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Sleeman Heating Limited

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4.9

20 Reviews

About

Hi – I m John Sleeman.

My company installs energy efficient German and Dutch condensing boilers, and solar panels and we specialise in heating installations in North and Central London.

Aims

To offer competition to the large heating companies who seem to charge a high price for services that are adequate but unexceptional. I aim to provide a good quality service at a competitive price.

I offer good technical knowledge of central heating, plus the ability to design systems that conform to the best modern standards. Good communication with customers is important to me, as is the continued good operation of my installations. I offer a 2 year guarantee on my workmanship and the boilers I install are covered by guarantees on parts and labour , some of them for 5 years. I use only responsible and competent co workers.

Services provided

Boiler replacement

Complete Heating Installations

Unvented hot water systems

Solar powered hot water

What we do

  • Boiler, central heating and gas engineers

    • Boiler installation
    • Boiler repair
    • Radiators and central heating
    • Boiler servicing
  • Renewable energy

    • Solar water heating
  • Heating contractors

    • Central heating systems (installation and servicing)

Customer reviews

4.9
20 reviews
Customer Service
5.0
Quality
4.9
Value
4.9
Sort by
Replace the old boiler with a water tank for a Vaillant combi boiler
Customer Service
Quality
Value
It was nice and easy to work with John, very professional and tidy work, useful advice, all the quotations and estimations came to be right, very happy.
Customer in Greater London Posted on 28/10/2019 , work completed 27/10/2019
Excellent all round
Customer Service
Quality
Value
John fitted a new boiler for us: we're extremely happy with the work and would highly recommend him. He was extremely easy to work with, gave us some excellent advice regarding the choice of boiler (we've ended up with a much better solution: the two other heating engineers we got quotes from simply suggested run of the mill systems; John took time to understand our needs and requirements, and proposed something that really suited us). The two-day job was performed efficiently, tidily and courteously, and John was very accommodating dealing with some unexpected issues with our gas supply. His quote was also very competitive and we're delighted to have found someone who we would have no hesitation going back to for future work.
Daniel Posted on 08/07/2019 , work completed 08/07/2019
Highly recommended
Customer Service
Quality
Value
John fitted two central heating boilers and recommended a product that was perfect for our requirements. Reliable and thorough and highly recommended.
Customer in Greater London Posted on 13/03/2019 , work completed 06/03/2019
Highly recommended
Customer Service
Quality
Value
John installed a new boiler for us. We are very pleased with his work, he is highly professional. He also undertook some unscheduled work for which we are grateful.
Breege, London Posted on 13/06/2018 , work completed 13/06/2018
Excellent job
Customer Service
Quality
Value
Installed unvented hot water system, neat job, absolutely no problems. Inspires confidence.
Gudrun, London Posted on 01/05/2018 , work completed 01/05/2018
Professional & competent
Customer Service
Quality
Value
Very thorough. Took longer than expected, but the explanation was acceptable.
Matthew, London Posted on 14/06/2017 , work completed 14/06/2017
Reliable, professional
Customer Service
Quality
Value
Great job for renewal of entire heating system, no problems with new boiler and great savings from solar hot water system.
Oliver, London Posted on 09/06/2017 , work completed 09/06/2017
Fixed a complicated issue.
Customer Service
Quality
Value
We had numerous people try to identify our plumbing issue, and John was the only one able to do so. He then came back to implement the solution and worked 2 x 12 hour days, and left the house tidy. Very impressed.
Ruth, London Posted on 06/06/2017 , work completed 06/06/2017
Very happy - super fast work
Customer Service
Quality
Value
Extremely fast and efficient service. My existing boiler was on its last legs. Phoned John on Tuesday, he came to have a look on Wednesday, gave me a quote on Thursday and fitted the boiler on Monday! Less than a week from start to finish. Boiler was installed in one day by John and Marko, both are very friendly and professional and even cleaned up afterwards. Definitely recommend!
Philip, London Posted on 08/05/2017 , work completed 08/05/2017
Expert, friendly heating engineer
Customer Service
Quality
Value
John Sleeman put twice a new boiler into my premises. He gave very good advice, took time to explain everything and was efficient with good time management. I have no hesitation to recommend him to further customers.
Angelika S Posted on 16/09/2016 , work completed 16/09/2016