Diamond Green Energy Ltd Reviews 

2,701
TrustScore 5 out of 5

4.9

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Review summary

Created with AI, based on recent reviews

Looking at 337 reviews, reviewers overwhelmingly had a great experience with this company. Customers frequently praise the professional and knowledgeable engineers who always arrive promptly, respect people's homes, and complete solar and boiler installations smoothly from start to finish. Consumer feedback focuses on the exceptionally helpful support team, emphasizing that staff members are polite, responsive, and always ready to explain every technical detail clearly. Some reviewers were not happy with specific aspects of the service, mentioning poor aftercare support or unexpected technical problems with heating systems following maintenance visits. People also mentioned encountering frustrating situations where responses to post-service complications fell short of expectations and left them seeking alternatives.

What people talk about most

Service

Reviewers mention positive feedback about service, noting that engineers are polite, professional, and carry... See more

Staff

Clients share positive opinions on staff, highlighting their professionalism, efficiency, and friendliness... See more

Customer service

People report positive experiences with customer service, noting that communication is consistently excellent... See more

User experience

Customers had positive experiences with user experience, reporting helpful and professional service from... See more

Product

Users describe positive interactions with product, expressing great satisfaction with the overall quality and... See more

Reviews shaping this summary

Rated 5 out of 5 stars

Charlotte makes the booking process very easy. I love that you get a message the night before giving a 4 hour slot for the engineer visit and then on the day of the visit you get a message when the... See more

Company replied

Rated 5 out of 5 stars

We had our boiler moved as part of a loft conversion and Steve and Tom were both brilliant. They genuinely went above and beyond, were really professional throughout, and made the whole process easy a... See more

Company replied

Rated 5 out of 5 stars

Good service. Company kept in touch about timing. Clean tidy engineer who not only serviced our boiler bought from Diamond but service our gas fire thoroughly too. Excellent service, 9 years we have b... See more

Company replied

Rated 5 out of 5 stars

Diamond Green Energy installed 18 solar panels, inverter and battery storage. The work was more demanding on an old house. All members of the team were good to have onsite. They were quick to resolve... See more


Company details

  1. #10 of 45 best companies in Gas installation service
  2. #4 of 23 best companies in Air Conditioning Contractor
  3. #8 of 60 best companies in Gas engineer
  4. #13 of 74 best companies in Central Heating Service
  5. #13 of 119 best companies in Heating service
  6. #2 of 52 best companies in Solar Energy Company

Written by the company

We are a family run renewable energy company based in Fareham, Hampshire. Our approach has always been to provide an honest, trusted and reliable service to our clients and this has supported our business growth over the last 16 years. At Diamond Green Energy we ensure that all of our engineers are kept up to date with all the latest training offered by manufacturers, ensuring that our customers receive nothing but the best service. As a MCS registered company, we also offer you peace of mind. We strive to continually keep up to date with industry changes and new and innovative products that are entering the market so that we can offer our clients the best possible energy saving solutions. If you would like to discuss renewable energy solutions for your property or business


Contact info

4.9

Excellent

TrustScore 5 out of 5

3k reviews

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Replied to 100% of negative reviews

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4.9

All reviews

(2,701)

300 reviews in the last 12 months

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polite

Rated 5 out of 5 stars

Excellent service in an emergency

After my tenant's boiler failed, (and the management company took too long to arrange firstly the initial repair, then estimates for a new boiler), I found this company via the Gas Safe register. They carried out a video survey with me and the new boiler was fitted and running two days later. All through this, their customer service was helpful, polite and responsive, despite being very busy.

22 January 2026
Unprompted review
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Reply from Diamond Green Energy Ltd

Thank you for taking the time to review us.

Rated 5 out of 5 stars

Boiler service

Had Robert nugent attend for annual boiler service. As usual he was very polite and asked if I had any problems. And done the service promptly and efficiently. As always a 1st class service from a 1st class company. Thank you .

16 January 2026
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Reply from Diamond Green Energy Ltd

Thank you for taking the time to review us.

Rated 5 out of 5 stars

New Gas Boiler Installation by Diamond Green Energy

Gas boiler installation was carried out by Steve who was spot on the appointment time, had a quick look at site to make sure everything was as the tender. Steve kept my wife and I informed throughout the installation, worked very hard to make sure the new boiler was up and running by mid afternoon which it was; a nice and warm house after two weeks without heating. Steve was very polite, professional and efficient plus he left the area near the boiler spotlessly clean. Thank you.

15 December 2025
Unprompted review
Rated 5 out of 5 stars

Professional company

Generally a good experience Jake always returns calls if I have a general home owner question, still getting used to a ASHP system over a gas boiler, but happy with Diamond greens energy proses, plus the work force were competent and especially polite which went a long way. Yes I would recommend them

16 September 2025
Unprompted review
Rated 5 out of 5 stars

They did a great job

They did a great job, very polite, clean tidy and worked very hard being meticulous to detail. Came recommended to me and I would recommend them to anyone. If you want a good job doing this is the firm.

4 December 2025
Rated 5 out of 5 stars

Had Solar installed by Diamond Green…

Had Solar installed by Diamond Green Energy. Mathieu was very informative and helpful through the survey stage. Everyone who came to site were very hard working and extremely polite throughout. Even in the pouring rain! Would definitely recommend.

20 November 2025
Unprompted review
Rated 5 out of 5 stars

Excellent company highly recommended …

Engineer on time very polite respectful and professional carried out work no mess left
Easy booking once over coming AI instructions which has been newly installed and requires consideration for elderly users

19 November 2025
Rated 5 out of 5 stars

Boiler check

Easy to make an appointment, was given a time slot and received a text to let me know engineer was on his way. Very polite, worked without leaving any mess, explained and showed me with photos what had been done.

17 October 2025
Rated 5 out of 5 stars

Solar panel installation. First rate experience

I was so very impressed from start to finish with the installation of our solar panels. All questions (of which there were many and often technical) were quickly and accurately answered.

The end-to-end process of the team from surveyor, scaffolders to the final installation was streamlined.

The two engineers (Declan and Andy) were very polite, courteous and highly professional throughout. I couldn’t rate them higher. Attention to detail and setup of the hardware was clear for all to see. They both worked hard, consideration to the layout of the battery and inverter with no corners cut.

22 September 2025
Unprompted review
Rated 5 out of 5 stars

Professional & polite service as usual.

I was unable to have my Boiler Serviced on the usual annual date due to Cancer Treatment.
I explained this when my reminder was sent to me & they were kind enough to postpone it for several months & gave me a new date.
I phoned nearer my due date to check when the engineer would be attending as advised them I was still having Radiotherapy in the morning. Thankfully the engineer was coming in the afternoon.
I had a message stating the name of the engineer & that he was on his way & arrived promptly 15 minutes later. He introduced himself + was polite on arrival.
The engineer also helped me download the app for my thermostat to my new phone & stated if I still had issues with the app to let him know & he would pop round to sort it for me.
As always I was very impressed & pleased with the whole service.
Thank you Diamond Green Energy.

26 September 2025
Diamond Green Energy Ltd logo

Reply from Diamond Green Energy Ltd

Thank you so much for your feedback. We are truly sorry to hear about your health challenges and hope your treatment is going well. It really does mean a great deal to us that, even during such a difficult time, you have taken the time to share your experience. Your continued support means the world to us. We all wish you all the best in your recovery.

Rated 5 out of 5 stars

Efficient and competent service.

Both Drew and his colleague Max were polite and friendly. They completed the boiler and heating system service efficiently and on time.

19 September 2025
Diamond Green Energy Ltd logo

Reply from Diamond Green Energy Ltd

Thank you for taking the time to review us. It really is appreciated.

Rated 5 out of 5 stars

Boiler service

Very happy with service very polite young man and no mess when doing service.

29 August 2025
Diamond Green Energy Ltd logo

Reply from Diamond Green Energy Ltd

Thank you for taking the time to review us, your business is appreciated.

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