“Our combi-boiler failed, I contacted Carl having found his details on which? trusted traders. He visited the same day to identify the issue. Unfortunately the failure was terminal for our 16 year old boiler. He researched replacements, giving us a few alternatives. Once we decided on the replacement, he purchased & arranged to replace the boiler, all done within a few days. He kept us updated throughout, clearly outlined the potential cost, which was the final cost & cleaned up following the installation. I would definitely recommend Carl & wouldn’t hesitate in using him again if needed”
Public evidence profile
Gas Proco (London) Ltd
Credentials & registries
Which? Trusted Trader
Companies House
Active incorporated business
Trust Score
59out of 100
- 13 reviews in the last 12 months
- 1 credential shown
How this score is worked out
Review volume59
Independent sources2 independent public sources
Credentials1 credential shown
How this score is made up
What customers say37.1 of 60
Independent checks11.7 of 30
Track record10 of 10
See the independent checks
- Licences and credentials0.6 of 8.3
- Ways to reach them7 of 8.3
- Reviewed on more than one site0 of 6.2
- Registered company details4.1 of 4.1
- Photos of their work0 of 2.1
- Industry recognition0 of 1
Missing evidence lowers the score because we can't check it. It doesn't mean it doesn't exist. Claiming a profile never changes the score. Evidence context, not a guarantee of workmanship.
Trust at a glance
2 checksWhat we can verify about Gas Proco (London) Ltd
Each card sums up one thing we can check from public sources. Open it for the full detail and the named source. This is evidence context, not a guarantee.
Credentials & registriesWhich? Trusted TraderSee detail →Companies HouseActive incorporated businessSee detail →
See the full verification checklist for Gas Proco (London) Ltd →Reviews · public evidence
What customers say
These reviews are published independently on the named public source below, not testimonials this business chose to show. We bring them together and link each one back to where it appeared, so you can open the source and read it yourself.
No rating
Customers often mention
Where these reviews are published
- Which? Trusted Traders59 reviews
Highlights
“I called Carl as I had lost all water pressure in my flat and he helpfully came out that day to rectify the issue, which he did very efficiently, especially considering difficult access to the source of the problem. Carl is very friendly and helpfully advised on some simple maintenance items I could do myself based on wear and tear he could see developing in my bathroom. I feel relieved to have found someone I can trust and rely on - thank you!”
“Carl was brilliant. He diagnosed a pressure issue with our boiler very quickly, explained the problem, set out the cost to fix it, and completed the job very efficiently. It has been working perfectly ever since. Carl was very friendly and made himself available on the same day to fix the issue. He was professional and gave us some excellent advice on boiler maintenance going forwards. Would strongly recommend.”
Detailed reviews
These are the individual reviews we hold for Gas Proco (London) Ltd, including the highlights above. The 59 headline total is the review volume reported across public review sources.
Failed Combi-Boiler
Our combi-boiler failed, I contacted Carl having found his details on which? trusted traders. He visited the same day to identify the issue. Unfortunately the failure was terminal for our 16 year old boiler. He researched replacements, giving us a few alternatives. Once we decided on the replacement, he purchased & arranged to replace the boiler, all done within a few days. He kept us updated throughout, clearly outlined the potential cost, which was the final cost & cleaned up following the installation. I would definitely recommend Carl & wouldn’t hesitate in using him again if needed
Would highly recommend
I called Carl as I had lost all water pressure in my flat and he helpfully came out that day to rectify the issue, which he did very efficiently, especially considering difficult access to the source of the problem. Carl is very friendly and helpfully advised on some simple maintenance items I could do myself based on wear and tear he could see developing in my bathroom. I feel relieved to have found someone I can trust and rely on - thank you!
Brilliant service - strongly recommend
Carl was brilliant. He diagnosed a pressure issue with our boiler very quickly, explained the problem, set out the cost to fix it, and completed the job very efficiently. It has been working perfectly ever since. Carl was very friendly and made himself available on the same day to fix the issue. He was professional and gave us some excellent advice on boiler maintenance going forwards. Would strongly recommend.
Professional, prompt and polite
We called Carl on the middle of a cold Friday afternoon after discovering a hot water issue. He was polite and professional over the phone and was able to attend the next day, ie Saturday. (He also said he would let us know if he was able to finish his current job on time to attend on Friday evening, which was appreciated as it would have meant we got it fixed sooner, and at a cheaper weekday rate.) He gave us a 2-hr arrival window for Saturday and messaged 20 minutes into this slot, already there and having assessed it was likely only going to need the initial hour’s call out charge to resolve. This “live” update as I wasn’t there was super helpful - and he also took the time to explain what the issue was and what needed to be done in future. Carl’s weekend rate for central London was competitive. His excellent service level, communication and ease of arranging his visit also means it was good value for money. He will be the first person we call next time we need help. Thanks very much.
10/10. Highly recommend
Excellent service from start to finish. Carl was recommended to us by a neighbour and was helpful and communicative throughout the process. The timeframe from initial contact to having the work completed was very fast and he was happy to work around our schedule.
Read the other 15 detailed reviews on this pageShow fewer reviews
Great service - New Boiler
I have used Carl a few times now. Most recently he installed a new boiler for me. Always does a great job. Really helpful, trustworthy & wonderfully responsive. Would highly recommend him. I wouldn't use anyone else.
Trustworthy and responsive plumber
Change of shower including tile replacement in the surround. The work was quoted and carried out within amazing timescales and to a fantastic standard. Professional, good value and trustworthy. I was given two quotes dependent on the level of work needed - which wouldn’t be known until the work had started - they could have just charged me the upper end. Hard to come across a company like this these days. Carl was brilliant. I think it is worth noting that another well established company had quoted me nearly double!!
Great Service
Carl came to replace all my radiators and move pipes in a cupboard in order for a fridge freezer to be installed in that space. He is efficient, thorough and good value. Very polite and respectful too. More importantly he’s knowledgeable and knows what he’s doing! I highly recommend Carl and will be using him again to move a boiler.
Great service
100% recommend and will be using for future services. Fixed my leaky tap and conducted a boiler service. Was professional and polite. Good communication throughout.
Boiler service and leaky pipe
The first time I have used Carl and I was most impressed. He was punctual, polite, thoroughly professional. I was concerned about a leak under my kitchen sink which Carl dealt with straight away. I feared a big job, but fortunately, it just needed tightening up. That fixed it. Boiler service carried out efficiently as expected. Carl charged for the boiler service only, no charge for dealing with the leak. Very happy with the service provided. I will happily recommend Carl.
Excellent service
Carl serviced my boiler today. He did a fantastic job and was extremely thorough and efficient. A part needed replacing which he went to purchase and returned to fit immediately. Can highly recommend and am pleased to have found such a reliable and pleasant plumber. Will definitely be a repeat customer.
Excellent service, efficient and professional
Carl serviced my boiler and gas fire today, and also checked my central heating. He was professional and thorough, and all is in good order for the coming winter. Highly recommended!
Totally reliable
Great service every time. Punctual, thorough and a thoroughly nice guy! I have recommended Carl to most of my neighbours.
Great Engineer
Carl was extremely professional and was great to work with. I had no heating at all, so he installed a complete central heating system from scratch. I also had an old, leaky bathroom removed and completely replaced. Carl works very tidily and is very easy to talk to to get just the finish I was looking for. I now have heating for the winter and a fabulous bathroom that I can’t wait to show off and tell all my friends about.
Boiler replacement - great service
Similar to other reviews, Carl did a fantastic job replacing my boiler. He is refreshingly honest and really helpful. The job was completed in one day (including moving the boiler to a new wall), and the work is so obviously better than the previous boiler fitter. I wouldn’t hesitate to recommend his services.
Great work and very efficient
Carl turned up on time examined the work [leaking pipe in concrete floor] gave me a approximate price and started to work his magic. He worked efficiently and cleanly tidying up after he finished and to my surprise the price was less than I was expecting. Well done
Excellent job fixing boiler
I always prefer to use recommended tradespeople and Carl was recommended when I asked in a Facebook group about heating engineers available to work in Clapham, London. Carl was friendly and did a great job fixing my boiler, I thoroughly recommend him.
Outstanding Service – Highly Recommended!
I had a fantastic experience with Carl. The job was carried out professionally, efficiently, and with great attention to detail. Everything was left clean and tidy afterward, which I really appreciated. It’s clear they take pride in their work, and it shows in the quality of the result. Reliable, courteous, and skilled—exactly what you hope for in a tradesperson. I wouldn’t hesitate to use their services again or recommend them to others. Thank you for a job well done!
Great work and reliable
This is the second time we have used Carl's services. He knows his craft, is very reliable, amiable, and punctual/tidy. Would have no reservations recommending Carl to anyone - another great job !
Great service!
Carl is super responsive and helpful, and very reasonable prices! Thanks so much for the boiler service.
From customer reviews
What customers consistently say
Recurring themes from 26 customer reviews on Which? Trusted Traders.
Respectful and tidy in your home: “He worked efficiently and cleanly tidying up after he finished” · Which? Trusted Traders, 28 May 2025
“His excellent service level, communication and ease of arranging his visit” · Which? Trusted Traders, 11 Jan 2026
“His communication was excellent” · Which? Trusted Traders, 27 Mar 2025
“Carl had fantastic communication” · Which? Trusted Traders, 27 Feb 2025
Credentials and associations
1Credentials and memberships
These credentials and memberships are attributed to named public sources. Check the source before relying on them.
- Source checked
- 25 Jun 2026
Companies House registration
ActiveActive incorporated business
GAS PROCO (LONDON) LTD is linked to a Companies House entry. This shows the business registration, not evidence of workmanship or service quality.
Legal nameGAS PROCO (LONDON) LTD
Company number08886484
Incorporated
Registered activityPlumbing & heating installation
Run by1 director (longest-serving director appointed in 2014)
Previously traded asCAPITAL MAINTENANCE & INSTALLATION LTD (until 2025)
Official checkOn the public register
Why this helps you judge trust: this trader is linked to a registered company with named people who are legally accountable for it, on an official register anyone can check, a layer of accountability an unregistered trader doesn't offer. Around 12 years on the register also points to an established business rather than a brand-new one.
Sources
2 named public sourcesWhere this information comes from
Everything on this page is drawn from named public sources. Where a source provides a public link, you can open the original and dig deeper.
Review sources
Business and public registers
Check dates vary by source. Where we hold a date, the check shows it.
About
Gas Pro Co is a company based from the Clapham area that delivers exceptional Gas, Heating and Plumbing breakdown and repair works. We are a small company with 24 years experience in the industry that deals with all Gas, Heating and Plumbing issues at the domestic, light commercial and commercial level. We can be give you an idea of costs by phone, email or ideally through a video call. We will sure up a cost before any work is done through a quotation. Gas pro co are Gas Safe Registered and ciphe registered. You can also find us on Checkatrade for further reviews and services. We look forward to hearing from you.
Independent checks
About this business
A real, registered businessWe cross-checked Companies House: this business is officially registered for work that matches the plumber services it advertises - independent confirmation it's a genuine business set up to do this kind of work, not just a directory entry.
Recently reviewed13 reviews in the last 12 months.
Your own checks
What to check before you hire
Worth checking yourself
Always confirm credentials and quotes with the business directly before hiring.
Verify at the sourceCheck them yourself
Approved plumbers on the free WaterSafe register are vetted, qualified to the water regulations and insured. Check they're listed, or find a WaterSafe-approved plumber near you.
Check the WaterSafe registerAgree the call-out fee, the hourly or fixed rate, and whether parts are charged on top, in writing, before an emergency plumber starts. Out-of-hours overcharging and 'while I'm here' add-ons are common complaints.
Be wary of a plumber who, on a first visit, says your whole system or boiler must be replaced. Get a second opinion and an itemised quote (parts and labour separately) before agreeing to major work.
Gas and boiler work is a separate, regulated trade, not general plumbing. Make sure anyone working on a gas appliance is specifically registered to do gas work, and ask to see that registration before they start.
Want an extra legitimacy check? Run the Cowboy Checker on Gas Proco (London) Ltd before you contact them.
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Common questions about Gas Proco (London) Ltd
Is Gas Proco (London) Ltd a legitimate business?
Gas Proco (London) Ltd has 59 independent public reviews. It is a registered business on Companies House, listed as active, and the public register shows no adverse status (no dissolution, insolvency or strike-off) against it. This is independent public evidence gathered from named public sources (no ads, no paid placement), not a guarantee of workmanship. If anything here is out of date, the business can request a correction.
What do customers say about Gas Proco (London) Ltd?
Gas Proco (London) Ltd has 59 public reviews. You can read the individual reviews and where each came from in the reviews section above.
How do I know Gas Proco (London) Ltd's reviews are genuine?
Gas Proco (London) Ltd's 59 public reviews come from a named public review source, and MyTrustedTraders links every one back to where it was published, so you can open the source and read them yourself rather than trusting a single curated page. MyTrustedTraders brings this public evidence together with no ads and no paid placement: we show where every review came from rather than selling rankings, so you can weigh the evidence for yourself.
Has Gas Proco (London) Ltd had recent public reviews?
Gas Proco (London) Ltd has 13 public reviews dated within the last 12 months. That shows their review history includes recent feedback; it does not prove current availability, so confirm capacity before hiring.
Is Gas Proco (London) Ltd qualified and accredited?
We hold 1 independently sourced credential for Gas Proco (London) Ltd, including Which? Trusted Trader. Each is attributed to the body that issued it in the credentials section. For example, Which? Trusted Trader is Which? Trusted Trader: an endorsement from the consumer champion Which?, given to traders who pass its assessment process.
Is Gas Proco (London) Ltd a registered business?
GAS PROCO (LONDON) LTD is a registered business on Companies House (company number 08886484), incorporated 11 Feb 2014, listed as active. This confirms the legal registration of the business, not evidence of workmanship or service quality.
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