A large team of qualified Corgi registered heating engineers and a team of dedicated service personnel, 23 hour service Leakbusters are London's favourite Central heating specialist. With Leakbusters you buy peace of mind and a trouble free installation experience - we're always on call and you will always receive a personal response day or night.

Your New Boiler is the most important Appliance in your home; invest in the best within your budget.


How much should a new boiler cost?

Almost every day we receive calls asking for a boiler quote, 'just give a rough price' 'it is a simple swop' or 'I won't hold you to it but just give a rough estimate, you install boilers every day so you must know how much?'.
Although there is an element of truth in each statement, installing a new high efficiency boiler or 'condensing boiler' as they are commonly known is far from simple.
Unfortunately, the simple 'boiler swap' no longer exists. Not legally anyway. Fitting a new boiler means complying with plenty of restrictive rules, regulations and instructions, and many of these are EXPENSIVE to observe. The net result is that our quotation for a fully compliant replacement boiler makes us look more expensive, than other installers that are willing to take short cuts to secure the job.
We install in excess of 300 boilers a year and we repair significantly more in number, this means our engineers are experienced in knowing which boilers break down the most, what are the 'weak spots' within a boiler and when choosing a new boiler, what to steer well clear of and what to buy.
Installers are no different to the public and they too have brand loyalties. Over the years we have installed many different brands; however the simple rule we follow is

What boiler is best for our customers needs?

Which boiler will offer the best return on the customer's investment?

Which manufacturer will not only offer a long parts and labour warranty, but will honour it*?

*it is common practice for manufacturers to look for ways to not honour there warranty, by looking for external system faults that have no relation to a boiler fault. We know who these manufacturers are and will NOT install there products.

It is our considered opinion that the German manufacturers such as Worcester Bosch and Viessmann have got there act together and offer outstanding value.

Back to the question of Cost

1) Condensing boilers are compulsory under the Building Regulations in most situations. They cost 100-200 more to buy than their non-condensing equivalent, and they also need a drain connection to carry away the condensate they produce. This can be trivial to install or a major task adding a day or more to the work. Sometimes moving the boiler to a different location in the house is the only way to achieve the drain connection. All this is avoided by ignoring the Building Regulations and fitting a non-condensing boiler*.

*There are special exemptions in the Building regulations that allow for a non-condensing boiler to be installed in exceptional circumstances.

2) 'Energy-efficient' controls are now compulsory under the Building Regulations. Most existing boilers are half way there with thermostatic control of both heating and hot water but separate temperature control of the sleeping areas is now required. This can be achieved by fitting thermostatic radiator valves in the bedrooms, but conversion to 'fully pumped' pipe work format is necessary unless already installed.

3) A new gas supply pipe is usually necessary to comply with the latest HSE and CORGI guidelines on permissible pressure drops between the gas meter and the appliance. We are now allowed only 1mbar pressure drop, and this means most existing gas supply pipes are too small. A new boiler will usually work perfectly well connected to the existing pipe with a pressure drop of 3 or 4 mbar, but to comply with this new guidance a new, larger gas supply pipe usually has to be installed all the way from the meter to the new boiler. When boiler and meter are on opposite sides of the house this can add days of work, without even taking into account re-instatement of disrupted decorations etc. Customers often say why you don't just connect up to the existing gas pipe, I had another quote and the engineer never mentioned anything about the gas pipe size. It is true that if we connect up to the existing pipe the boiler will work, however the boiler may NOT WORK TO ITS FULL POTENTIAL. You will be purchasing a superdooper Band A high efficient boiler that may not operate at its maximum efficiency, it's a bit like buying a Lamborghini* and only driving it in 3rd gear, the car will work but not to its real potential. *Believe it or not Lamborghini actually make gas central heating boilers in Europe
Potential cost saving by re-using existing gas supply pipe and not installing the appropriate gas pipe as stipulated by the manufacturer and regulations: 0 to 1,000

4) Power flushing. Virtually all boiler manufacturers demand their boilers are connected to clean heating systems, and decline to accept warranty claims for failures caused by sludge or corrosion deposits in the circulating water. This means cleansing the existing radiator system before connecting the new boiler. Powerflushing is the usual way to carry out this process.
Cost saving by not powerflushing (including chemicals): Around 60 per radiator. 480 on a typical eight-rad system.

5) Electrical wiring in kitchen. The Building Regulations* effectively require all wiring in kitchens (apart from repairs) to be carried out by qualified electricians. Very few CORGI heating engineers are formally qualified to carry out electrical work so compliance means employing a separate electrician to connect up the boiler if installed in the kitchen. The problem with employing an electrician is that he will insist the installation is brought up to current safe electrical standards, while the plumber would have just put the same wire that fed the old boiler back into the new one. *We are qualified Part P of the Building Regulations, this means we can carry out the electrical work ourselves without having to engage the services of 3rd parties.
Probable cost saving for NOT employing electrician, 100 to 400.

6) Pump over-run wiring. Condensing boilers have a device built into them to control the pump, keeping it running for a few minutes after the burners have shut down (to distribute the residual heat and protect the fragile high-performance heat exchanger, in case you were interested). This means running an extra cable from the boiler location to the pump location (usually next to the hot water cylinder upstairs in the airing cupboard). Installing this extra cable can be time consuming and disruptive to carpets and decorations. Fitting certain non-condensing boilers instead sidesteps this requirement, or the customer probably wouldn't notice if the installer didn't bother to connect up the pump over-run (until the heat exchanger fails a year later, that is).
Possible cost saving for not installing pump over-run wiring: 100 to 1,000.

7) Post-installation cleansing and corrosion inhibiting. Central heating systems slowly corrode on the inside unless corrosion inhibitor is added to the circulating water, creating a black sludge that blocks heat exchangers, radiators, pipes, and generally causes a variety of problems. A dose of decent quality inhibitor costs around 15, but leaving it out won't show up for many years, by which time the name of the offending installer will have been long forgotten. The corrosion effect is accelerated if the 'post installation cleanse' is missed out. This is a quick cleanse to remove the flux residues left by the soldering process used in the installation of the new boiler pipe connections. Again, no-one will know if it is skipped, until a few years later when the corrosion problems begin early.
Possible cost saving for leaving out the post installation cleanse and corrosion inhibitor: around 100.

8) Gas Work Notification. This is a compulsory 'service' introduced by CORGI. Gas engineers are now obliged to provide CORGI with details of every gas appliance installed, along with other information including the customer name and address. CORGI then undertake to provide the customer with a document certifying that the work has been carried out in accordance with the Building Regulations. This document supposedly becomes part of the 'Home Information Pack' (HIP) and may be required when you sell the property. However, the real reason for Gas Work Notification is to allow CORGI freedom to select jobs for inspection. If you don't receive the CORGI certificate, then your installation probably wasn't notified because some of the shortcuts listed above were taken.

9) Which make should I choose, ask 10 engineers and you will get 20 different answers. It is possible to buy a condensing boiler for 400, however a cheap boiler will NOT be the same as branded 750 boiler, if it was as reliable, as efficient and as good as the more expensive branded boiler, we all would have one in our homes (and the more expensive boiler manufacturers would be left scratching there heads wondering what had happened).

10) There are plenty of other short-cuts, but these are the primary and most common ones.


Back to how much is my new boiler going to cost?

As you can see from just some of the considerations mentioned above, it is nearly impossible to quote a 'rough' or 'fixed ' price based on the strength of a telephone conversation.
We would be delighted to attend your property at a time* that is convenient to you in order to assess and understand your heating needs and advise you on the appropriate boiler and controls that are within your budget.
*Crazy as it sounds; we literally will do this at any time. Some of our customers are city workers and have requested boiler quotes at 3am; all we ask is that you have the kettle when our engineer arrives


Although many homes are similar, certanly lifestyles are not. Simply put we promise to offer you the following:

- Best Value
- Best Products

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