Commercial heat pump installation FAQs

An air-source retrofit is typically 4-12 weeks on site once design and any DNO supply work are agreed, and the live boiler cutover is usually a matter of hours. Ground-source and water-source take longer because of drilling, ground works and permits, often several months. Industrial, process and heat-network schemes run to 12 months or more including design, planning and grid works. The DNO supply upgrade, where one is needed, is frequently the longest-lead item, which is why we start it at feasibility rather than install week.

No. We plan the changeover around your operating calendar, typically spring or autumn, and for a hybrid or phased design the existing boiler stays live as backup right through commissioning, so you're never without heat. Air-source plant is largely pre-assembled, so the live cutover is a matter of hours. Every tie-in is method-statemented and agreed with you before we mobilise.

Often not, and we survey your emitters before we design anything, so you know for certain. Many commercial systems run a heat pump at 50-55 C with selective emitter upgrades rather than a full strip-out. Where high flow temperatures are genuinely needed, a high-temperature heat pump (70 C+) or a hybrid design with a peaking boiler avoids re-emittering the whole building while still cutting carbon 70-90%.

From a heat-loss survey and at least twelve months of gas or oil consumption, never from floor area. Sizing sets the peak heat load and the flow temperature the emitters allow, because a lower flow temperature lifts the SCOP. Typical commercial air-source systems land between 40 and 500 kW thermal; ground and water-source 50 kW-1 MW+; industrial and heat-network schemes larger again. We specify to BS EN 14825 so quoted performance is comparable across suppliers.

We check that at survey, before anything is ordered. Large heat pumps add meaningful electrical load, so we confirm your available incoming supply capacity, and where a DNO supply upgrade is needed we start it at feasibility because it's often the longest-lead item. On constrained sites we look at phasing, hybrid designs or demand management to stay within capacity.

Many commercial air-source installs fall under permitted development, but they're subject to siting and noise limits, so a BS 4142 acoustic assessment is commonly required to show the external plant won't disturb neighbours, and we produce it before the plant is ordered. Listed buildings and conservation areas need consent, and ground-source or water-source schemes may need planning and an Environment Agency permit. We confirm all of this at feasibility.

Air-source is the fastest and least disruptive: no ground works, plant craned to a compound, cutover in hours, but siting and acoustic are the delivery risk. Ground-source is drilling-led, a thermal response test and boreholes precede final design and the programme is longer, but efficiency is the highest and most stable. Water-source is source-consent led, needing an intake and an EA permit, and suits waterside sites. We model and programme all applicable options from your data before recommending one.

A hybrid (bivalent) install pairs a heat pump with a peaking boiler. The heat pump covers 70-90% of annual heat, the vast majority of operating hours, and the boiler tops up only on the coldest days. It needs a smaller, cheaper heat pump, suits buildings with high-temperature emitters, keeps the existing boiler as backup through commissioning, and de-risks the worst-case cold spell. For many commercial retrofits it's the most cost-effective and lowest-risk decarbonisation route.

SCOP (Seasonal Coefficient of Performance) is the average heat output divided by electricity input across a whole heating season, measured to BS EN 14825. An SCOP of 3.5 means 3.5 units of heat per unit of electricity. We design to it, the biggest lever is a low flow temperature, and we commission and witness the system against the design so the delivered performance is proven, not promised. Because we quote to BS EN 14825 and 14511, our figures are directly comparable to any compliant supplier.

It depends on technology and scale. Air-source typically runs £60,000-£600,000; ground-source £150,000-£2m+ because of the ground works; hybrid boiler-replacement £70,000-£500,000; water-source and heat-network schemes higher again. Cost is driven by the peak heat load, the emitter upgrades required, external-plant siting, and any electrical supply upgrade. We model the full installed cost from the heat-loss survey before you commit, no blind quotes.

No. The Boiler Upgrade Scheme is domestic-only and does not cover commercial or non-domestic buildings. Commercial buyers have different, often larger, routes: the Public Sector Decarbonisation Scheme (public bodies), the Industrial Energy Transformation Fund (eligible industrial sites), the Green Heat Network Fund (multi-building schemes), and Annual Investment Allowance capital tax relief for any business. We map which of these you qualify for and align the application with the delivery programme.

It depends on the design. In a heat-pump-only project the boiler is decommissioned and removed once the new plant is commissioned and proven. In a hybrid design the boiler is retained as the peaking and backup source, and we re-certify its flue, gas train and interlocks as part of handover. We can keep the old boiler live through commissioning either way, so the building is never without heat during the changeover.

Yes, particularly ground-source and water-source, which deliver low-cost passive or active cooling in summer by reversing the flow, and air-to-air systems which heat and cool by design. That's valuable for offices, care homes, hotels and spaces with IT or process heat. A reversible install means one plant set covers both seasonal duties, which we factor into the plant-room and controls design.

Modern units use lower-GWP refrigerants such as R32 (A2L) and increasingly natural refrigerants like R290 (propane), CO2 and ammonia for high-temperature duties, driven by the F-Gas phase-down. Natural and flammable-refrigerant plant carries DSEAR/ATEX siting requirements, which change the plant-room layout and ventilation, so we design for them from the start. All refrigerant work is carried out by F-Gas certified engineers.

Drilling needs a compound, rig access and space for arisings, and it's the noisiest, most space-hungry phase, so we plan it into the site logistics up front, often out of term time for schools or around a hotel's quiet season. A thermal response test and ground investigation come first to confirm the loop design. Once the array is in and grouted, the field is invisible and can last decades; it's the drilling weeks that need managing, not the finished system.

A documented, witnessed commissioning: the SCOP and control settings verified against design, the electrical and F-Gas certification, the acoustic sign-off, the as-installed drawings and O&M manual, and a planned maintenance regime. Where a grant funded the work we provide the evidence the funder needs. It's the records a commercial insurer, auditor and net-zero report expect, not just a set of keys.

Yes, and the install is what makes them reliable. Air-source output dips as it gets colder, which is why we size for the peak and, where needed, pair a peaking source for the rare extreme days. Ground-source and water-source draw from a stable source and barely move with air temperature, so performance holds in the coldest snaps. The design and commissioning prove the coldest-day behaviour rather than leaving it to chance.

Annual or six-monthly servicing covers the refrigerant circuit, electrical checks, controls and a performance review against design, and remote monitoring flags underperformance early. With routine maintenance, commercial heat pumps have a service life around 20 years (15-20 for air-source; the borehole or water array of a ground/water-source system can last decades). We hand over a planned O&M regime and can carry it out under a service agreement.