Mitsubishi Electric UK Reviews 

We have been on 3 Diamond cover for 10 years now. Last year after the annual service we were informed that Mitsubishi now recommend we add an additional curculation pump, which would cost over £400. We agreed to pay this and the pump was duly installed. The pump is very noisy. The installation engineer said it would become quieter over the next week or so. It is still noisy, so much that, it is making part of our house uncomfortable. I have phoned multiple times over the past 8 months only to be told it is with the schedulers. Soon Mitsubishi will be requesting next years subscription fee for 3 Diamond service. I am in a quandary of what to do? No one at the Home Help number seems to do anything.

Update 24th January 2026
I have submitted all requeeted information to Mitsubishi and received apologies and a request for video with audio of the offending pump which I have gladly supplied. I have continued to enquire about progress in the matter only to receive the same response that it has been sent to the engineering team. Meanwhile we have this constant whine from the pump.
I believe they are not willing to sort this out or there AI led processes do not find a solution and my issue is left to continue. I entered into the 3 Diamond Support contract in good faith and have accepted every recommendation and charge they have made believing I was keeping my installation at peak condition. All I have received from Mitsubishi is apologies and the explanation the the engineering department are dealing with it.

Chris the engineer was very friendly. Let me know when he would arrive. Sorted out a leak and gave some advice on using our heating pump.

He was polite and efficient and did a thorough service check.

Subscribed to most expensive three diamonds plan thinking that they will provide better support but nothing is happening for a week already. Contacted them several times and all I hear is we'll get back to you when we'll have understanding when engineer is available. Complete waste of money and time. Dont pay for their support but find someone else instead

A Defective Heat Pump and Weeks of No Help – Extremely Disappointed
I have had a Mitsubishi Ecodan R290 10 kW heat pump since early September. The unit does not come close to meeting Mitsubishi’s published performance specifications.
Actual performance vs Mitsubishi specification:
• COP at 35°C flow, 7°C external: 1.4 (spec 5.1)
• COP at 35°C flow, 2°C external: 1.2 (spec 3.24)
• Noise level at 1 m: 68 dB (spec 47 dB)
My energy bills have doubled and my home is cold. It has had a real impact on our comfort and our life.
What happened when I asked Mitsubishi for help?
Despite reporting the issue on 22 October, Mitsubishi repeatedly delayed, passed responsibility around, and failed to take ownership. Their communication has been slow, contradictory and at times obstructive:
• Technical support acknowledged a site visit was needed 10 November, yet Mitsubishi failed to schedule one, then required a “warranty claim number” that their own staff failed to issue.
• I repeatedly had to chase, re-explain the issue, and even agreed to pay for the visit upfront just to get progress.
• Forms were “lost”.
• After weeks, the request was marked “urgent”, but still no visit date.
• When the unit finally failed with an error code (P8), Mitsubishi still offered no practical assistance or timeframe.
I also submitted a formal complaint referencing their own ISO9001 obligations. No response.
Summary
• The heat pump supplied is defective and far outside its published specification.
• Mitsubishi’s after-sales support has been unresponsive, disorganised and extremely slow.
• We are left with a cold home and extremely high electricity bills.
I expected far better from a company of Mitsubishi’s reputation. Based on my experience—and seeing over 140 other one-star reviews with similar themes—I cannot recommend Mitsubishi Electric UK.

We expected far better from a company with Mitsubishi’s reputation.

Our Ecodan Air Source Heat Pump failed under warranty, and as of today, 19 November, we’ve been without heating and hot water for 28 days.

We’ve chased repeatedly and requested a call from a senior manager — yet no one has contacted us.
We’ve now been given a repair date, but based on previous failed appointments, we’re not confident they will attend.

For a brand of Mitsubishi’s size, leaving a household without essential heating and hot water for nearly a month is totally unacceptable.

Communication has been poor, inconsistent and insulting - We were advised to use the immersion heater, despite Mitsubishi already having a report saying it doesn’t work.

We hope someone finally takes responsibility and that tomorrow doesn’t become another missed appointment.

We unfortunately bought our home in 2020 with a Mitsubishi heating system already installed, and it has been nothing but problems from day one. If I could give zero stars, I would. This has easily been the worst service experience I’ve ever had with any company.

Every single year without fail, we have had at least one major breakdown where we’ve had to contact Mitsubishi. And every year, their customer support manages to be just as slow and unhelpful as the last time.

Last December, the system failed completely and we were left with no heating and no hot water for the entire month. In the middle of winter. Mitsubishi eventually admitted we needed an entirely new outside fan unit installed — which in itself took far too long. In the meantime, we were forced to use expensive electric heaters and had to constantly boost the hot water just to shower, which sent our electricity bills through the roof. None of that was reimbursed or even acknowledged by Mitsubishi.

This year, once again, the system has failed. We repeatedly get an L9 error code every time we attempt to use the heating. Mitsubishi sent an engineer out last Monday — and unbelievably, he made the situation worse. He clearly had no idea how the system worked. He spent almost the entire appointment on the phone to Mitsubishi asking what to do, and after he left, the heating stopped working altogether without producing the L9 error every time. So we are now worse off after their “service” than before.

Considering we pay £400 per year for their Diamond Cover, the service we receive is frankly shocking. Their own policy claims to offer priority support and reliable cover (the document is online for anyone to read), but in reality, it’s nothing but broken promises. We are constantly forced to chase them, the wait times are ridiculous, and the level of support we get is the total opposite of what they advertise.

Their communication is slow, vague and unhelpful. They leave you waiting for updates, they repeatedly fail to resolve guaranteed faults, and they’ll happily take your annual premium without delivering the service they promise. The whole experience has been unbelievably stressful and completely unacceptable.

We are now heading into cold weather again and, thanks to Mitsubishi, we currently have no working heating system, despite having paid hundreds of pounds a year for cover that’s supposed to prevent exactly this situation.

On top of all this, we’re now in a position where we have to buy Mitsubishi’s Diamond Cover every year because the system is so unreliable that we’d be completely screwed without it. It’s not something we choose — it’s something we’re forced into because the system breaks so often and the repairs required are so expensive that we wouldn’t be able to afford them. And the worst part? Even with Diamond Cover, we’re left chasing them constantly, sitting on long hold times, and dealing with broken promises. For £400 a year, you’d expect priority service, competence, or at the very least some urgency — but we get none of that. It honestly feels like we’re paying a premium just to be ignored slightly slower.

I would strongly advise anyone considering a Mitsubishi heating system — or their Diamond Cover — to think very carefully. Our experience since 2020 has been nothing but ongoing faults, delays, incompetence, and extra costs. Truly awful service.

New house, new Ecodan Heat pump system, still no room heating for 6 months. Two service Engineer visits, Ecodan have taken £2069 from me for the 2 visits and there flag ship service package, “3 Diamond cover”which has 24 response time. The response has been 9 days to book an Engineer who will arrive at the property 24 days after reporting the fault. To add insult to injury they invoiced me for £309 to pay for the 3rd Engineers visit which turned out to be mistake in their favour.

There are 9 new houses on the estate and all have Ecodan systems, all of which have had similar problems and new heat pumps in 2 cases. For a company renowned for excellence within Engineering circles Mitsubishi Electric have really dropped the ball with this product and their UK operation, I wonder if the CEO Kei Uruma nows this?

Ecodan ref RZ61010, 350011815 (CM)

Brand new house. Ecodan not working. Our installer tried 4 times to fix it, decided Mitsibushi would have to look at it. Waited 4 days for a response. Finally told 2 week wait. Overpriced crap. Customer service zero.
They may be good at yearly servicing [money].
Try & get a repair & they don't want to know.
Buyer Beware!!

From the time the booking for a repair/service it took 2 days shy of five weeks for the engineer to arrive. Thankfully we had hot water and the weather late October and November has been mild so not having heating was not too bad. So if I were scoring the booking to completion it would be 2 stars…but I’ve given 5 stars for the job Joe the engineer did during the visit today. Joe was extremely courteous and answered all my questions in a plausible and friendly way. He had to replace the entire heating main circuit board as this was the reason the heating was not working. All now up and running…looking forward to waking up to a warm house tomorrow..thank you Joe!!

Contacted ME regarding my very old Ecodan - turns it's not really fixable. Ok that's fine.

My issue is that it was a week of rescheduling to get the engineer here and in doing so I lost £155 in client hours as no contact was made for the first two days then rescheduled on the 3rd and he didn't turn up at the expected time on the actual day. Their customer relations teams said this was not acceptable and they'd dropped the ball and would look at refunding me as the cost of getting them out was eye watering. This was ok with me and I felt heard and understood. 15 days later still no 'goodwill gesture' as agreed with the second customer service agent. It is then escalated to another person who tells me it's another 15 days. I'm still waiting and despite emailing them back they're not answering.

I run a very small business and the money I lost has to come from somewhere. I cannot understand WHY after 25 days they can't issue a small (let's face it, it is small for them) refund AND no one will respond to me.

I'm really disappointed I chose to use this company.

24/11/25. It’s now past the 15 extra days outline and despite numerous emails AND this review no one is contacting me back and the payment has not yet eventuated. Based on my experience and lack of any form of follow up I’d highly advise people to be VERY cautious of this company.

Steve was very understanding and did the service with minimal noise, extremely clean and such a nice chap. He also helped with a few questions and niggles I had which he sorted. Brilliant.

The engineer (Steve) who visited my property to service my air source system deserves a 5 star review, he was extremely professional, helpful and polite. Unfortunately he was let down by the team who book the appointments for the service engineers. I made several phone calls and wrote a number of emails (including a complaint) before an appointment finally came through. Not good, how difficult can it be to work out a date and book it in the diary. It’s hardly rocket science!

Chris the engineer called me on route and arrived promptly for my morning appointment. He was very friendly and respectful of our property. He fixed our problem swiftly and double checked many other elements just to ensure our ASHP system was all good. Very good communication, Chris answered all my questions with great system knowledge and he was very helpful.

Luke was super helpful with our service and fix for our leak. Great communication.

The 5 stars are for Steve who did our annual service. Covered every aspect of the heat pump and heating system. He was really knowledgeable and helpful and fixed a few issues while he was here. Great engineer.

I'm still waiting to hear from an Engineer to service my ecodan heat pump. i contacted them 2 weeks ago and since several times. I was told that an Engineer would contact me but still nothing.
If the government want us to all have them then we need the service and maintenance to cover.
I did go with another company last year but useless so thought i would go direct to Mitsubishi thinking I would have a better service but NO!!!
I received a government grant for the pump and will be making a formal complaint about the difficulty with Mitsubishi. The warranty is not valid unless it is serviced annually .

Paul attended our property to carry out a service of our heat pump. He was courteous, professional and very helpful, answering a couple of questions we had. He left everything clean & tidy, very happy.

5 stars to Robert for not only resetting our ASHP controls to improve efficiency but for taking the time to carefully explain to us oldies what he was doing and why. What he has done just makes so much more sense compared to how it was originally set up by the installer. Fantastic!

Luke was superb! Explained everything in detail and really polite and friendly. Recommend!

Luke was exceptionally good - professional, knowledgeable, thorough, careful, polite, thoughtful, informative and cheerful. He carried out the inspection and service efficiently and explained the complexities of the system clearly and helpfully and answered questions patiently and straightforwardly. He discovered a couple of aspects of our system which needed attention and made good suggestions on how to go about getting these sorted in the best way with a guide to the timeline required. We feel fortunate that he was assigned to our Mitsubishi Air Pump service today.