Gas boiler installation and replacement: combi, system and conventional boilers fitted and sized to your home by local Gas Safe registered engineers.
Our Services
Boiler Installation
About This Service
A new boiler sized to your home
T P Watts Plumbing Services fits combi, system and conventional gas boilers, sized to your home by Gas Safe registered engineers. We’re a heating engineer based in Eastleigh, serving Southampton, Portsmouth, Andover and the surrounding area, and our boiler installation in Eastleigh covers like-for-like swaps, conversions and new systems.
We fit and replace gas boilers with safety, compliance and long-term reliability as priorities. With 15+ years’ experience, we size systems for the property type, from flats and Victorian terraces to new-builds and country cottages, and install boilers from leading UK manufacturers. Every job starts with a survey and a fixed-price written quote, and ends with full commissioning, paperwork and warranty registration. You can see every town we cover on our areas page.
Our Process
How It Works
01
Site survey & recommendation
A Gas Safe engineer visits to assess property size, existing pipework, hot water needs and flue options, then recommends combi, system or conventional solutions and provides a transparent, fixed-price quote.
02
Scheduled installation
We turn up on the agreed day, remove the old boiler (safe disposal), install the new boiler, update pipework and controls, and fit flues or cylinders as required, keeping your home tidy throughout.
03
Commissioning & handover
Final safety checks, system filling and a powerflush if needed, manufacturer warranty registration and Gas Safe certificates are supplied, plus a walkthrough of controls and aftercare advice.
Benefits
What you get with T P Watts Plumbing Services
Gas Safe registered engineers
All gas work is completed by Gas Safe registered engineers for compliance, safety and to protect manufacturer warranties.
Local, experienced team
Established in Fair Oak for 15+ years, Tom and Jamie understand Hampshire homes, from flats to rural cottages, and size boilers to match real household demand.
Clear quotes & warranty support
Fixed-price proposals with a clear scope, plus help registering your boiler with the manufacturer and the safety paperwork you need.
Which boiler suits your home
We fit combi, system and conventional boilers from trusted UK manufacturers, with partner brands such as Worcester Bosch where appropriate.
Combi boiler: heats water straight from the mains when you turn on a tap, with no cylinder or loft tanks. It suits flats and homes with one bathroom, where hot water is rarely needed in two places at once. It needs good mains water pressure, and the flow drops if two showers run together.
System boiler: heats a hot water cylinder, usually in the airing cupboard, with no loft tanks. It suits homes with two or more bathrooms, where showers and taps run at the same time, as long as there's room for the cylinder.
Conventional boiler: works with a cylinder and a cold water tank in the loft. It's common in older homes and suits where that system works well, or where mains pressure is low.
We also convert traditional systems to a combi to free up the tanks and airing cupboard. Whichever type you choose, we size it from your home's size, insulation, number of radiators and hot water demand. A boiler that's too big for the home switches on and off in short bursts, called short-cycling, which wastes gas and wears it out sooner.
What affects the cost of a new boiler
Every job gets a fixed-price written quote after the survey. The main things that shape the price are:
The type of job: a like-for-like combi swap is the simplest. A system or conventional install, or a conversion to a combi, takes more work.
Cylinder work: fitting, replacing or removing a hot water cylinder.
Pipe runs and boiler position: moving the boiler to a new spot means longer pipe runs.
The flue: a new flue route, or one that needs extending, adds time.
Access: a boiler in a loft or tight cupboard can take longer to replace.
Extras: a system flush, a new cylinder, thermostatic radiator valves (TRVs) or smart controls are listed separately, so you can see each one.
What every installation includes
A survey and a fixed-price written quote
Removal and safe disposal of the old boiler
Pipework and controls updated
A flue or cylinder fitted where needed
Final safety checks and system fill
Manufacturer warranty registration
A Gas Safe certificate and commissioning paperwork
A walkthrough of your controls
Optional extras include system flushing, new cylinders, TRVs and smart controls. Our heating services page covers controls and radiator work in more detail.
FAQ
Frequently Asked Questions
It depends on the type of job (a like-for-like combi swap, a system or conventional install, or a conversion), any cylinder work, the pipe runs and boiler position, the flue and access. Extras such as a system flush or smart controls are listed separately. We survey your home first and give you a fixed-price written quote, so you know the full cost before work starts.
A like-for-like combi replacement can often be completed in a day, while system or conventional installations or conversions can take longer depending on cylinder work, pipe runs and property access. We confirm an estimated timescale at survey and include it in your written quote.
Yes. We register your new boiler with the manufacturer where required, issue the Gas Safe certificate and provide full commissioning paperwork. Most manufacturers also need a yearly service to keep the warranty valid, which our boiler servicing covers.
We carry out system conversions where suitable. That involves removing the hot water cylinder and adapting pipework, pump and controls. We explain the trade-offs at survey and provide a fixed-price quote for the complete job.
We calculate required output by assessing property size, insulation, number of radiators and household hot water demand. The aim is correct sizing to avoid short-cycling and ensure efficient, reliable heating. Details are recorded and explained in your installation report.
A repair often makes sense for a younger boiler with a one-off fault. Replacing is usually better when the boiler is well over ten years old, the same faults keep coming back, or parts for it are no longer available. If you're not sure, our boiler repairs team can diagnose the fault and tell you honestly which makes more sense.
Ready to replace your boiler?
Tell us about your home and your current boiler, and we'll arrange a survey and a fixed-price written quote from a Gas Safe registered engineer.
Other Services