Your free home assessment
James visits, gives a straight answer on suitability and a fixed estimate on the spot.
The average air source heat pump cost in Devon sits at about £15,000 gross, before any grant is applied. Take the Boiler Upgrade Scheme off that and most homeowners settle close to £7,500, while off-gas-grid properties on the higher oil and LPG rate land lower still. Use that figure for planning. The real figure for your property comes out of a room-by-room heat loss survey, and anyone quoting a fixed price down the phone without seeing the house is guessing.
Key Takeaways
- Budget about £15,000 gross for a typical Devon installation, with most homeowners settling close to £7,500 once the grant has been taken off.
- Off-gas-grid Devon homes replacing oil or LPG can qualify for £9,000 through the Boiler Upgrade Scheme, and that higher rate runs to 31 March 2027.
- An eligible off-grid oil or LPG home pays £6,000 on a £15,000 installation at the £9,000 rate, deducted upfront on applications up to 31 March 2027.
- Your number moves with property size, radiator changes, cylinder siting and electrical work far more than with the badge on the outdoor unit.
- There is 0% VAT on qualifying work until 31 March 2027, and nothing extra to apply for.
- The £250 plus VAT heat loss survey produces your fixed price and is deducted in full on installation.
Two things decide where your own figure lands: what the building needs, measured room by room, and which grant rate your home qualifies for. A “from £X” headline skips both, which is why it collapses the moment somebody measures a room.
What Is the Average Air Source Heat Pump Cost in Devon in 2026?
Carry £15,000 in your head as the gross figure, before any grant comes off. It matches the figure on our air source heat pump installation page, and it works as a range-finder until somebody has measured your rooms.
£15,000
A range-finder for planning. Your own figure comes from the survey.
What that figure covers
- The heat pump, sized to the measured heat loss of your rooms
- A heat-pump-specific, pre-plumbed hot water cylinder
- The pipework and electrical work the design calls for
- Commissioning, then handover once the system is running
Two properties that look almost identical from the road can price several thousand pounds apart: a 1970s bungalow near Woodbury and a stone-built property outside Ottery St Mary. Neither figure is wrong; one building asks for more pipe, more labour and more emitter.
Why the price can stay fixed after the survey
The Ideal Logic Air is the range we fit most often in Devon. James still picks the unit and cylinder for each property from its own heat loss figures, and those figures often lead to the Ideal.
4 to 10 kW
Typical size. Where the measured heat loss of ordinary Devon detached houses and bungalows tends to land.
Its cylinder arrives assembled from the factory, so the hours a job will take are known before anyone starts, and predictable hours are what let us hold a fixed price after the survey instead of adding day rates at the end. A property whose heat loss falls outside that band needs a different specification and a different figure, and only the survey shows which side yours falls on.
What Drives the Price: Property, Radiators, Cylinder and Electrics
Five things move the number, and each one shows up as its own line once the house has been measured.
Property size and heat loss
Every line on the quote is sized off this single figure. A draughty four-bedroom farmhouse on the edge of the Blackdown Hills asks for more output than a tight 1980s bungalow, and that gap shows up three times over: unit, cylinder and radiator schedule.
Sets every other lineRadiators
A heat pump sends cooler water to the radiators than an oil boiler did, and a panel fed cooler water gives out less heat than its catalogue rating. The survey checks each room at the design temperature. Guess high and you buy panels nobody needed; guess low and you find out in February.
The line that swings furthestCylinder size and siting
Four bedrooms and two bathrooms call for more stored hot water than two bedrooms and one. In older Devon properties the airing cupboard is often the only sensible home for the cylinder, and its position decides how far the pipework travels, so we measure that space at the assessment.
Bedrooms, bathrooms, cupboardElectrics and pipe runs
The heat pump needs a dedicated circuit and some consumer unit work on most installations so it runs safely, and a fixed quote states that cost before work starts. The further the outdoor unit sits from the cylinder, the more pipe, insulation and labour it takes to join them, so settle its position early.
A stated cost, up frontA real design, or a template with a price attached
James works as a freelance MCS assessor for NAPIT, so part of his week goes on inspecting what other companies have installed. The fault he keeps meeting is an outdoor unit picked off a generic sizing chart instead of calculated. An oversized machine costs more to buy, cycles on and off instead of running steadily, and wears itself out faster. Sizing correctly is one of the few decisions that lowers the price and improves the result at once.
Never printed on a quotationHow the Boiler Upgrade Scheme Cuts the Net Cost
The Boiler Upgrade Scheme turns the gross figure into something most households can plan around. Off-gas-grid homes replacing an oil or LPG boiler can qualify for £9,000, and that higher rate runs to 31 March 2027. Other eligible homes, including those on mains gas or direct electric heating, can qualify for £7,500. The grant is for owner-occupiers in England and Wales.
Worked on the typical £15,000 gross figure. Your own price comes from the heat loss survey.
How the grant reaches your invoice
James applies for you
Eco Pro is an MCS-certified installation company, so James makes the grant application on your behalf.
Taken off your quote
The full grant comes off the quote before you pay anything, so it never passes through your account.
Nothing to reclaim
You never wait for money to come back, and the 0% VAT on qualifying work needs no application of its own.
Eligibility turns on the property and your circumstances, so not every Devon home qualifies, and James checks yours at the free home assessment before anything is promised. The scheme carries on past 2027, so there is no cliff edge to panic about, but the higher rate for off-grid oil and LPG properties stops on 31 March 2027, which is the date to time an application against. Our guide to the £9,000 rate for off-grid oil and LPG homes sets out the eligibility rules and the cut-off in full.
The £250 Heat Loss Survey, and Why It Comes Off the Bill
Two visits sit between an enquiry and a fixed price, and the difference between them matters. The second one only happens if you want to go further.
Free home assessment
- Who comes James, who walks the property and asks what heats it now
- You get A straight answer on suitability and a fixed estimate on the spot
- Grant Your grant eligibility, checked at the same visit
- Cost No charge for the visit, and nothing to sign
Heat loss survey
- The work What the building loses, calculated room by room
- It sets Unit and cylinder size, flow temperatures and the radiator schedule
- Go ahead The £250 is deducted in full from the installation
- Stop here The survey is invoiced, because the design time has been spent
What the £250 buys
The survey produces the document your installation is built from, to the same standard James applies when auditing somebody else’s job.
What It Costs to Run, Without the Sales Arithmetic
Why this guide gives no savings figure
Any savings number produced without seeing your house would be fiction. What a heat pump does to your bills turns on the fabric of the building, how you run the heating, and above all which electricity tariff you sign up to. Set against cheap oil on a standard rate, the margin is thin.
The dependable gains sit elsewhere, and they are worth more than they sound. Heating oil is bought in lump sums, at whatever the market happens to charge in the week your tank runs low. Roughly 41,000 households across Devon buy their winter that way.
Tariffs written for heat pump households price those units lower again.
What stops once the oil tank goes
- Watching a float gauge slide down through December
- Booking a delivery slot
- Ringing round three suppliers to compare pence per litre
- Running the tank dry on the coldest weekend of the year
None of that replaces a figure worked out on your own house, which is why the survey produces a design and a fixed price rather than a savings estimate. Our guide to converting from oil to a heat pump covers how that works in practice.
Frequently Asked Questions
About £15,000 gross for a typical Devon property. Once the grant is deducted, most homeowners settle close to £7,500, and £6,000 where an off-grid oil or LPG home qualifies for the £9,000 rate, which runs to 31 March 2027. Your exact figure comes from the heat loss survey.
Book my free home assessmentYes. A Devon property that heats with oil or LPG and sits off the gas grid can qualify for £9,000 under the Boiler Upgrade Scheme, with that rate running to 31 March 2027. Other eligible properties can qualify for £7,500.
Book my free home assessmentNo. VAT on qualifying air source heat pump work in Devon sits at 0% until 31 March 2027.
Book my free home assessmentNo. The £250 is deducted in full when you proceed with the installation, and invoiced only if you decide not to go ahead, because the design work on your Devon property has already been done.
Book my free home assessmentThat depends on your Devon property, your usage and the electricity tariff you move to. The gains you can count on are predictable monthly bills and the end of oil deliveries, and any set figure off your bill depends on that tariff.
Book my free home assessmentA correctly sized heat pump and cylinder, the pipework and any radiator changes the survey identifies, the electrical work to run it safely, and commissioning. A cheaper Devon quote often looks cheaper because it leaves some of that out.
Book my free home assessmentGet an Honest Number for Your Own Home
Every property prices differently, and the only way to find where yours lands is to have somebody measure it rather than average it against a national figure. One free home assessment tells you whether the property suits a heat pump, what it would cost, and whether the grant applies.
Book my free home assessmentPrefer to talk it through first? Ring 01395 202030. James answers, and he is the person who will price the job.
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