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Domestic & Commercial Solutions

Our creative solutions in air conditioning, refrigeration, ventilation, heating and electrical services cater for both the domestic and commercial sectors, and we pride ourselves in providing the best result for you.

What Our Client say


You are one of the most efficient contractors I have come across and we need this approach with our quick turnaround projects in London!

Matthew Bell - Mitsubishi Electric UK

Just wanted to send a quick email to say thanks very much to you and your engineers for finally sorting out our air con issues. I think this is the first time since I started here in January 2011 that the systems have been working fault free! Hopefully I haven't jinxed it by sending this but thank you.

Jo Secker - Fisher Meredith LLP

We have been using Crystal Sigma for over 5 years...they do all our new installations of new restaurants and maintenance for all existing sites...they have always been efficient and professional and get the job done. The main advantage of Crystal is they employ their engineers rather than sub-contract the whole job out. We deal with Samir...he is very good and has an understanding of air conditioning and is hands on which gives us comfort as he knows what he is talking about and is not just a salesman. How you deal with the problems is, in my definition, whether a company is any good or not. To give you an example our AC went down Saturday night and we had an engineer with us Sunday morning and were fixed before we opened.

Suhail Hasan - MD Tinseltown Groups of Companies

Just wanted to say thank you for the successful installation of our air conditioning. We are very pleased with it. We would also like to make a special commendation for Jamie and his helper Nabil. He was an all-round excellent and very hard working engineer. Please pass on our thanks and appreciation to him also.

Angela Chow

We have employed Crystal Sigma for a period of five years now and have found them to be always very reliable, punctual and complete the installations within the agreed programme dates. Their installations are always clean and tidy, with a courteous manner to our clients at all times. Crystal Sigma always liaise with the clients informing them when they are leaving site whether this be to collect materials or for finishing for the day.

Terry Cooper - Director Argonaut Heating Limited

Many thanks for doing such a great job – if you ever need any recommendations etc. be happy to give them. All the best and thanks again for doing such a great job – couldn’t be happier.

Christian Abletshauser - Partner Meadows Fraser LLP

Crystal Sigma has worked in various housing and education projects for us over their time with us as certified subcontractors. Their approach to their work has always been professional and time limits seem to be no problem for them to achieve.

I would recommend them as subcontractors to other companies and have done in the time that they have worked with us, and I look forward to working with them again on more of our projects in the future.

Patrick Mangan - Apollo Education

I should put on record how happy we have been with your company's level of service. From your initial site visit, to Samir's follow ups and Jamie’s installation, we have been dealt with openly, honestly and with friendliness. In my experience of property renovation this is a rarity in central London. You turned up when you said you would and delivered the final product according to budget.Thanks for everything.

Glen Daly and Pauline Lafferty

Crystal Sigma installed a home air conditioning system in certain key rooms of our property in Wimbledon. I cannot speak highly enough of the quality of the work performed.

From the initial consultation, through to the final sign-off of work I had total confidence in their advice and the quality of the work. The full service offered by Crystal Sigma is what appealed to me as a busy person, not being able to coordinate multiple contractors. The initial consultation gave me full confidence in their technical abilities and a full explanation of the pros and cons of the system I was selecting was honest and enabled me to make decisions. The workmen were all exceptionally friendly, helpful and courteous. The respect with which they treated our property – keeping it clean, tidy, protecting furniture etc. was of a calibre I have yet to see in other contractors.

We were so impressed with Crystal Sigma that we have used them again to replace our central heating boiler.

Mark Baillache - KPMG

Crystal have undertaken numerous works for us in both our tenanted office and warehouse facilities: I would like to highlight our satisfaction with the level of service we have received. They have provided us with a quick, cost effective and efficient service throughout the years. Their professional attitude towards the work they have carried out has proven to be invaluable to us.

Martin McDonagh - General Manager M.P Moran & Sons