build, as no gas supply is required, costs are actually cheaper.
How easy is it to install Ecodan?
Many house builders are installing Ecodan in new homes. If you have an older property, Ecodan is straightforward to fit and one of our Approved Ecodan Installers will take 1 to 2 days to install and set it up. Unless the property is over 30 years old, the existing radiators can potentially be used. Our specially trained installers will give all the advice needed.
How can I ensure Ecodan has been installed correctly?
The following items are crucial for a satisfactory installation and your Approved Ecodan Installer should be aware of these:
- Unit Location
- Pipe work Insulation
- Anti Vibration Mounts
- Anti Vibration Connections (flexible hose, supplied loose)
- Consideration in retrofit situations
- Frost Protection of system
- Condensate removal
- See Install manual for full description of these points
How much space do I need for the Ecodan outdoor unit?
Ecodan is approximately 950mm tall by 950mm wide and has a depth of 330mm. Sufficient ventilation space is required at the front of the unit (1m) and at the back of the unit (250mm).
Where does my gas boiler go in the installation?
There is no need to have a gas or oil fired boiler in an Ecodan installation.
Can I put a heat pump in the loft space – can I do this with Ecodan?
Unless the property has been specifically designed to incorporate a heat pump in the loft space we would not recommend this type of installation. A heat pump in heating mode will generate large volumes of very cold air. This could affect the temperature of any enclosed space (unless the heat pump is completely ducted to outside). In addition heat pumps do generate a small amount of vibration. Unless very carefully designed the inclusion of a heat pump in a loft space could cause occupant disturbance. Provision for condensate removal would also have to be made.
What capacity is Ecodan, and what electrical power do I need?
Ecodan can provide 5kW to 14kW of heating load. As it has been designed for the domestic market single phase power is suitable. Come April 2009, a 3-phase system on the 14kW system only will be available.
Will Ecodan work with my existing radiators?
New build properties will have the radiators correctly sized for Ecodan. For retrofit applications in newer homes, existing radiators are likely to be of suitable size and performance to cope with the lower flow temperatures provided from Ecodan. In older homes with older radiators this may not be the case. In all installations Mitsubishi Electric would recommend checking design of all radiators. Before installing Ecodan - additional or larger new radiators may be required.
Do I need low surface temperature radiators?
Low surface temperature radiators are not needed. These radiators work with conventional high temperature systems and the low surface temperature is a safety feature to prevent burns.
What kind of protection do I need for my sanitary hot water?
WRAS (Water Regulation Advisory Scheme) guidelines state that hot water needs to be stored above 60oC and distributed at no less than 55oC to prevent microbial growth (legionella). However, in recommendations it states that hot water should be distributed less than 50oC to avoid risk of scolding. Under G18.5 of the Water Regulations, terminal fittings or communal showers should be supplied through thermostatic mixing valves so water temperatures do not exceed 43oC.
Ecodan has built in controls to perform the prevention of microbial growth (legionella) by weekly boosting the water temperature to over 60oC to sanitise the system, therefore water can be stored at lower temperatures for maximum efficiency.
Are there any special requirements during Winter?
During the cold spell please ensure the correct amount of inhibitor is put in the system to prevent it from freezing.
Recommended inhibitors are Fernox ALPH11 or Sentinel X500
Is it possible to combine radiators and underfloor heating in the same system?
Yes. The water flowing through the radiator circuit will be the same temperature as the water flowing through the underfloor heating circuit.The radiators will need to be sized using the water temperature of the underfloor heating circuit.
Can Ecodan be linked to a solar thermal system to provide 'automatic' switching betweeen the two(e.g. the heat pump will only kick in for hot water generation if the solar is not effective or has raised stored water temperatures as far as it can due to weather conditions)?
Solar thermal can be incorporated into a heat pump system using a twin coil cylinder. The solar output heats the tank during the day leavinfg any difference between actual and desired tank temperature to the heat pumpduring its programmed heat up time. An accumulator can also be used in conjunction with an unvented cylinder, which are popular in solar thermal systems to ensure higher use of energy available.
Can Ecodan be connected to a thermalstore or a buffer store and if not recommended why?
Buffer vessels are normally used with fixed speed compressor heat pumps because of the inefficiencies of the unit in constantly turning fully on and off. Inverter driven compressors such as the Ecodan alleviate the need for such a vessel as they can vary their output between on and off, therefore delivering the output required. Heat pumps can be used in conjunction with thermal stores and many manufacturers produce these with heat pump and solar thermal functionality in mind.
Since Ecodan is so energy efficient it is being classified as a renewable energy source (because it harvests free energy from the air), and you can obtain a grant for installation from the following sources
Because Ecodan's output efficiencies are in the seasonal order of 3 to 3.5 (i.e. 300% to 350%), the actual amount of electrical energy consumed from the national grid is dramatically reduced. So even taking in to account the reduced CO2/kW for gas (0.19) against CO2/kW for electricity (0.43) Ecodan emits far less CO2 than even the highest efficiency condensing gas boiler.
Heating water according to the latest Part L1A and B (section 8 of Domestic Heating Compliance Guide 2006). Efficiency of Ecodan increases the lower the water temperature and the higher the ambient temperature. Typically, Ecodan supplies water to radiators at 45oC and underfloor heating systems at 35oC. Further increases in efficiency are achieved by varying the water temperature in relation to the ambient air temperature. For sanitary hot water Ecodan supplies water at 53oC. Ecodan is unique as it allows you to set different water temperatures for heating and sanitary hot water.
