How to Choose a Heat-Pump Installer in Europe (the Grants Hinge on It)

A heat pump is only as good as the person who installs it. The same unit, on the same house, can deliver the running-cost cut on the brochure or a noisy box that quietly drains your electricity - and the difference is almost entirely the install. In Europe the stakes are doubled, because the grants that cover a large part of the cost are usually conditional on using a certified installer. Choose the wrong fitter and you can lose both the performance and the subsidy.

This guide covers how to choose an installer who protects both. For the grant landscape and the retrofit sequence around the unit itself, see our guide to heat pumps and energy retrofits in Europe.

The grant is tied to the installer, not just the kit

Across Europe, heat-pump subsidies flow through accredited installers. The scheme names differ - MCS in the UK, RGE in France, certified-installer requirements in Germany, Enova's approved-contractor route in Norway - but the pattern is the same: use a fitter without the right accreditation and the grant is simply not paid, however good the equipment. Before anything else, confirm the installer holds the exact certification your national or regional scheme requires, and that it is current. This is the first filter, and it removes most of the field.

Sizing is the whole game

The single most common install failure is a guessed size. A heat pump that is too big short-cycles, wears out and runs inefficiently; too small and it cannot hold the house in a cold snap. A competent installer does a room-by-room heat-loss calculation - the EN 12831 method - before quoting, not a rule of thumb based on floor area or the old boiler's output. If an installer quotes a model without measuring your heat loss, that quote is a guess, and you should treat it as one.

Insulation and flow temperature come first

A heat pump works best when the house needs little heat and the water runs cool. A good installer looks at the fabric before the unit - insulation, glazing, draughts - because a heat pump on a leaky house delivers exactly the disappointing bills that give the technology its bad name. They will also design for a low flow temperature, often with larger radiators or underfloor pipes, because efficiency falls sharply as flow temperature rises. An installer who talks only about the box, and never about the house or the flow temperature, is selling you a unit, not a system.

What else to verify

• F-gas certification: handling refrigerant is regulated across the EU under the F-gas rules, and the installer or their engineer must be certified to do it.
• Manufacturer accreditation for the specific brand - it is often what backs the longer warranty.
• References to installs at least two heating seasons old, and ask those owners about winter performance and running cost, not just the fitting day.
• Noise and placement: outdoor units have noise limits and, in some countries or historic zones, need a permit or neighbour consent for where they sit.
• A commissioning handover - the installer should set and record flow temperatures, refrigerant charge and controls, and give you the data.

The red flags, in one place

• A model quoted without a room-by-room heat-loss calculation.
• No certification for your grant scheme, or vagueness about which they hold.
• No F-gas certification for handling the refrigerant.
• Talks only about the unit, never the insulation or the flow temperature.
• No references older than a single heating season.
• Pushes you to sign before the grant paperwork and certification are confirmed.