Mark Group

Heat Pumps Frequently Asked Questions

What are Heat Pumps?

Heat Pumps, like fridges and freezers, are just units that move heat energy from one place to another.

A fridge moves heat from inside its box to outside, whereas Heat Pumps harvest ‘low grade heat’ from the ambient environment (Air,Water or Ground) and convert it into useful ‘high grade heat’ for use in the home.

This conversion is performed by a compressor-driven refrigeration cycle which consumes electricity in the process. This process is very energy efficient however, with heat pumps producing significantly more energy in heat than they consume in electricity.

This efficiency is measured by a figure called the Coefficient of Performance (CoP), and is typically in the range 2.5 – 4. This advanced heating technology used in heat pumps make them ideal for use in the UK’s ambient temperatures and hence perfect for the domestic market.

What are the benefits of Heat Pumps?

• Low running costs
• Significant savings compared to other forms of heating (Oil, Gas, Electric, LPG)
• 30 – 50% reduction in CO2 emissions
• Consistent comfortable heating levels maintained
• Can be installed with underfloor heating or radiators
• Low maintenance requirements
• No gas supply, flues or ventilation required Air Source Heat Pumps only
• Straightforward installation – self contained unit only requiring water and electric connections

• No groundworks or external pumps required

Is it suitable for my home?

Heat pumps, if sized correctly, can cover the heating and hot water requirements of most properties. However, it is essential that your home is well insulated and draught-proofed as heat pumps operate at lower flow temperatures than traditional boilers.

Heat pumps are a particularly viable option where gas is unavailable. The type of heating being replaced (electricity, oil, LPG or coal) will contribute directly to potential savings.

The heat pump unit will need space outside the house and your hot water storage cylinder is likely to be replaced.

Ground source systems also require heat collector pipes to be installed underground. This typically requires a significant garden area for horizontal trenches or vertical boreholes.

Heat is then delivered through your heat distribution system. This can be radiators and/or underfloor heating but must be decided before installation so that the heat pump system can be sized correctly.

If you want to further reduce your home’s CO2 emissions you can sign up to a green electricity tariff or install some form of renewable electricity generation on your home to provide power to the heat pump.

Is the work checked/tested?

Your system will be fully tested before we leave

What are the typical costs of installing a Heat Pump

The costs of installing Heat Pump systems vary depending on the type, size and manufacturer of the system to be used.

There are decisions to be made over the heat source, ground or air, single or split unit heat pump and the amount of heat to be delivered through either radiators, an underfloor heating system or both.

Typical domestic heat requirements will be in the 5-10kW range but will vary with house type and the level of insulation fitted. An air source heat pump system could be installed for £6,000 – £8,500.

The additional groundwork costs required to fit the heat collector for a ground source heat pump depend on the type of collector (slinky pipe or borehole etc.) and the local ground/geology. However typical domestic systems are likely to be around £10,000 – £20,000.

Do I need planning permission?

The Government has recently passed a “permitted development” order allowing certain microgeneration technologies to be fast-tracked through planning systems, However some local authorities still require additional details to allow you to fit a Heat Pump System, especially in conservation areas or on listed buildings.

Always check with your local authority about planning issues before you have a system installed. Obtaining retrospective planning permission can be difficult and costly.

Do I have to do anything before the installation?

No, apart from seeking approval from your local planning authority, if required.

Do the installers have to come into the house?

The technicians must have access to the inside and outside of your property. In particular the distribution board, airing cupboard and loft, in order to complete the installation process.

Is there much mess?

No, dust sheets will be laid throughout the house to minimise any dust or debris, and our technicians will thoroughly clear up before they leave.

How long does it take?

A typical installation should take approximately three to five days to complete.Work will take place both inside and outside the property in this time, and includes the installation of pipework and electrical cabling and the commissioning of both the hot water and heating systems.

However, work could be delayed due to inclement weather.We will endeavor to keep to our schedule where possible but will keep you informed of any changes.

Do I need to provide anything?

No, our installation team provide all of their own equipment including lights, ladders and relevant lifting equipment.

What is the life span of the system?

Heat pumps will last typically between 10-25 years.

Is the system guaranteed?

All our products come with manufacturer guarantees.

In addition to the manufacturer’s backed guarantee, which covers the equipment, you will receive a guarantee for the installation from REIGA (Renewable Energy Installation Guarantee Agency). This is an independent guarantee which is valid for a period of 10 years and is applied for by us on your behalf. It will be sent to you direct from REIGA and can take up to 8 weeks from installation to be delivered.

REIGA is an independent non-profit guarantee agency. Its only function is to stand as guarantor for the promises set out in the guarantee. It has all the resources to meet the promises made in the guarantee.

For further information see www.reiga.org.uk

Are there any maintenance or servicing requirements?

Any glycol in the system will require changing every 3-7 years, and the hot water cylinder will require a standard service check each year if an unvented system is installed.

How does it work?

The technology inside the heat pump is similar to any domestic refrigerator, which uses a vapour compression cycle.

The main components in the heat pump are the compressor, the expansion valve and two heat exchangers (an evaporator and a condenser).

1. Refrigerant in the evaporator is colder than the heat source. This causes the heat to move from the heat source (in this case the outside air) to the refrigerant, which then evaporates.
2. This vapour moves to the compressor and reaches a higher temperature and pressure.
3. The hot vapour now enters the condenser and gives off heat as it condenses.

1. The refrigerant then moves to the expansion valve; drops in temperature and pressure; and then returns to the evaporator.

If I have any further queries before/after the installation - what should I do?

Please contact us at any time to discuss any queries. Most can be answered swiftly and efficiently so please do not hesitate to speak to a member of our renewables operations team.