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Kensa Shoebox ground source heat pump review
We review the Kensa Shoebox, one of the smallest but best performing ground source heat pumps in the UK.
The Kensa Shoebox is one of the smallest ground source heat pumps in the UK (image credit: Kensa)
The Kensa Shoebox range of ground source heat pumps is produced in the UK. They are among the quietest and most compact ground source heat pumps on the market, providing both heating and hot water for domestic use.
There are two models available in the Kensa Shoebox range: a single compressor model of 3kW and a twin compressor model of 6kW. The Shoebox is small enough to fit under a kitchen sink or inside an airing cupboard, making it a perfect solution for people living in flats.
The size of the Kensa Shoebox makes it incredibly easy to install and service. Fewer boreholes need to be dug, which makes installation much quicker than other ground source heat pumps.
The Kensa Shoebox packs a pretty good punch for its diminutive size, producing hot water temperatures of up to 65°C and can be configured to deliver passive cooling in warmer months. Noise levels are extremely low at fewer than 52 decibels, making it nearly imperceptible to homeowners.
The Kensa Shoebox fits easily inside a cabinet or airing cupboard, generating hot water temperatures of up to 65°C. It uses non-flammable refrigerant for added safety and noise levels are at a nearly indiscernible 47-52 decibels.
Guarantee options: Standard 5 years, plus technical support for the life of the pump
Price range: 3kW model from £4,055; 6kW model from £5,429
Max power: 6kW
Highlights: Kensa offers a number of flexible funding options for the Shoebox range, including support from various government and green energy schemes.
Key benefit: The Kensa Shoebox is incredibly compact, quiet and affordable.
Maximum flow temperature: 65°C.
Noise level: 47-52 decibels.
Dimensions: 515mm (h) x 480mm (w) x 360mm (d) for the 3kW unit; 585mm (h) x 610mm (w) x 595mm (d) for the 6kW unit
If you’re interested in purchasing a ground source heat pump for your home, there are several benefits to the Kensa Shoebox that can’t be ignored, including:
Easy installation: The Kensa Shoebox is light and compact, making it easier and far cheaper to install. Fewer boreholes need to be dug, which also shortens your installation time.
Safety: The Kensa Shoebox uses non-flammable refrigerant, which makes it a safer and less expensive option for flat-dwellers than fossil fuel-based systems.
Compatibility with district heating schemes: A single Kensa Shoebox can be installed per dwelling for independent heating and billing. Large-scale installations qualify for project management and tenant liaison support from Kensa Contracting.
Size: The Kensa Shoebox is small enough to fit inside a kitchen cabinet.
Cooling: The Kensa Shoebox comes with a passive cooling system to cool your home during hotter months.
Quiet: The Kensa Shoebox is exceptionally quiet, making no more noise than a standard fridge or freezer.
Servicing: Unlike many other ground source heat pumps, there is no need to service the Kensa Shoebox annually.
There are a few disadvantages to consider:
Output: At 6kW, the output of the Kensa is low and really only suitable for small homes.
Warranty: The Kensa Shoebox is only guaranteed for five years; however, Kensa offers technical support for the entire lifetime of your heat pump.
How does the Kensa Shoebox ground source heat pump work?
The Kensa Shoebox comes with 22mm valve connections on top of the heat pump with flexible pipes for easy installation inside a kitchen or airing cupboard. There is an in-built water pump for the ground side of the Shoebox unit.
A fixed speed compressor compresses the ground’s low-grade heat in a highly efficient manner. Weather compression will adjust the heat pump’s temperature depending on the weather.
There are two temperature setpoints for heating and hot water to produce the required heat at the highest efficiency, eliminating the need for expensive direct immersion heaters.
The Kensa Shoebox is not only small, it’s effective (image credit: Kensa)
How does the Kensa Shoebox ground source heat pump compare to other heat pumps?
It’s hard to compare the Kensa Shoebox to other ground source heat pumps on the market because it was designed specifically for use in flats or other small spaces and there are no direct competitors in this niche (so far). If you have a larger home, you’re probably better off considering some of the alternatives on the market.
Kensa’s Evo range is still fairly compact and offers an A+++ efficiency rating to boot. The output is larger than the Shoebox range, from 7kW all the way up to 17kW. Its maximum flow temperature matches the Shoebox at 65°C.
You may also want to look at Worcester-Bosch’s Greenstore LECP range. It’s slightly more expensive than the Kensa Evo or Kensa Shoebox, but still highly efficient. The Worcester-Bosch Greenstore LECP comes with its own water cylinder with a 185-litre capacity so that hot water is readily available on demand.
If you have a larger home and want even more power than the Worcester-Bosh or Kenso range can provide, the Viessmann Vitocal 350-G is highly recommended as one of the most powerful ground source heat pumps on the market. It offers single-stage heating outputs of 20.5-42.3kW with maximum flow temperatures of up to 70°C. It’s more expensive than the alternatives, but probably the best bet if you need to heat a large space.
What does the Kensa Shoebox ground source heat pump cost?
The Kensa Shoebox is one of the most affordable ground source heat pumps available in the UK today. Here’s how it compares to other units:
Cost (excluding installation and labour)
Worcester-Bosch Greenstore LECP
Viessmann Vitocal 350-G
Maintaining the Kensa Shoebox
The Kensa Shoebox is extremely straightforward to use and maintain and does not require annual servicing. However, it’s a good idea to include a water treatment device in hard water areas to protect your unit.
You should also keep an eye on the console for flashing error codes, indicating issues with the heat pump. This could include:
TP: Low water pressure.
HP: High gas pressure caused by low or no flow on the heating distribution circuit.
LP: Low gas pressure fault.
A1: Antifreeze alarm indicating that the ground is too cold, that insufficient antifreeze is present or that the unit wasn’t commissioned correctly.
If any of these codes pop up, call the Kensa Technical Department. While the unit warranty expires after five years, the company offers lifelong technical support.
What the professionals say
“This innovative technology has already proved successful and is something we are looking to expand in the future.”
“The new homes are excellent examples of great design and the embodiment of modern technology to ensure they sit well with the local character and tradition. The properties include ground source heat pumps that will provide both heating and hot water from a sustainable source, which the occupier and the society will benefit from in the long term with reduced energy bills and happy tenants. Kensa Contracting were involved from an early stage to advise on initial feasibility, viability, technical matters and costings. This included various meetings and presentations to the client and project team to ensure that all were familiar and comfortable with the system proposals. Kensa continued to offer an excellent service throughout the building programme including the onsite borehole installations and ensuring that the Shoebox heat pumps were correctly installed and commissioned by our plumbing and electrical contractors.”
Paul Davies, Senior Surveyor at developers of Tuckers Close, E G Carter & Co Ltd
“We found working with Kensa to be an excellent, positive experience, from the initial design stages through installation, commissioning and completion. Although the site was quite constrained, with limited space available on-site, Kensa’s installation team arrived on schedule and completed the installation, working with our site manager to minimise any disruption and delay to our construction programme.”
“We are delighted with the support we have received from Jordan on the Tech Support Team (Truro). I know nothing about technology and yet he carefully guided me through some queries we had about our newly installed ground source heat pump. He was very patient as he guided me as I navigated the control panel. It has given us enormous confidence in the Kensa team and I know that no question is either too silly or too small. Thank you!”
“Have had a heat pump supplied by Kensa since our house was built 14 years ago. It has been absolutely excellent. Extremely economical, without any servicing issues. A recent problem occurred when a capacitor failed. Technical support was immediate ( they replied to my enquiry within one hour ). They supplied the necessary replacement part overnight. Special thanks to Carl (K? ) who was particularly knowledgeable, and helpful and even telephoned to check that the repair had gone well. Can not praise him and Kensa enough. Definitely, the best customer service we’ve ever experienced. Many thanks, Carl.”
“Great company and GSHP. After nearly 8 years of continuous operation, our trusty heat pump developed a fault. I called Kensa technical support services and despite having very little experience in this area was patiently talked through the investigation by Carl Jackaman until we had successfully diagnosed the fault. After fitting the required part, everything is now up and running again and I can not speak highly enough of their technical support services.”
Its size and efficiency make the Kenso Shoebox the perfect ground source heat pump for new builds, small flats or first-time homeowners that want to slash their heating bills on a budget. They have a trusted network of contractors that can be relied upon for a number of installation projects. Large-scale projects receive additional support while all customers can rely on Kenso for technical support and advice for life.
All in all, the Kenso Shoebox is a great heat pump. While it’s not suitable for a larger home, it’s the perfect solution for homeowners with limited space and a limited budget.
We know how important and expensive a heat pump system can be. When compiling this review, we read thousands of in-depth customer reviews (Google, Trustpilot and forums), sought professional opinions, read media articles and consulted professional reports to provide a score out of 100 points for the Kensa Shoebox.
The points were compiled as follows:
The warranty period offered by the brand, for a total of 10 points;
The overall reputation of the brand is based on online reviews, for a total of 15 points;
Trustpilot reviews, for a total of 5 points;
Awards and accolades (e.g. Which? Best Buy Awards) for a total of 5 points;
Customer service performance, for a total of 10 points;
The price range, for a total of 15 points;
Efficiency ratings, for a total of 15 points;
Installation and maintenance network and reviews, for a total of 15 points; and
The total warranty period for a total of 10 points.