Domestic Boiler Installation
New Boiler Installation and Replacement in London
We provide new domestic natural gas boiler installation and replacement for homes across London, with the work assessed for your property. Smell gas: leave and call the National Gas Emergency Service on 0800 111 999. For suspected carbon monoxide symptoms, get fresh air and call NHS 111, or 999 if serious, before arranging boiler work.
Request an installation quote on 020 3740 6785, our 24/7 phone line. Our Gas Safe registered engineers can assess the existing boiler and proposed replacement.
Call with your postcode, the boiler make and any fault code showing.
- Gas Safe registered: 648977
- Phone line open 24/7
- Same-day appointments available
When Is Gas Boiler Replacement the Right Next Step?
Gas boiler replacement should follow an assessment of safety, repair options, parts availability and the history of failures.
- Repeated breakdowns warrant checking whether faults share an underlying cause.
- Unavailable parts can limit repair options.
- Repair cost needs weighing against the boiler’s condition and history.
Age, pressure loss, noise or a fault code alone cannot establish that replacement is necessary.
If gas is escaping, avoid flames and electrical switches. Ventilate and turn off the gas only if safe, without delaying leaving. Call 0800 111 999 from a safe place. Treat a sounding carbon monoxide alarm as real: carbon monoxide has no smell. For suspected exposure, get fresh air and medical help first, then contact the gas emergency service.
Where a repair remains viable, explore gas boiler repair. For a fuller decision checklist, read Should I repair or replace my boiler?.
What the Installation of a New Boiler Should Include
A new boiler installation should cover the appliance, suitable connections, system preparation, commissioning and handover records. Use these six checks to compare the proposed work and its deliverables:
System Cleaning, Inhibitor and Magnetic Filtration
The existing system’s condition helps determine the cleaning, inhibitor treatment and filtration needed. A magnetic filter captures magnetic heating debris; inhibitor helps control corrosion. Neither is a universal remedy for poor heating or domestic-water limescale.
Check that the scope identifies:
- The assessed water condition and recorded checks.
- Cleaning and treatment appropriate to the manufacturer’s requirements.
- Whether filtration is needed and how it will be maintained.
A powerflush should follow assessment, rather than being assumed for every installation.
Heating Controls Matched to the New Boiler
Heating controls need to suit the new boiler and the way your heating is arranged. The quote should identify whether the thermostat, programmer and room controls will be retained or replaced. Smart controls are an option where compatible.
For separately required work,.
Heating controls and thermostat fitting
- Property demand and boiler selection: Assess heating and hot-water needs. The specification should identify the proposed boiler and why it suits the home.
- Location, flue and condensate: Assess access, the flue route and condensate drainage. The scope should describe any changes needed.
- Gas supply and heating compatibility: Check the existing supply and heating connections. Required alterations should be identified before fitting.
- Water preparation and controls: Specify cleaning, treatment and control compatibility. Clarify which components stay and which change.
- Commissioning and demonstration: The engineer completes the applicable safety and operating checks. You should receive an explanation of the user controls.
- Records and notification: Clarify the commissioning record, applicable Building Regulations notification, instructions and manufacturer documentation you should receive.
Ask whether removal, disposal, access equipment and making good are included. These should be explicit in the quote, alongside any additions that depend on the survey.
From Boiler Survey to Commissioning and Handover
Installation progresses from assessing the property and agreeing the work to fitting, commissioning and explaining the finished system.
Discuss your home
Provide your postcode, existing boiler details, heating needs and reason for considering replacement.
Assess and specify
The survey checks relevant services and installation constraints. Agree the appliance, included work and exclusions before booking.
Plan the installation
Confirm the appointment, expected work duration, access arrangements and likely heating or hot-water interruption.
Commission and hand over
The engineer completes the required gas and operating checks, demonstrates the controls and completes the relevant records.
Appointment availability and fitting duration are separate. Never open the boiler casing or attempt gas work yourself.
Combination Boiler Installation or a Replacement System or Regular Boiler?
The suitable boiler type depends on heating demand, hot-water use, available space and the existing system.
Combi
Provides hot water on demand; suitability depends partly on the mains supply and simultaneous usage.
System
Works with a compatible stored-hot-water arrangement.
Regular
Uses a separate hot-water store and associated existing system components.
A survey should consider heat loss, radiators, water demand and installation constraints. Bedroom count alone is insufficient for selecting output. Existing storage arrangements need assessing for compatibility; their presence does not mean cylinder work is included.
Explore Which suits my home: a combi, system or regular boiler?.
What affects the cost
What Changes a New Boiler Installation Quote?
A new boiler installation quote depends on the appliance selected and the work needed to fit it safely into your home.
The main factors are:
- Boiler specification and compatibility.
- Keeping or changing its location.
- Flue and condensate arrangements.
- Gas-pipe alterations.
- System condition, preparation and controls.
- Access equipment and associated building work.
Compare included work and exclusions, including disposal and making good. Ask how additional work would be agreed if an issue emerges.
If you want new radiators as well, ask for that work to be specified separately. Replacing the boiler does not automatically require replacing every radiator. Call 020 3740 6785 for a price for your job.
Typical London prices
- Like-for-like combi, supplied and fitted: £1,650-£3,000 + VAT
- System or regular boiler, or a combi conversion: £2,350-£4,150 + VAT
Typical London price range, plus VAT at 20%. Your price depends on the boiler, the fault, the parts and when the work is done; ask on the call.
Boiler Installation Across London: Check Your Postcode and Property
For installation in London, provide your postcode and confirm whether the property has its own domestic gas boiler. Check the areas we cover in London and tell us:
- Whether the home has an individual boiler or communal heating.
- Which floor it is on and any access restrictions.
- Whether you want to change the boiler’s location.
A communal-heating flat may have a heat interface unit rather than a gas boiler. Confirming the arrangement helps establish whether this service fits your enquiry.
Evidence to Check Before Choosing a Boiler Installer
Check the installer’s Gas Safe registration, the attending engineer’s relevant qualifications and the written installation scope.
All Service 4 U has Gas Safe business registration 648977. Before work begins:
- Check the business identity and the engineer’s current Gas Safe ID.
- Confirm the engineer’s listed work categories cover the proposed gas work.
- Check that the specification explains commissioning, handover documents and notification responsibilities.
Keep the agreed scope with your installation records so you can refer back to what was specified.
Boiler repair, servicing and gas work
Request a New Boiler Installation Quote in London
Call 020 3740 6785 to discuss a new boiler installation quote for your London home with our Gas Safe registered engineers. Call us 24 hours a day, 7 days a week.
Have your postcode, current boiler model if known, reason for replacement and preferred location ready. Scope and timing need confirmation. You can also contact us about boiler installation. Use only externally visible details; leave the casing closed.
020 3740 6785
Frequently Asked Questions
How Long Does It Take to Fit a New Boiler?
Fitting time depends on the agreed work, access and whether the boiler’s location or system connections change. Flue work, pipe alterations, system preparation and commissioning all affect the schedule. The wait for an appointment is separate from time spent fitting. Before booking, ask for the expected duration and likely interruption to heating and hot water.
What Certificate Should I Receive After Boiler Installation?
For a notified gas boiler installation in England, the Building Regulations Compliance Certificate is separate from the appliance’s Benchmark commissioning record. Confirm who will notify the work through Gas Safe Register and follow up missing documents. Your records should include:
- The completed commissioning checklist and user instructions at handover.
- Applicable manufacturer registration confirmation.
- The compliance certificate following notification.
Keep these documents together for future servicing and reference.
Can I Book a Next-Day Boiler Installation?
Next-day installation needs confirmation after the property, required work, equipment availability and appointment schedule have been checked. Call our 24/7 phone line to discuss your preferred date. Same-day appointments are available, but an appointment does not promise a completed installation that day. Necessary assessment, preparation and commissioning still need to be allowed for.
Can I Ask for a Vaillant, Worcester Bosch or Baxi Boiler?
Yes, you can state a preferred brand when enquiring; model availability and suitability need confirmation. Mention your existing boiler model and what you want the replacement to improve. Heating demand, hot-water use, available space and system compatibility still need assessing. A brand preference alone does not establish which boiler will suit your home.
Does an Unsafe Boiler Always Have to Be Replaced?
No. An unsafe boiler must not be used, but that finding alone does not establish that replacement is the only remedy. Follow the engineer’s warning notice and ask for an explanation of the defect and remedial options. Never reconnect or restart an isolated appliance. If gas or carbon monoxide is suspected, follow the emergency advice above before discussing repair or replacement.
Will Missing a Service Affect My New Boiler’s Manufacturer Warranty?
Missing a required service can put a manufacturer’s warranty at risk; the exact conditions depend on the boiler and its terms. Keep commissioning and service records, and check the applicable servicing schedule and registration requirements. Ask about these at handover so you know what to arrange. Manufacturer warranty conditions are separate from any terms concerning the installer’s work.
Still have a question or need urgent assistance? Call 020 3740 6785, tell us what has happened and we will tell you what happens next.