Frequently Asked Questions


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Frequently Asked Questions about our services, boiler repair, boiler installation, our heating services, and what we can do for landlords. Can’t find your question? Call us at 0207 0999 035

FAQs about Boiler Repair & Installation

Yes, we try to attend all emergency boiler repairs and heating repairs the same day we receive your enquiry. 

If we have no scope we will offer you the next available appointment, unlike some of our competitors we will never book an appointment we know we are unable to honour just to keep your custom.

It’s hard to say, every boiler or heating repair is different.

If you don’t need any parts replaced or major work it could be very quick and repaired for just £95+vat, also some boiler parts are easy to fit and can be diagnosed and replaced within an hour.

The diagnostic fee is a fixed fee depending on the time and day we visit, if it takes 5 minutes or 5 hours the fee you pay remains the same.
In some instances such as low water pressure or air trapped in radiators your engineer may be able to diagnose and repair the fault within 30 minutes without any additional parts and you’ll only need to pay the diagnostic fee.

Yes, all of our engineers have a significant van stock to carry out boiler repairs and heating repairs in one visit carrying many universal parts to repair your heating system including smart thermostats,  TRVs, zone valves etc.

We also carry specific parts for Vaillant boiler repairs and other manufacturers, it’s impossible for us to carry every part we might need to do a boiler repair or heating repair but we stock the parts we use most regularly to give us the best chance of repairing your boiler or heating system in one visit.

Sometimes, we’ve spent a long time building connections with reputable suppliers who offer enforceable guarantees and warranties.

If you supply your own materials and something goes wrong, we will have no means to enforce a replacement on your behalf.

Get in touch and we’ll send someone back.

Even if the fault is low system pressure or after an annual boiler service which are usually excluded from our guarantee if we find the problem is due to work we’ve carried out in the last 12 months we’ll put it right free of charge, if not we’ll issue you a quote for the repair.

The cost of a new boiler installation varies depending on lots of things including which model is best suited for your needs or how much additional work is needed.
Usually between £2000 – 4000 it can be more if we’re installing a new heating and hot water system along with the new boiler.

Yes, anything that was part of the old system including radiators, cylinders and pipework will be removed, treated and recycled using government approved centres.
Any household items such as old cupboards or shelves which needed to be removed will be your responsibility as the centres we use only accept commercial waste.

Not during the actual installation of the boiler and heating system. If you’re having more work done and the job is expected to last more than one day we will always leave your cold water on as a minimum and supply electric fan heaters if requested.

It really depends on the amount of work we’re carrying out, generally a like for like boiler swap should take 1 day. If we’re moving the boiler to a new location it could take 2-3 days and if we’re installing a whole new heating and hot water system it could take up to 5 days.

Your engineer will explain how much work is required and an expected time scale during your survey so you can be prepared.

When the engineers have finished installing the new boiler they’ll check to make sure everything is working correctly before handing over the controls to you.

They’ll then run through how your new boiler and system work and answer any questions you may have. 

Over the coming days you’ll receive various emails containing information about your guarantee and registration, keep these safe.

Remember, we’re here to support you long after the initial installation so if you have any questions after we’ve left just get in touch and we’ll be happy to help. 

FAQs about the quote & diagnostic fee

No not all jobs, for large jobs like boiler installations or system upgrades we offer a free no obligation estimate.
For work where we need to diagnose a fault such as boiler breakdowns or leaks, we charge a diagnostic fee from £95+vat depending on when we visit, if we can’t diagnose your boiler fault or heating fault we’ll pay you double the diagnostics fee.
Other jobs including an annual boiler service or landlord gas safety certificate have fixed prices that can be found on our prices page.

As a general rule if your engineer needs to use their tools during your visit it’s classed as work and a fee from £95+vat depending on the time and day we visit will be charged.
During the diagnostic process if your engineer can repair the fault within 60 minutes without the need for any parts then there’ll be no additional charge, if more time or parts are needed your engineer will provide you with a fixed price quote.

Every new boiler we install includes a highly experienced Gas Safe registered engineer, 12 months workmanship guarantee, 7 – 12 year manufacturer guarantee, a magnetic system filter, new energy efficiency compliant controls, a deep system magnacleanse using Fernox F3, F5 and F1 chemicals, registration with the manufacturer, Gas Safe and your local authority, a gas safety certificate, annual service reminders for the duration of your guarantee.

FAQs about guarantees

All of our new boiler installations include a 7 – 12 year manufacturer guarantee and our own 12 month workmanship guarantee.
Our boiler repairs also include a 12 month workmanship guarantee and a manufacturers guarantee on parts which is usually 12 months.
Low system pressure and annual boiler service / CP12 are usually excluded from the guarantee.

General Questions

Yes, all of our work is covered for accidental damage up to £5,000,000


A guarantee you can rely on

Are you constantly being told that your boiler’s too old to repair, inefficient and you need a new boiler?

It’s probably nonsense. Everything can be repaired and nearly all parts can be sourced if you know where to look and who to ask.

We’ve built a network of trusted suppliers in and around London for both new and reconditioned boiler spares with enforceable guarantees giving you the maximum opportunity for success with guaranteed peace of mind.

Our boiler repair services in includes:

Discover higher standards

All of our boiler repair engineers are trained and accredited by the two leading names in heating, Viessmann and Vaillant. That means we’ve been trained to a higher standard than most and continually maintain a level of service that’s guaranteed to fill you with confidence.

Vaillant Advance boiler logo

Tried, Trusted, Reviewed

The Heatsy promise:

“We promise to always give 100% in our efforts to help you in your time of need, to never take advantage, overcharge or give you unnecessary advice.

To keep our charges fair, competitive and 100% transparent while keeping our service above and beyond by using only fully vetted, qualified, experienced and skilled tradespeople.

Should you ever have a query about the service you have received, the price you were quoted, or the work we have completed, we promise to treat the situation with the seriousness it warrants and give you the dignity, respect, and honesty you deserve." 

Mr Lee Moloney

An emergency boiler repair in action

At Heatsy we specialise in repairing old and new boilers by all manufacturers, we offer a 24/7 same day response service.

All our work is guaranteed and if we can’t diagnose the fault we’ll pay you double the diagnostics fee.

Watch the video and see why we insist on powerflushing 90% of our installations.


Run by our family, for your family

All Heatsy boiler repair engineers have at least 5 years of experience in the heating industry.
All of our installations and boiler repairs come with an iron-clad 12-month guarantee.

We charge an initial diagnostics fee from £95+vat and if we can repair the fault with in the first hour without any parts then that’s all you’ll pay.

If any parts are needed we’ll often be able to save you money by offering you the option of using reconditioned parts with a 12-month guarantee from the network of suppliers we’ve built up over time.

We offer a 24 hours a day, 7 days a week emergency boiler repair service in and around LONDON.

If you need your boiler or heating system repaired contact us now on :
0207 0999 035 or

Our Google Reviews

Heatsy IconHeatsy

Heatsy Ltd, 4 Selsdon Crescent, South Croydon

4.9 67 reviews

  • Avatar Sheshebens Algonquin ★★★★★ 3 months ago
    Heatsy completed our boiler repair quickly and efficiently.
    We called at 12pm and were offered two appointments, 4-6pm that evening or 8-10am the following morning at a lower rate.
    … More As it’s winter and mom was visiting from the US we decided to get the emergency appointment.
    The engineer called and text before he arrived and kept me updated throughout the work.
    Coming from the states we’re used to great customer service and I must say Heatsy made me feel right at home.
    Your slogan should be ‘British class with American service’
    I’ll be telling all the other moms at the next PTA meeting 😊
  • Avatar Zacharie Paimboeuf ★★★★★ 3 months ago
    Great boiler service, the engineer took everything apart and cleaned the inside and changed the seals.
    He also took a water sample from the boiler which showed the system was dirty
    … More and he was able to book me in to get my system cleaned without me needing to do anything.
    Very helpful and professional.
    Thank you
  • Avatar Sarah Luetchford ★★★★★ a month ago
    Was extremely helpful and explained what needed doing and was honest about what I needed to consider. Once he had finished and I messaged with an enquiry my engineer offered to come … More back and have a look. They sent a follow up message to ensure everything was still working and to check it was ok. Would definitely use again.
  • Avatar Martin Gilbert ★★★★ 3 months ago
    I had a combined boiler service with landlords gas safety certificate.
    The company were very professional and my tenant was very happy with the engineer.
    All paperwork and certificates
    … More were emailed in real time and I could track the engineer which is a nice touch.
    Four stars as the appointment had to be rescheduled due to over running work.