Family-run in Leighton Buzzard since 2006

Boilers fitted, serviced and repaired across Leighton Buzzard by a Gas Safe engineer who started with British Gas in 1999.

All work is discussed and agreed upon upfront for complete transparency. We leave every home clean and tidy, and we offer fast, no-obligation estimates with flexible scheduling, including evenings and weekends.

Call 07775 881505 Email us

Gas Safe registered 228490 · Worcester Bosch & Vaillant accredited · Office 01525 371939

A new white combi boiler we fitted inside a timber cupboard, with neat pipework below — Flame onGas Safe 228490

Over 25 years of experience, kept at the right pressure.

Your local Worcester Bosch & Vaillant Accredited installer

Gas Safe registeredRegistered business number 228490
Trained by British GasAnd holding City & Guilds qualifications
Up to 12 year guaranteeParts and labour on selected Worcester Bosch boilers
InsuredWith full public liability insurance
Family-run since 2006Built on word-of-mouth recommendations
Cards acceptedCard payments subject to a 1.75% fee

What we do

Gas, heating and plumbing for homeowners, landlords, letting agents and small businesses

As a family-run business, we specialise in gas boiler installation, boiler servicing, heating repairs, plumbing, and power flushing across Bedfordshire, Hertfordshire, and Buckinghamshire. We serve homeowners, landlords, letting agents, and small businesses.

New boiler installation

We are an accredited installer for top boiler manufacturers. This means we can offer a guarantee at no extra cost, saving you money. We are offering up to 12 year parts and labour guarantee on selected Worcester Bosch boilers.

Boilers that are over ten years old waste a lot of valuable energy. All replacement or new gas-fired boilers must be a condensing boiler. Older boilers convert as little as 60% of the fuel they use into heat, which has a big impact on your home heating bills and the environment. Modern condensing boilers improve efficiency to over 90%.

We specialise in condensing boilers from many manufacturers including Worcester Bosch and Vaillant. We can carry out a free quotation to assess which boiler suits your needs from combination boilers, system boilers and heat only boilers.

Combination boilersSystem boilersHeat only boilersWorcester BoschVaillant

Give us a call on 07775 881505 for a free quote

A new white boiler with a blue display, fitted on a wall above tidy pipework

Testing an open boiler with a flue gas analyser during a service

Boiler servicing

Every service starts with a general inspection of the overall condition of the boiler, including asking you about its performance and service history. We then clean and/or adjust the parts that matter.

Our boiler service includesService record

Flue and flue terminal
Combustion Fan (where fitted)
Pilot Burner
Main Burner
Main Heat Exchanger (condensing boilers)
Condense Trap & Drain (condensing boilers)
Gaskets & Seals
Gas Safety And Carbon Monoxide Test

We issue a Boiler Service Certificate and will send you a yearly reminder to advise that the next service is due.

The black Three Counties Gas & Plumbing van in full livery

Central heating & boiler repair

Due to our wealth of experience in this industry we have come across all different types of fault on boilers and heating systems, so why not give us a call.

No matter what type of boiler you have we can quickly diagnose and repair it using quality components and parts. We carry many parts on our van which we find are the most frequent causes of faults, which can get your heating and hot water up and working the same day.

All makes of gas boilers serviced and repaired.

Landlord gas safety inspection & certificates

In 1996 the government passed a law that requires all landlords, who rent either part or all of a property, to have all household gas appliances and pipes checked every 12 months with a Landlord gas safety certificate to this effect.

What does a Landlord Gas Safety Inspection include?

Check appliance for gas tightness
Check standing and working pressures if test points are available
Check burner pressure/gas rate against manufacturers guidelines
Check for satisfactory provision of all necessary ventilation
Test flue flow to ensure removal of products of combustion
Check satisfactory operation of all the flame failure devices
Check for physical stability, presence and effectiveness of stability brackets (where appropriate)
Investigate any evidence of unsafe operation and report to the person responsible

Landlord gas safety check

from £60+VAT

We can also service the boiler at the same time for an extra £20 + VAT.

Book your gas safety check

Power flushing

Does your system suffer from any of the following?

Dirty black or brown water present when bleeding radiators
Radiators slow to heat up due to blockage
Radiators cold all over due to blocked valves and pipes
Radiators cold at bottom due to black sludge build up
Irritating boiler noise from sludge or lime scale build up, a warning sign of imminent costly problems
Little or no hot water due to blocked pipes and heat exchangers
Boiler cutting out and no circulation due to blocked pump
Radiators cold at top and need bleeding due to gases, a by product of rusting
Having to bleed radiators regularly
Pin holed leaking radiators

Two magnetic filter rods caked in black sludge pulled out of a heating system during a power flush — Sludge caught on the magnetic filters during one of our power flushes.

The solution

We can carry out a powerflush without any mess or major upheaval with our Kamco power flush machine, which connects to your system either by removing the heating pump or a radiator, so we can flush the whole system without removing additional radiators. Two strong magnetic filters fitted inline with the machine catch and trap the sludge, removing the iron oxide from your system.

Our Kamco power flush machine works on high flow rates and not high pressure which greatly reduces the risk of leaks.

Once the sludge is out we flush with clean water until each radiator runs clear and the PH levels are correct, then we neutralise and inhibit your system.

We have successfully completed Kamco’s training course. All boiler manufacturers now advise that heating systems should be flushed on new boiler installations, or the boiler warranty can be invalidated.

MagnaClean & magnetic filters

It is advisable to fit these filters on all heating systems to prevent sludge and debris entering the heating components, such as pumps, radiators and boiler heat exchangers. Without a filter, the life of those components can be shortened.

Modern central heating systems with high efficiency boilers are clean, efficient and economical, but only if operating at peak performance. The natural build-up of black iron oxide soon impairs performance and eventually clogs the boiler and radiators. A MagnaClean Professional filter traps that sludge, cutting heating energy bills by up to 6% per year.

These filters really can prolong the life of your heating system.

Unvented Megaflo systems

Megaflo and unvented hot water systems give you equally high pressure in every room of your home, whether you live in a studio flat or a house with multiple bathrooms.

An unvented hot water cylinder we installed with new copper pipework

No noisy unhygienic tank in your loft (a must for loft conversions)
No noisy expensive shower pumps
Great pressure at your taps and showers
Quicker and more energy efficient at heating water and retaining water temperature
25 Year Guarantee

21°

Smart thermostats

We are a Nest Pro installer and have fitted many of these smart learning thermostats. We also fit Hive Active thermostats. Call us for a quotation.

Plumbing

We have learnt that no matter how small a job is, it’s important to get it right first time. We are experienced in all types of domestic plumbing and provide our clients with a service that is second to none.

Leaks
Overflows
Burst / frozen pipes
Replacement ball valves
Hot water problems
Immersion heaters
Hot Water Cylinders
Thermostatic radiator valves

Corroded old pipes found under the floorboards on a repair job — Old pipework under the floor, found on a leak repair.

On the job

Boilers opened up, cylinders plumbed in and systems left working

We pride ourselves on exceptional service, ensuring your property is left clean and tidy after every job.

A boiler with its front cover off, showing the heat exchanger and internals

The burner and fan assembly taken out of a boiler during a service

A white boiler installed in an outbuilding with new pipework

A wall-hung boiler beside an unvented cylinder in a utility room

About us

Founded in 2006 by Andrew Sweedy

Andrew SweedyDirector, with Abigail Sweedy, of Three Counties Gas & Plumbing Ltd

Three Counties Gas & Plumbing Ltd is a trusted, family-run business delivering plumbing and heating services in Leighton Buzzard, Bedfordshire, Hertfordshire, and Buckinghamshire. Andrew began his career with British Gas in 1999, completing a rigorous apprenticeship and advancing to a senior technician role. As a leader, he managed a team of 15 engineers, handled complex technical jobs, and provided specialised training.

With over 25 years of industry experience, Andrew established Three Counties Gas & Plumbing Ltd to bring his passion for quality workmanship directly to customers. Since 2006, our Gas Safe registered team has built a strong reputation for reliability and professionalism, earning countless word-of-mouth recommendations.

Whether you need boiler installation, emergency repairs, or plumbing services, we work with transparent pricing and a customer-first approach. Contact us today for a free, no-obligation quote.

1999Starts with British GasA rigorous apprenticeship, then a senior technician role.
Before 2006Leading a teamManaging a team of 15 engineers and providing specialised training.
2006Three Counties foundedAndrew sets up on his own to work directly for customers.
2011A limited companyThree Counties Gas and Plumbing Limited is incorporated.

An earlier Three Counties Gas & Plumbing van in silver livery

Gas Safe registered business 228490

We are a Gas Safe registered business. Gas Safe Register is the official gas safety organisation in Great Britain, responsible for the registration and regulation of gas engineers. Our engineers are trained by British Gas and hold City & Guilds qualifications, and we carry full public liability insurance.

Reviews

What our customers say

4.6from 32 Google reviews

“Our Aqualisa shower packed up due to a faulty issue with our processor, Andrew arranged the part and installed within a week, service was spot on and our shower has never worked so well since being here!”

Liam Murphy · Google review, 2026

“Clean, tidy and speedy repair for programming unit. Andrew was helpful with my queries about the problem and arranged a visit at a time that worked for me. Would use again - recommended.”

Matthew Clark · Google review, 2025

“Superb service from Andrew, I have used Three counties a few times and every time the job has been great and reasonably priced, highly recommended .”

Adrian Kirk · Google review, 2026

“Andrew was the third gas engineer we had tried after to moving to Leighton buzzard and we have used him ever since. Fair prices, great workmanship, very responsive and a pleasure to deal with.”

Tom Ratcliffe · Google review, 2021

“I’m not sure how I first came across Three Counties Gas & Plumbing when I moved to Leighton Buzzard seven years ago, but I’m very glad I did!
Andrew is extremely experienced and he’s also a genuinely nice guy to deal with. He’s calm, professional, and just gets things sorted.
He’s very honest and will never recommend work that you don’t actually need. And for the quality of work he delivers, he offers excellent value for money.
I wouldn’t hesitate to recommend Three Counties Gas and Plumbing.”

Annette Angell · Google review, 2026

Where we work

1Bedfordshire
2Hertfordshire
3Buckinghamshire

Plumbing and heating services in Leighton Buzzard and surrounding areas, including Dunstable, Aylesbury and Milton Keynes.

Opening hours

Monday - Friday: 07:00 - 18:00
Saturday: 08:00 - 17:00
Sunday: 08:00 - 13:00

Flexible scheduling, including evenings and weekends.

Contact

Call us today for a free quote

Alternatively fill in the form and we’ll get back to you as quickly as possible.

Directors: Andrew Sweedy & Abigail Sweedy. Three Counties Gas & Plumbing Ltd, Stewkley, Leighton Buzzard.