frequently asked questions
What are heat pumps?
Which heat pump is best for me?
Water source
Ground source
What are the main benefits of heat pumps?
What are the energy savings benefits?
What are the benefits in CO2 emissions and why are they important?
What are the proven cost savings?
How easy is it to install?
What can heat pumps be used for?
SOLAR FAQ’s
What is solar power and what does it do?
How does solar technology work?
What is the environmental and financial case for solar technology?
How long do the panels last?
How easy are they to install?
What are the different types of panel available and what are the key benefits of each?
UNDER-FLOOR HEATING FAQ’s
What floor types can accommodate under-floor heating?
Can rooms have individually controlled temperatures?
What powers the under-floor heating?
Is there any risk of over-heating?
What energy savings can be expected?
How easy is it to install?
How do I know which system is best for me?
Why consider air conditioning in the first place?
How does air conditioning work?
What are the different air conditioning systems available?
How easy is it to install?
What is the environmental case for air conditioning?
What are the core benefits of air conditioning?
Why is ventilation so important?
How can I maintain good ventilation and minimize heat loss?
How do Heat Recovery units work?
What if I don’t have a roof space?
What about in Summer, when warm air is the last thing you need?
What are the key benefits of a Heat Recovery system?
COST SAVINGS FAQ’s
Heat Pumps cost less to run than conventional heating systems
For every 1 KW of energy or equivalent supplied to a Gas, LPG or Oil Boiler, less than 1 KW is transferred into usable heat. Whereas with a Heat Pump, for every 1 KW of energy supplied, between 2.5 & 4.5 KWs of usable energy is available for heating.
Nearly all heat pumps use electricity to drive them. Until recently gas has been cheaper, but with the significant and ongoing rise in gas prices heat pumps have become a viable option. Using a percentage of cheaper "off-peak" electricity has made heat pumps even more attractive.
For example for every 1 KWH of heating:-
| Gas Boiler costs |
3.8 pence |
| LPG Boiler costs |
6.4 pence |
| Oil Boiler costs |
7.0 pence |
| Heat Pump with COP of 3.5 costs |
3.1 pence |
| Heat Pump with COP of 4.5 costs |
2.4 pence |
| Heat Pump with COP of 3.5 & 50% Off Peak Electricity costs |
2.4 pence |
| Heat Pump with COP of 4.5 & 50% Off Peak Electricity costs |
1.8 pence |
These costs are for guidance: actual prices depend on your supplier, gas & electricity tariff selected and mix of Standard & Off Peak Electricity used.
When Heat Pumps are used to heat a building, a substantial reduction in CO2 emissions and reduced running costs are achieved compared to traditional heating systems.
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REDUCED ENERGY FAQ’s
Heat Pumps use less energy than conventional heating systems
For every 1 kW of energy or equivalent supplied to a heat pump 2.5 & 4.5 kWs of usable energy is available for heating, whereas with Gas, LPG, Oil Boiler or Electricity less than 1kW is available for heating.
Modern Heat Pumps can provide seasonal Co-efficients Of Performance (COP’s) in excess of 4.5
Current Building Regulations acknowledge the benefits of heat pump technology.
| Heat Pumps (SAP 2005) |
Efficiency%
|
| Ground to air heat pump (powered by electricity) |
320
|
| Ground to air heat pump with auxiliary heater (powered by electricity) |
300 |
| Water to air heat pump (powered by electricity) |
300 |
| Air to air heat pump (powered by electricity) |
250 |
| Gas-fired, ground or water source |
120 |
| Gas fired, air source |
110 |
| Gas water heater (direct no tank) |
70 |
When Heat Pumps are used to heat a building a substantial reduction in CO2 emissions and reduced running costs are achieved compared to traditional heating systems.
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REDUCED CO2
Heat Pumps have fewer CO2 emissions than conventional heating systems
For every 1 KW of energy or equivalent supplied to a Gas, LPG or Oil Boiler, less than 1 KW is transferred into usable heat. Whereas with a Heat Pump, for every 1 KW of energy supplied, between 2.5 & 4.5 KWs of usable is available for heating.
Example.
For every 1 KWH of heating:-
| Gas Boilers produce |
250 grams of CO2 |
| LPG Boilers produce |
300 grams of CO2 |
| Oil Boilers produce |
350 grams of CO2 |
| Heat Pumps with COP of 3.5 produce |
150 grams of CO2 |
| Heat Pumps with COP of 4.5 produce |
100 grams of CO2 |
HEAT PUMP FAQ’s
What are heat pumps?
All around us are sources of stored solar energy, which even at relatively low temperatures can provide us with heat to power heating, cooling and ventilating systems that can keep buildings at a comfortable temperature – heating in Winter, cooling in Summer and ventilating all year round.
Heat pumps upgrade naturally occurring low temperature heat to useful high temperature heat and vice versa, to provide both heating and cooling.
The technology involves equipment which transfers energy from one location – the earth, water or the air – to a pump that extracts heat and converts it into a complete climate control system.
Heat Pumps offer considerable energy savings resulting in lower CO2 emissions and reduced energy costs
How a Heat Pump Works
1. Indoor unit: a fan draws hot air over a heat-exchanging coil, through which cold refrigerant flows. This absorbs the heat from the air and cooled air is blown into the room.
2. Pipe work: the refrigerant circulates through the units and takes the heat from the indoor unit to the outdoor one.
3. Outdoor unit: the refrigerant gas passes through a heat exchanger and the heat absorbed from the Indoor Unit is dissipated with the aid of a fan. This process cools the refrigerant which becomes a liquid, this liquid is pushed through a compressor into the Indoor Unit where the process starts again.
Why invest in heat pumps in the first place?
Heat pumps provide natural energy from the earth’s resources at a fraction of the cost of traditional methods. Whether you install a ground, water or air based heat pump, energy efficiency is typically 400% compared to traditional boilers at 70-95%, and without the need for gas or oil to fuel your heat generation, cost savings are enormous.
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Which heat pump is best for me?
The choice of heat pumps in any given location depends on access to natural heat sources around it.
Water source heat pumps are best, if you have access to a local water source such as lake, river, reservoir or underground water course, because of the ease of transferring and conducting heat. Plastic piping is laid in the water and, with minimal digging, water can be directed through the heat pump for the necessary heat to be extracted.
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Ground source heat pumps are next best if no suitable water source is available, with bore holes drilled into the surrounding ground and collector pipes inserted to collect the ambient heat from the ground, which is typically at a constant 10-15 degrees, whatever the season or weather. This is sufficient to power a heat pump and give you year-round heating, cooling and ventilating.
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Air source heat pumps are used when no access to ground or water is available (flats, apartments, inner city dwellings etc), whereby heat is extracted from the air. These have a wide operating temperature range and can be used with an auxiliary heating system to produce low-carbon, energy-efficient heating and cooling.
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What are the main benefits of heat pumps?
- No need for an oil or gas boiler
- Provides all your heating and hot water needs
- Save up to 70-85% in energy costs against conventional systems
- Fewer CO2 emissions
- For every 1 unit of electricity used, an average of 4 units of heat are produced, meaning 75% of your energy comes from your own power plant.
- 20+ year’s system lifetime and no annual maintenance
- No risk of explosion or carbon monoxide poisoning
- No need for gas connections or fuel tanks
- Can be used with under-floor heating, radiators, fan coils or a combination
- Will heat swimming pools
- Energy efficiency 300-400% versus boilers at 70-95%; plus efficiency is maintained over their lifetime, while boilers deteriorate
- Cooling as well as heating possible
- Available whatever the season or weather
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What are the energy savings benefits?
Typically traditional heating systems are notoriously inefficient:
- Power stations require 1kW of energy to output 0.4kW (40% efficiency)
- There are further significant losses in transmission round the country
- The average central heating boiler operates at between 70 and 95% efficiency (1kW in = 0.7-0.95kW out)
- By simply transferring heat from the environment (air, ground, water) into a building, a heat pump will use only 1kW of energy to extract 3kW of heat (300% efficiency)
- When you take into account power station and electricity transmission losses, heat pumps are up to 5 times more efficient at producing energy that can be used for either heating or cooling.
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What are the benefits in CO2 emissions and why are they important?
Carbon dioxide is thought to be a major contributor to global warming, and anything we can do to minimise man-made emissions will have long-term benefits for the planet.
The chart below shows comparative CO2 emissions for conventional boilers and heat pumps with COP (Co-efficient of Performance) of 3.5 and 4.5.
For every 1kW of heating:
| Gas boilers produce |
250g of CO2 |
| LPG boilers produce |
300g of CO2 |
| Oil boilers produce |
350g of CO2 |
| Heat pump with COP of 3.5 produces |
150g of CO2 |
| Heat pump with COP of 4.5 produces |
100g of CO2 |
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What are the proven cost savings?
For every 1 KW of energy or equivalent supplied to a gas, LPG or oil boiler, less than 1 KW is transferred into usable heat. Whereas with a heat pump, for every 1 KW of energy supplied, between 2.5 & 4.5 KWs of usable energy is available for heating.
Nearly all heat pumps use electricity to drive them. Until recently gas has been cheaper, but with the significant and ongoing rise in gas prices heat pumps have become a viable option. Using a percentage of cheaper "off-peak" electricity has made heat pumps even more attractive.
For example, for every 1 KWH of heating:-
| Gas Boiler costs |
3.8 pence |
| LPG Boiler costs |
6.4 pence |
| Oil Boiler costs |
7.0 pence |
| Heat Pump with COP of 3.5 costs |
3.1 pence |
| Heat Pump with COP of 4.5 costs |
2.4 pence
|
| Heat Pump with COP of 3.5 & 50% Off Peak Electricity costs |
2.4 pence |
| Heat Pump with COP of 4.5 & 50% Off Peak Electricity costs |
1.8 pence |
These costs are for guidance, actual prices depend on your supplier, gas & electricity tariff selected and mix of Standard & Off Peak Electricity used.
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How easy is it to install?
After an initial survey, we do a calculation based on the heating and cooling load requirements for your building, and then design a fully costed system based on those projections. Once you accept our recommendations, ground works and installation for a typical 4-bedroom house take between 2 and 5 days. The ground-works usually run in conjunction with internal plumbing and electrical work.
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What can heat pumps be used for?
Virtually any application that requires climate control in any building: heating, air conditioning, hot water, ventilating, air purification, dehumidification, swimming pool heating.
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SOLAR FAQ’s
What is solar power and what does it do?
Via panels mounted (usually) on your roof, solar technology converts the radiation from the sun into hot water, which is then piped into your water storage system – normally the hot water tank.
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How does solar technology work?
Within the solar panels are tubes that contain a fluid, which collects energy from the sun’s rays and then transfers it in the form of heat to water circulating through the panels. That water is then channeled into the building’s hot water system, where it can be augmented and complemented by heat from other generating sources, such as heat pumps, conventional boilers or traditional immersion heaters.
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What is the environmental and financial case for solar technology?
Once installed, the only power needed to run the system is electricity to drive the pump, which is minimal. The heat generated is free.
Since it can provide between 50-70% of annual domestic hot water requirements, the power generation savings are considerable, whether you use gas, oil or electricity for the purpose. Given global energy price trends, those savings are set to grow substantially in the future.
Perhaps even more importantly, in the event of power shortages, it makes you less reliant on traditional energy suppliers.
Indeed, linked to heat pump technology, you can become almost self-sufficient.
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How long do the panels last?
Products are improving all the time, but most already come with at least a 25-year warranty.
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How easy are they to install?
Mounting panels on your roof and running pipe-work to interconnect with an existing system can take as little as a couple of days.
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What are the different types of panel available and what are the key benefits of each?
Tube collectors have glass tubes containing heat-collecting fluid within them, that then transfers the heat to water circulating through them.
Flat plate collectors are based on a copper grid inside the insulated panel to absorb and transfer the solar energy to circulating water in the form of heat.
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UNDER-FLOOR HEATING FAQ’s
What floor types can accommodate under-floor heating?
Virtually any type of floor can accommodate an under-floor heating system: carpets, tiles, wood, laminate or concrete.
If you are starting from scratch and laying a solid concrete or screeded floor, the plastic pipe-work is laid out and permanently embedded in the solid floor, with insulation directly beneath the pipe-work to minimize heat loss.
If you already have a solid concrete floor and do not want to dig it up, we can in™stall a floating floor on the top, incorporating under-floor heating pipes pressed in to high-density polystyrene sheet with pre-formed pipe grooves in. The floating floor system is then covered with chipboard sheeting. This can be used on all floor coverings – not just concrete. Total depth usually: circa 25mm + floor covering.
An alternative for existing solid or timber floors is a low-profile panel system, overlaid on the existing surface with panels glued together, 12mm pipe-work laid in the grooves and then the whole is covered by tiles, laminate, or a plywood capping layer for vinyl or carpet. This is perfect for single-room refurbishments or where available wall space is limited.
For timber and other forms of suspended floor, the pipe-work is laid out along joists or on cross-battens, with insulation in the void beneath the pipe-work, and then standard tongue-and groove flooring is laid on top.
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Can rooms have individually controlled temperatures?
Yes. Programmable room thermostats, connected via valve actuators to a master wiring system, allow you to vary the temperature, room by room.
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What powers the under-floor heating?
You can link it to any available heating system, from electricity through gas/oil-fired boilers, to modern state-of-the-art heat pumps.
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Is there any risk of over-heating?
None whatsoever. Indeed some systems automatically adjust their heat output to compensate for colder areas, such as windows and doors, and warmer areas under rugs and furniture.
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What energy savings can be expected?
The thermal insulation minimizes heat loss and can provide extra energy savings of 20% or more. Linked to heat pump technology, this figure increases dramatically.
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How easy is it to install?
Depending on which system you choose and what existing flooring is in place, once you approve our recommended solution, it usually takes between 1 and 5 days to install and make good, ready for your chosen floor covering to be laid on top.
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How do I know which system is best for me?
Ask GLE to come and do a FREE site survey. We will tell you what your options are and the implications of each – practical and budgetary – before submitting recommendations and fully costed specifications.
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AIR COOLING FAQ’s
Why consider air conditioning in the first place?
Everyone associates air conditioning with cooling in warm temperatures, but systems can equally be used for heating, ventilating, purifying and dehumidifying, if used in conjunction with heat pump technology.
With air conditioning, you can create the climate in which you feel best, with the right temperature and humidity. Modern air conditioners produce clean, healthy fresh air, dehumidify the air and prevent mould, noiselessly and draught-free.
And because you feel better, you become more active, fitter, more creative and productive. There is a proven correlation between an operative’s personal performance and the temperature of his/her immediate surroundings. Indeed accidents tend to occur more frequently at extreme temperatures, and mental performance declines sharply when it is too hot.
There are other health benefits too: air conditioning systems contain filters that remove dust, smoke, bacteria, viruses, mould, fungus, mildew and the like, with major benefits for hay-fever, asthma and other allergy sufferers.
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How does air conditioning work?
The principle of air conditioning is that energy is absorbed in one place and released in another.
The process requires an indoor unit, an outdoor unit, and piping to connect the two. Through the piping, a refrigerant flows from one unit to another, absorbing the energy at one end and releasing it at the other.
1. Indoor unit: a fan draws hot air over a heat-exchanging coil, through which cold refrigerant flows. This absorbs the heat from the air and cooled air is blown into the room.
2. Pipe work: the refrigerant circulates through the units and takes the heat from the indoor unit to the outdoor one.
3. Outdoor unit: the refrigerant gas passes through a heat exchanger and the heat absorbed from the Indoor Unit is dissipated with the aid of a fan. This process cools the refrigerant which becomes a liquid, this liquid is pushed through a compressor into the Indoor Unit where the process starts again.
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What different air conditioning systems are available?
For single room solutions, you will need a split system, with an outside unit, which can be wall- or roof-mounted or floor-standing, linked to an indoor unit that can be equally wall- or ceiling-mounted or floor standing.
Where whole buildings are involved, one or more (depending on the size of the installation) outside units are linked to cassette units in each room, often ceiling mounted. There are units available for installation in false ceilings, and 4-way blow units can be selected.
Larger installations, involving more than four rooms minimum – especially commercial applications, such as shops, offices, factories, warehouses, hotels, cinemas and restaurants usually require a VRV/VRF (Variant Refrigerant Flow) system, typically mounted on an outside roof-top.
Modern VRV systems allow up to 64 indoor units to be connected to one outdoor unit and can be combined with equally sophisticated heat recovery systems.
Used in conjunction with heat pump technology, air conditioning can be emission free and cheap to run, because no fossil fuels are required to run the system, apart from electricity to drive the pumps.
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How easy is it to install?
Obviously it depends on the complexity of the installation and size of the building, but single-room applications can take less than a day, while an average 4-bedroom detached house, with units in every room, would probably take less than a week.
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What is the environmental case for air conditioning?
If you install air conditioning in conjunction with a heat pump system, it allows you to use natural resources to heat and cool the same unit, with significant energy and cost-saving implications throughout the year.
Because they are so much more energy efficient than all conventional heating methods (up to 5 times more), transferring heat from one environment to another via refrigerant, there are proven efficiency gains of the order of 3:1 compared to, say, electrical heating. With all energy prices rising, this benefit is likely to increase significantly in the foreseeable future.
For every unit of energy consumed by a heat pump, three or more units of heat are gained, even on the coldest winter days.
And these technological, environmental and economic benefits apply equally to industrial, commercial and domestic premises.
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What are the core benefits of air conditioning?
- Greater year-round comfort
- Better health: removal of allergens and pollutants
- Better operative performance
- Greater longevity and better performance of indoor equipment
- Fewer accidents in ambient temperatures
- Prevents humidity problems such as mould and mildew
- Can be linked to heat pump technology for energy efficiency and cost benefits
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VENTILATION AND HEAT RECOVERY FAQ’s
Why is ventilation so important?
Modern, well-insulated homes with central heating suffer air pollution up to 10 times worse than outside, according to a “Which” report. Poor ventilation leads to an increased risk of in the atmosphere of allergens, bacteria, viruses, smoke, mould, mildew, fungus and gases, all of which are injurious to health and depress personal performance.
Carbon dioxide levels are often at dangerous health levels too as a result of which, current building regulations require extractor fans in wet areas (kitchen, bathroom, utility, en-suite) with trickle vents in windows, to allow air back in.
Unfortunately this inevitably leads to considerable heat loss.
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How can I maintain good ventilation and minimize heat loss?
The solution is to install a heat recovery system, which retains the heat in the building, extracts it from existing air (which it then expels into the atmosphere), injects it into fresh air from outside, and then re-circulates it.
In this way, you can change all the air in a property every two hours, continually replacing stale, damp air with fresh, filtered warm air, with minimal heat loss.
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How do Heat Recovery units work?
Usually sited in the roof space, and connected to individual rooms via ducting, the unit sucks stale air out and recovers two-thirds of the warmth through a cross-flow heat exchanger.
Fresh air brought in from the outside through a separate grille then passes through the heat exchanger and picks up the warmth, before being circulated through the building. There is no mixing of air flows: all that is transferred is the heat.
The heat exchanger also incorporates a filter to trap pollens and other allergens.
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What if I don’t have a roof space?
There are products available that can be fitted in cooker hoods, and others that can be wall-mounted. There will almost certainly be a product that is right for you.
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What about in summer, when warm air is the last thing you need?
A by-pass block can be incorporated to allow air-flow without heat exchange, so that warm, stale air is expelled and fresh air from outside circulated.
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What are the key benefits of a Heat Recovery system?
- British Allergy approved filtered fresh air – alleviating asthma and hay fever sufferers.
- Very quiet operation
- Excellent heat recovery leading to enhanced energy efficiency
- 1 electrical connection and low voltage control panel
- Constant change of air without draughts
- No unsightly trickle ventilators
- No noisy extractor fans
- Condensation control
- Easy to install
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