- How much is a Kensa Compact Heat pump for an avg UK house of approx 160 sqm?
- What sized Kensa Compact Heat Pump would I need?
- How much do the ground arrays cost?
- What about VAT?
- Who can install a Kensa Heat Pump?
- Where can you install a Kensa Heat Pump and how easy is it to install?
- What about the choice between underfloor, radiators or air?
- What about cooling?
- What warranty comes with the Kensa Compact?
- What regular servicing requirements does the Kensa Compact have?
- What about the "slinkies"?
- What are the environmental and energy efficiency benefits of Kensa heat pumps?
- What value for money do Kensa Heat pumps offer?
- What are the unique features of Kensa’s Compact Heat pumps?
- What is happening in other countries with ground source heat pumps?
- Why don’t Kensa recommend Buffer Tanks?
- What is the design life of Kensa Compact heat pumps, and slinky ground arrays?
- Why don’t Kensa heat pumps need supplementary electric heaters, as is used on other heat pumps?
- What about heating DHW (Domestic Hot Water)?
How much is a Kensa Compact Heat pump for an avg UK house of approx 160 sqm?
The 8 kW version is £4,509 + VAT. This will provide an output to connect to your heating distribution system. You will need to connect two Slinkys, each of which needs to be buried in a 40 metre long trench; nominally, the trenches should be at least 5 metres apart, except where they start.
What sized Kensa Compact Heat Pump would I need?
The heat pump is sized to meet the full space heating losses from your building - no larger, and no smaller. The better insulated your house, the smaller the Heat Pump you will require - and the less money it will cost. There are a range of sizes available - see our online price list. We would recommend that you ask your building service professional (builder, architect etc.) what the heat losses are for your home, and be prepared to ask them to substantiate their answers if the figure appears too high.
Be aware that boilers are always substantially oversized - because they are cheap - often by a factor of two; the actual heating requirement for most UK homes is around 6 to 8 kW. You can perform this calculation yourself by calculating the ground floor area of your house and asking your local authority Building Regulations staff to what insulation standard your home was built to, likely to be in the region 70 to 100 watts per square metre.
Sadly, the UK housing stock is a very good example of what happens when a country obtains a glut of very cheap energy - in our case North Sea oil - that means there has been no interest in energy efficiency. Any building which obtained building regulations approval after April 1st 2002 will be a bit better than the usual UK fare of dismal insulation that they allowed before, and you could allow a figure of 50 watts per square metre of peak heating requirement to give you an estimate of the size of Kensa Compact that you will need, (i.e. 160 sq m @ 50 watts per sq m = 8kW). However, this is just a rule-of-thumb which ought to be calculated more accurately by your building services professional.
You may find that it is cheaper to better insulate your building and have a smaller heat pump system - and this is one way that the Kensa Compact tends to put the focus on the overall energy use of a building. UK buildings use well over half the country\’s energy requirements just for heating and cooling - and are therefore the biggest polluters.
How much do the ground arrays cost?
The ground arrays will cost a varying amount between a few hundred pounds for a single DIY Slinky to many thousands if you have less land and opt for boreholes.
VAT is at 5% for domestic ground source heat pumps installed in the UK. Kensa will invoice third-party installers or builders at 17.5%, and they should invoice the homeowner at 5% if they are registered for VAT.
Who can install a Kensa Heat Pump?
Anyone who can install a boiler - although most people use a competent plumber. As there is no combustion, no qualifications are required. Our systems are installed throughout the UK, Ireland, France and other EU countries. As the system is being commissioned, we need the installer to contact us, so that the on-board software diagnostics can be interrogated, to make sure that the system is operating correctly.
Where can you install a Kensa Heat Pump and how easy is it to install?
Heat pumps produce some noise - similar to that of an oil fired boiler. Unlike a boiler, they also produce vibration. For this reason, heat pumps should always be installed away from occupied spaces. The best place is in a utility room, or at the back of a garage. Be aware that noise travels upwards, so noise from a heat pump in a utility room can travel upwards to a bedroom. Bear in mind that heat pumps usually run at night, on off-peak electricity.
What about the choice between underfloor, radiators or air?
Heat pumps should be connected to buildings with a "wet" underfloor heating system throughout - ie. without radiators fitted anywhere. The underfloor systems must consist of pipes buried in deep concrete screed on the ground floor, with the equivalent of at least 100 mm of Celotex or Kingspan underneath. This is because a building should be heated with water at a flow temperature of as little as 30 to 35 degrees C. The better insulated the building, the lower the flow temperature required to the underfloor heating system. The lower the output flow temperature from the heat pump, the higher the efficiency of the heat pump - and the lower the running costs. Be careful using underfloor in inverted houses that have living rooms upstairs. Always tell your underfloor heating system supplier that you are considering using a heat pump, as some companies need to increase the pipe density or pipe diameter.
All new boilers must now be of the energy-saving condensing type, which need a low flow temperature to keep them in condensing mode. So, the same rules apply to boilers as heat pumps.
Radiators can be connected to heat pumps, but it is not recommended. This is because a high flow temperature - of 50 deg C or more - will be required which will cost more energy to run the Heat Pump. It may be that a flow temperature of more than 50 deg C is required, so a heat pump cannot be used. Radiators cause heat pumps to cycle freqently, which means that they start several times per hour, reducing their life and creating disruption on the electricity network.
Ducted air is popular in North America, and can be used effectively in the UK, especially if cooling is required. However, it is not as efficient as under floor, and can be noisy, and the fans use energy. Flow temperatures are generally the same as radiators, with all the same disadvantages.
First of all, if you have a GSHP to give cooling, then you will not be able to claim a grant. All of Kensa’s heat pumps can provide cooling as well as heating - although it costs extra for this option to be factory added; it is not possible to "field fit" the cooling option. It is possible to provide a small amount of cooling using an underfloor heating system, but not generally in houses, as the floor areas are too small. A sohpisticated control system is required to take account of the possibility of condensation. This method of cooling is usually regarded as unsuitable for houses because the floor area is too small and the response time too slow. We would also recommend the use of a buffer tank if you are considering cooling with an underfloor system. Please contact an underfloor heating manufacturer for more details (see our links page).
Cooling adds a great deal of complexity to the internals of a heat pump, and can reduce efficiency and reliability, although not be a significant amount.
Cooling with radiators is not possible.
Cooling with air using fan coils is ideal, and there are some hybrid systems that use under floor heating in the winter and fan coil cooling in the summer, both connected to the heat pump, with a 3 port changeover valve between the two.
What warranty comes with the Kensa Compact?
1-year parts and labour, return to base. Extended warranties are available.
What regular servicing requirements does the Kensa Compact have?
None.
As far as we are aware, we are the only company that manufacture both heat pumps and slinky ground arrays. This means that you can buy a complete "package" from Kensa which is not available from other suppliers. Bear in mind that "imported" heat pumps often have ground arrays supplied by an importer who simply "guesses" what may be needed to match a foreign heat pump with a UK building, in a UK climate...........
Digging in slinkies is easy. A 2 metre deep trench is dug with the narrowest digger bucket, with the trenches kept 5 metres apart from themselves and each other. The slinkies supplied by Kensa are then simply lowered into the trench and backfilled with the soil dug out.
What are the environmental and energy efficiency benefits of Kensa heat pumps?
Heat pumps offer the lowest-carbon emission method of heating any building. Unlike boilers, there is no pollution on-site. As the electricity grid gets cleaner, and more renewable electricity is brought on line, so the carbon emissions from the heat pumps fall. There are no flammable fuels or tanks; no flue, no pilot light and no toxic exhaust gases. There are no road miles from LPG or oil tanker deliveries - serious pollution which is often not considered.
Our heat pumps have no ventilation requirements, and are not precluded from being fitted in any part of a building, although we would always recommend that it be fitted in a utility room, plant room or garage, and away from bedrooms where noise and vibration can be an issue, just like an oil-fired boiler.
The heat pump can be installed so that there is no visible pipe work, and there are no external parts that can be removed, damaged or vandalised.
A heat pump can last up to five times longer than a new boiler and as the essential ingredients are copper and steel, the comparable embodied energy is very, very low.
What value for money do Kensa Heat pumps offer?
In a low energy building over a ten to twenty-five year period, there is a cost benefit over a mains gas-condensing boiler. However, as gas prices rise compared to electricity (which comes from a mix of sources), this time period will reduce. There are also no servicing or maintenance costs.
What are the unique features of Kensa’s Compact Heat pumps?
They are specifically designed to be installed by a plumber or competent DIY without any specialist training.
The Slinky ground arrays are available as matched kits, direct from Kensa. Provided that the slinkies are buried correctly, and the heat pump and slinkies are sized correctly, Kensa offer an unique performance guarantee - that is not available from any other manufacturer or supplier of ground source heat pumps.
Kensa heat pumps are somply better designed than any other ground source heat pump. Their design makes them easier to assemble, which is why they can be priced more competitively than others.
What is happening in other countries with ground source heat pumps?
Not as much as many people think!
In the EU, heat pumps have a share of less than 0.3% of the entire heating appliance market. Even in countries like Sweden, where as many as 40,000 per year are sold, heat pumps are astronomically expensive compared to a mains gas boiler - and must be installed by a specialist installer. The reason that they are so successful in Sweden has little to do with the design or expertise of native heat pump manufacturers - and everything to do with the lack or oil, gas, coal, and even electricity.
There is no large-scale manufacturing of ground source heat pumps anywhere except North America - and 80% of those are designed for cooling, not heating.
In 2004, around 70,000 heat pumps were sold in the EU. In the UK during this period, there were more than 1,000,000 boilers sold, of which more than 100,000 were oil fired. So, the entire EU heat pump market is dwarfed just by oil boilers in the UK. 60,000 of these 70,000 heat pumps have a British made compressor.
So, heat pumps are very much a British technology, rather than Swedish or Continental.
Why don’t Kensa recommend Buffer Tanks?
Please see downloadable Fact Sheet on this topic below.
What is the design life of Kensa Compact heat pumps, and slinky ground arrays?
Kensa Compact heat pumps have a design life of 25 years.
Slinkies have a design life of 100 years, the same as the gas and water main buried in the road.
Why don’t Kensa heat pumps need supplementary electric heaters, as is used on other heat pumps?
Heat pumps should always be sized to meet 100% of the space heating load required by Building Regulations.
Other heat pump brands are not as easy to assemble as Kensa heat pumps, so are often too expensive to allow a large enough heat pump to be afforded. To try to get around this shortcoming, some salesmen may try to part-size the heat pump, and offer the balance of heat from direct electric heating. This will give much higher energy bills, and emit a lot more pollution and carbon - pretty obvious really!
You don\’t expect your car to have an engine sized at 80% of the required size -so why should your building be any different.......
What about heating DHW (Domestic Hot Water)?
This is best achieved with solar panels. It is cheaper to use off-peak electricity and an immersion heater than to use oil to heat DHW. Please see the Fact Sheet download below for more information on this topic.