Mitsubishi Ecodan heat pumps

What Ecodan is

Ecodan is Mitsubishi Electric’s range of air-to-water heat pumps. The outdoor unit draws heat from the outside air and transfers it into water, which runs through your radiators or underfloor heating and heats a hot water cylinder. It’s designed to replace a boiler as the main heating for a home.

It’s a different product from Mitsubishi Electric’s air conditioning, which heats or cools the air in individual rooms. Our guide to heat pumps and air conditioning explains the difference.

The Ecodan R290 range

Mitsubishi Electric’s current domestic line-up is the Ecodan R290 range. Mitsubishi Electric says:

• It comes in 5, 6, 8.5, 10 and 12 kW sizes.
• It uses R290, a natural refrigerant with a GWP of 0.02.
• It can deliver flow temperatures up to 75°C and is designed to keep operating down to -25°C outside.
• It works with Ecodan cylinders and with existing microbore pipework.
• It is controlled by the Flow Temperature Controller 7 (FTC7), with MELCloud for phone control.

Ecodan units are monobloc: the refrigerant circuit stays in the outdoor unit and only water pipes enter the house, so there’s no refrigerant pipework indoors. The cylinder and controls sit inside, usually where a hot water tank or airing cupboard is now.

Designing the system

The right size depends on how much heat your home loses on a cold day, not on the size of your old boiler. At the survey we carry out a room-by-room heat loss calculation, check the radiators, look at where the outdoor unit and cylinder can go, and agree a design flow temperature. Lower flow temperatures run more efficiently. Although Ecodan R290 can reach 75°C, a well-designed system rarely needs to run that hot, and sometimes a few larger radiators make a real difference to running costs.

The £7,500 Boiler Upgrade Scheme grant

In England and Wales, the Boiler Upgrade Scheme gives £7,500 towards an air source (air-to-water) heat pump such as Ecodan. As an MCS certified installer we apply for the grant, and it comes off your bill. Conditions include one grant per property, no grant to replace an existing low-carbon system, and no hybrids. Until March 2027 there is an extra £1,500 for air source or ground source heat pumps in homes heated by oil or LPG with no mains gas.

Our air-to-water heat pump prices are £8,000–£16,000, with 0% VAT on homes, before the £7,500 grant. HMRC Notice 708/6 zero-rates heat pumps installed in homes until 31 March 2027, then 5%. This is general information, not tax advice. See also our article on 0% VAT on heat pumps.

Planning and noise

An air source heat pump on a house in England is often permitted development, as long as it meets the limits: an outdoor unit (with housing) of no more than 1.5 m³, compliance with MCS 020(a) including its noise check, and rules on where it can go. Mitsubishi Electric says the Ecodan R290 holds Quiet Mark accreditation. Listed buildings, conservation areas, flats and Article 4 areas need extra checks, which we cover at the survey.

Ecodan warranty

Warranty on an Ecodan comes from Mitsubishi Electric, and its Ecodan warranty page explains that the length of cover depends on the installer’s status with Mitsubishi Electric, ranging up to 7 years for its highest installer tier, under its published terms and conditions. Mitsubishi Electric recommends that homeowners complete its Ecodan Guarantee form.

We don’t claim a Mitsubishi Electric installer status. We explain exactly which manufacturer’s warranty applies to your system on your quote, help you register it and keep the annual service records it depends on.

Installing an Ecodan: what to expect

Once the design is agreed and the grant application is in, most of the work happens in a few days. The outdoor unit goes on a solid base or brackets where it has clear airflow and meets the planning limits. Inside, the Ecodan cylinder usually replaces an existing hot water tank, and the FTC7 controller is fitted where you can reach it. Radiators that need upsizing are swapped, and the old boiler is disconnected. We then fill and balance the system, commission it, and walk you through the controls and the MELCloud app before we leave. You get the MCS certificate and the commissioning paperwork, which the warranty and the grant both rely on.

Living with an Ecodan

A heat pump works best running steadily at a lower temperature, rather than blasting on and off like a boiler. Most people find it works well left on a schedule, with small changes rather than big ones. An annual service checks the system pressure, filters, controls, cylinder and outdoor unit, and keeps the service history Mitsubishi Electric’s warranty asks for. If something isn’t right, MELCloud can help show what the system has been doing, which makes diagnosis quicker.

Strengths and things to consider

Strengths: a long-established heat pump range in the UK; a natural refrigerant; high flow temperatures for older homes; and a monobloc design with no indoor refrigerant work.

Things to consider: you need room for a cylinder; R290 units have siting rules because the refrigerant is flammable; and the warranty you get depends on the installer’s status, so ask every installer which terms apply. Compare it with the Daikin Altherma.