• Keep your home
    warm this year
    Now offering £200 off
    all new boiler installations
    Find out more
  • Warranty
    Guarantee
    All gas repairs fully
    guaranteed for 12 months
    Find out more
  • State of the art
    plumbing & fittings
    Now offering 20% off
    to fit new kitchen fittings
    Find out more
  • Keep your home
    warm this year
    Now offering £200 off
    all new boiler installations
    Find out more
  • Warranty
    Guarantee
    All gas repairs fully
    guaranteed for 12 months
    Find out more
  • State of the art
    plumbing & fittings
    Now offering 20% off
    to fit new kitchen fittings
    Find out more

Heating Engineer London

All aspects of Heating and Plumbing undertaken in London, Hertfordshire and Essex

Assert Heating Services represents the breaking edge in delivering complete gas & heating services throughout London and the surrounding areas. We are constantly building our portfolio for modern plumbing, gas and heating engineering from small to larger projects.

We were originally founded in 2003 and have been bringing innovative, specialised heating services to London and the surrounding areas ever since. Over the years we managed to gain an extensive array of experience in the plumbing and heating trade and have built up an impressive list of ongoing customers as we strive to improve the quality of residential heating systems in and around London. We are established partners and approved installers of a number of boiler manufacturers including Worcester Bosch and Vaillant.

What service are you looking for?

Assert Heating Services is a leading provider of extended heating services to homeowners and businesses in London and the surrounding areas.

What service are
you looking for?

Assert Heating Services is a leading provider of extended heating services to homeowners and businesses in London and the surrounding areas.

Gas

We offer extensive gas service solutions. From gas safety checks, gas safety certifications to gas leak repairs and other gas services in London.

Read more »

Plumbing

Our team of plumbing engineers work fast and efficiently and can carry out a range of services from routine leaks to advanced system problems.
Read more »

Heating

Our team of gas safe heating engineers carry out boiler repairs, install state of the art heating systems and implement system upgrades on a daily basis.
Read more »

Valliant Boiler Service London

We provide thorough 12 point checks on your Valliant Boiler, carried out by an expert gas safe engineer. Our Valliant boiler service in London will ensure that your Valliant boiler is working safely and efficiently. Future issues can also be spotted earlier, reducing the chances of a replacement being required.

What our customers say

We care what our customers think of us and love to hear your feedback, if you would like to know what we can do for your home or business give us a call today and we’ll be happy to help!

Charlie Findlater

Thanks Ryan, for a fantastic job on the boiler conversion for our new house, pre-refurb!

Ryan was recommended to us by a good mutual friend, to check a redundant gas pipe that was randomly sticking out of the ground in what will be our living room area and ensure the gas supply was cut off and sound and then remove the eyesore of a pipe for us.

What I really like about how Ryan works is that he’s efficient, professional and really knows his job, and is a good communicator. He always returned my calls and answered any texts/questions within a short space of time, and this to me took the stress out of the whole process. To top it off he gave me a wholesome price on the boiler conversion and kept me well informed throughout the process.

On time, professional, experienced and excellent communication. All key attributes of a fantastic tradesman! Thank you Ryan, we will see you for our annual service and maintenance and highly recommend you to all our friends and family!

Best Wishes, Nita

N McEvoy

Ryan was very polite and friendly . I would definitely use Assert heating again and due to professionalism. I would recommend them to others in the future.

Sandra Garbet

Ryan was communicative and professional. He did a great job and went out of his way to help us. I’d recommend Assert Heating. Thanks Ryan!

JulietC-37
Great service

Great experience from Ryan and his team at Assert Heating Services. Showed up on time, were friendly and professional, sorted out my boiler at a reasonable price. Would recommend.

louise osborne

Our boiler broke down a week ago and Assert were quick to respond especially given the current circumstances. great value and service, cannot thank enough.
Cheers, all the best.

Omar El-sayed

Ryan did a great job replacing my two old boilers, re-piping and installing an new eco Vaillant boiler. Arrived on time and all work completed in one day.

Spyros Spyrou

Ryan was very polite and friendly . I would definitely use Assert heating again and due to professionalism. I would recommend them to others in the future.

Sandra Garbet
J V

Great workmanship, friendly and helpful. Assert were fairly priced and trustworthy.
We had our boiler position moved as well as a new one installed. All our needs were met quickly and professionally. We will be sure to use them in the future. Can not recommend enough.

Simon Thompson

A very prompt and professional service. Highly recommended. Would definitely use again.

christian oliver

Great service, friendly and very professional. After the first email , Ryan made sure the inriial contact straight away and made all the arrangement for the appointment. He was very flexible with the timing. I have completed the gas certificate ans it was value for money . He was on time and made sure hechecked everything needed . I am definitely will be using this company again. I highly recommend assert heating services.

samira

Speedy and efficient job at a fair price. Very satisfied

richard , CM20
Gas / Heating engineer

Tennant reported that they had no hot water. I contacted AHS, Ryan, who attended, and by the next day two parts were replaced and hot water was up and running. All were happy with the great service provided

Brendon Ladd
Juliet Cochrane

Assert Heating provided a very professional service, very clean and tidy i would recommend them 100%

Ahmet Djemal

Great service Ryan. Arrived on time, very friendly & sorted out the boiler problem efficiently. We’d definitely recommend your services.

Leroy Pitt

Great workmanship, friendly and helpful. Assert were fairly priced and trustworthy.
We had our boiler position moved as well as a new one installed. All our needs were met quickly and professionally. We will be sure to use them in the future. Can not recommend enough.

Simon Thompson

Very professional and fixed the issue with minimum fuss.

Bishu Debroy
Adrian Geaves

Contacted Assert Heating Services upon recommendation due to no heating or hot water at home. Within 24 hours Ryan attended, he was able to identify the issue and advise to cost and parts needed. Friendly, reliable and efficient service provided. Completed job to a high standard, will definitely use services again – highly recommended!

SelC
Fast, efficient, reliable and quality service !

A very prompt and professional service. Highly recommended. Would definitely use again.

christian oliver

Cant recommend this guy enough, Assert Heating Services provided a great service during this difficult time. Ryan was professional and clear about the problem I had with my boiler. He took the time to talk me through and show me where the issue was. I didnt feel harrased, he let me think about replacing the boiler before I called him in to do the job. All in all, great job and I now have hot water again. Highly recommend.

helen georghiou
Katharine Walker

I’ve used Assert a few times now and each time I was impressed with how they conduct themselves before the job, during and after. The most recent experience was with Ryan who quoted me to replace a diverter valve on my very expensive Vailant boiler. Due to how much water was in the boiler which had to be drained, the job took a couple of hours but that had no bearing on the price or the professionalism whilst in my house. I know from experience others would have milked me for more money so I was pleased that again I paid the job quoted for and I definitely got what I paid for. Great experience with Assert and have no hesitation recommending them.

AndyC-2432
Quality work, honest price and very professional

A very prompt and professional service. Highly recommended. Would definitely use again.

christian oliver

II was very pleased with Ryan he was polite and professional and punctual and I would highly recommend the service
Kind regards
Mr D Webb

DannyW-237
Assert heating
Khalid Fahfouhi
Katharine Walker

Good price and good service. Maintenance is very fast.

Song Helen

Thanks to Ryan for punctually arriving at my mum’s and quickly sorting boiler issue. My mum would have been without water and heating otherwise. Great value callout and great quality work. Will be using Assert every time now for future work. Chris

Chris Steele

Top professional service, they saved me and my family when our boiler stopped working, we didn’t have to wait long at all for them to come down and sort it, will definitely be using them again, i highly recommended.

Adam Smith
Senake Hettiarachchi

Our boiler broke down a week ago and Assert were quick to respond especially given the current circumstances. great value and service, cannot thank enough.
Cheers, all the best.

Omar El-sayed

Fantastic service. I called the company to help in an emergency and they promptly arrived at the property and quickly identified the problem. Ryan was very knowledgable and understanding and we felt confident in his hands.
Thank you so much for a fabulous service

KatieM-592
Fantastic service

Assert Heating provided a speedy service. Very professional and polite engineer who respected social distancing. Will definitely use again. Fully recommend

Elena Kounis Sophocleous

I phoned needing an emergency repair to my heating system and booked in a visit on the phone. Ryan was polite, on time and professional. He diagnosed a fault with my boiler and explained how to rectify it and what that would entail. We agreed there and then for the remedial works to be done. Ryan attended again with parts to fix my boiler and had my heating and hot water up and running again in no time. I have already booked another appointment to have my boiler and both gas fires serviced in a few months time. Both happy and relieved, I have finally found a reliable plumbing and heating engineer!

Rebecca C

Great service, friendly and very professional. After the first email , Ryan made sure the inriial contact straight away and made all the arrangement for the appointment. He was very flexible with the timing. I have completed the gas certificate ans it was value for money . He was on time and made sure hechecked everything needed . I am definitely will be using this company again. I highly recommend assert heating services.

SamiraA-20
Professional, friendly and value for money
Adrian Geaves

Been using Ryan for all my heating and gas needs over the years.
He’s always prompt and carries out a good job.
Highly recommended.

Eric Ibekwem

Great experience with Assert, can’t thank enough!

charlotte baird

Thanks Ryan, for a fantastic job on the boiler conversion for our new house, pre-refurb!

Ryan was recommended to us by a good mutual friend, to check a redundant gas pipe that was randomly sticking out of the ground in what will be our living room area and ensure the gas supply was cut off and sound and then remove the eyesore of a pipe for us.

What I really like about how Ryan works is that he’s efficient, professional and really knows his job, and is a good communicator. He always returned my calls and answered any texts/questions within a short space of time, and this to me took the stress out of the whole process. To top it off he gave me a wholesome price on the boiler conversion and kept me well informed throughout the process.

On time, professional, experienced and excellent communication. All key attributes of a fantastic tradesman! Thank you Ryan, we will see you for our annual service and maintenance and highly recommend you to all our friends and family!

Best Wishes, Nita

N McEvoy

Thank you to Ryan at Assert Heating, he completed boiler service but noticed we had an issue with a leaking tap which we were waiting for a plumber to come and fix in a few days time but Ryan offered to cap it for us to save us money on our water bill. I would definitely use again and recommend.

Anthony Arbon

Thank you to Ryan at Assert Heating, he completed boiler service but noticed we had an issue with a leaking tap which we were waiting for a plumber to come and fix in a few days time but Ryan offered to cap it for us to save us money on our water bill. I would definitely use again and recommend.

Anthony Arbon

Assert Heating provided a very professional service, very clean and tidy i would recommend them 100%

Ahmet Djemal

Thank you Assert Heating for your very quick response. Boiler issue was sorted quickly and professionally. Your engineer was polite and respectful of social distancing, wore gloves and mask. Fully recommend!

Elena Sophocleous

Thanks to Ryan for punctually arriving at my mum’s and quickly sorting boiler issue. My mum would have been without water and heating otherwise. Great value callout and great quality work. Will be using Assert every time now for future work. Chris

Chris Steele
back beat
David Wolgroch

Lee was super helpful and fast at fixing our heating!

Billie-rose Dell
Adrian Geaves

Great service, friendly and very professional. After the first email , Ryan made sure the inriial contact straight away and made all the arrangement for the appointment. He was very flexible with the timing. I have completed the gas certificate ans it was value for money . He was on time and made sure hechecked everything needed . I am definitely will be using this company again. I highly recommend assert heating services.

samira

Ryan from Assert Heating Services came yesterday to do a full heating check. He was very knowledgeable and also suggested changing an old radiator to improve heat retention in a cold room. We’ll definitely have Ryan back to fit the new radiator and for future heating checks. I’ve already recommended Assert Heating services to a friend!

Lucy Simler
Senake Hettiarachchi

Thank you to Ryan at Assert Heating, he completed boiler service but noticed we had an issue with a leaking tap which we were waiting for a plumber to come and fix in a few days time but Ryan offered to cap it for us to save us money on our water bill. I would definitely use again and recommend.

Anthony Arbon

Ryan was friendly, efficient and knowledgable. He serviced our Worcester Bosch boiler today.

Brian , NW11
Gas / Heating engineer

I had a boiler installed recently and would recommend their services! Reliable, honest and competitively priced.

Lyndsey Page

We have used Ryan for a few jobs over the years. Always provides a good service and cleans up after. Highly recommend him.

Maria Apostolou

Very good service and efficient .. they responded fast and it didn’t take much time to know what’s the problem and to fix it.
Thanks to Rayen and his team I highly recommend them

Mohamed Salem

Lee was super helpful and fast at fixing our heating!

Billie-rose Dell
Senake Hettiarachchi

Assert Heating were responsive, quick to make an appointment and carried out the work professionally and cheerfully! I would recommend!

Mika Nash

Our boiler broke down a week ago and Assert were quick to respond especially given the current circumstances. great value and service, cannot thank enough.
Cheers, all the best.

Omar El-sayed

Really good work very professional.

KenK-37
Excellent

Fantastic service! Quick response, boiler issue sorted quickly. Highly recommended.

tom370

Ryan from Assert Heating Services arrived at the time promised and carried out the job very professionally and left the place spotless. Would recommend Ryan and his company for prompt and professional services without compromise. I have booked Ryan for annual boiler service which will be carried out this week.

Dinesh Sudra

Ryan was very polite and friendly . I would definitely use Assert heating again and due to professionalism. I would recommend them to others in the future.

Sandra Garbet

Fantastic service! Quick response, boiler issue sorted quickly. Highly recommended.

tom370

Thank you Assert Heating for your very quick response. Boiler issue was sorted quickly and professionally. Your engineer was polite and respectful of social distancing, wore gloves and mask. Fully recommend!

Elena Sophocleous

Great service, friendly and very professional. After the first email , Ryan made sure the inriial contact straight away and made all the arrangement for the appointment. He was very flexible with the timing. I have completed the gas certificate ans it was value for money . He was on time and made sure hechecked everything needed . I am definitely will be using this company again. I highly recommend assert heating services.

samira

Thanks Ryan, for a fantastic job on the boiler conversion for our new house, pre-refurb!

Ryan was recommended to us by a good mutual friend, to check a redundant gas pipe that was randomly sticking out of the ground in what will be our living room area and ensure the gas supply was cut off and sound and then remove the eyesore of a pipe for us.

What I really like about how Ryan works is that he’s efficient, professional and really knows his job, and is a good communicator. He always returned my calls and answered any texts/questions within a short space of time, and this to me took the stress out of the whole process. To top it off he gave me a wholesome price on the boiler conversion and kept me well informed throughout the process.

On time, professional, experienced and excellent communication. All key attributes of a fantastic tradesman! Thank you Ryan, we will see you for our annual service and maintenance and highly recommend you to all our friends and family!

Best Wishes, Nita

N McEvoy

Very good service. On time friendly & efficient.
Leroy Pitter

LeroyP-6
Boiler repair. Excellent service

Ryan from Assert Heating Services arrived at the time promised and carried out the job very professionally and left the place spotless. Would recommend Ryan and his company for prompt and professional services without compromise. I have booked Ryan for annual boiler service which will be carried out this week.

Dinesh Sudra

Highly recommended local boiler service. Prompt, Respectful. Didn’t just come in to do the job but gave sound advice on the equipment and how to avoid incurring long term cost. Friendly and good customer service

NickA-280
Great Service

Great experience with Assert, can’t thank enough!

charlotte baird

Prompt reply, smooth communication.

khalid , E17
Gas / Heating engineer

Great service Ryan. Arrived on time, very friendly & sorted out the boiler problem efficiently. We’d definitely recommend your services.

Leroy Pitt

Lee was super helpful and fast at fixing our heating!

Billie-rose Dell

Fantastic service! Quick response, boiler issue sorted quickly. Highly recommended.

tom370

Great experience with Assert, can’t thank enough!

charlotte baird

Ryan came to conduct a boiler service. He was punctual and informed me of his ETA prior to arriving. Showed me ID on arrival. Super polite and professional. Very knowledgeable. Respectful of COVID rules. I would highly recommend this trustworthy service. Thank you!

Claire Cortez

Cant recommend this guy enough, Assert Heating Services provided a great service during this difficult time. Ryan was professional and clear about the problem I had with my boiler. He took the time to talk me through and show me where the issue was. I didnt feel harrased, he let me think about replacing the boiler before I called him in to do the job. All in all, great job and I now have hot water again. Highly recommend.

helen georghiou

Recently used Assert after my usual plumber couldn’t come out quick enough for a burst pipe in one of my properties and am very glad I did. Assert were quick to respond and fixed the issue to a high standard in next to no time. Great service all round. Looks like Assert might be my new port of call for any emergencies.

DominicFirthProperty
Quick and professional during an emergency.

Cant recommend this guy enough, Assert Heating Services provided a great service during this difficult time. Ryan was professional and clear about the problem I had with my boiler. He took the time to talk me through and show me where the issue was. I didnt feel harrased, he let me think about replacing the boiler before I called him in to do the job. All in all, great job and I now have hot water again. Highly recommend.

helen georghiou

Very quick, clear communication, highly recommend

Alastair , E17
Gas / Heating engineer

Professional, efficient and friendly with lots of good advice – identified problem and fixed leak leaving everything clean and tidy – would highly recommend.
John & Marion London N11

MarionB-105
Highly recommend Assert Heating Services

I have used Ryan a couple of times and he is very professional knows his stuff no job to big or small he has every part needed for the job I can’t recommend him enough and will be passing his details on to friends and family and will not hesitate to call him again if I have anymore problems
a big thank you for reconnecting my cooker again
Grateful customer

Lele Williams

We called Ryan on a recommendation to look at our hot water system which had stopped working. Ryan came as soon as he could and though the problem was a mystery he figured it out quickly and came back the next day with the right parts to fix. He was efficient, courteous and helpful. His price was fair and we will use him again. Thanks Ryan. Ina Norrman

Ina Norrman

Ryan carried out a service on our gas boiler and was very helpful and efficient.

BrigitteE-1
Gas boiler service

Thank you Assert Heating for your very quick response. Boiler issue was sorted quickly and professionally. Your engineer was polite and respectful of social distancing, wore gloves and mask. Fully recommend!

Elena Sophocleous

Great workmanship, friendly and helpful. Assert were fairly priced and trustworthy.
We had our boiler position moved as well as a new one installed. All our needs were met quickly and professionally. We will be sure to use them in the future. Can not recommend enough.

Simon Thompson

Ryan from Assert Heating Services arrived at the time promised and carried out the job very professionally and left the place spotless. Would recommend Ryan and his company for prompt and professional services without compromise. I have booked Ryan for annual boiler service which will be carried out this week.

Dinesh Sudra

Great service Ryan. Arrived on time, very friendly & sorted out the boiler problem efficiently. We’d definitely recommend your services.

Leroy Pitt

Assert Heating provided a very professional service, very clean and tidy i would recommend them 100%

Arms Djemal
Laurence Hussey

Thankyou Assert Heating for repairing our boiler. Your services were very professional.

G Dhanji
Character and story-driven cinematic imagery.
Plumber in London