Central Heating London — Repair, Install & Service
No heat, no hot water, cold radiators or a leaking system? Gas Safe registered engineers across all 32 London boroughs. Diagnosis from £95, pump replacement from £180, new boilers from £2,200. Compliant with BS 7593, BS EN 12828 and Building Regs Part L.
Same-day attendance 24/7. Fixed price confirmed before any work starts. 12-month parts and labour guarantee.
Central heating repair in London costs £95–£140 for a diagnostic visit, £180–£320 for a circulator pump replacement, £160–£260 for a motorised valve, and £130–£210 for a thermostat. A full BS 7593 power flush is £450–£850. A new condensing boiler installed to Building Regs Part L starts at £2,200. Call 0207 046 1363 for a same-day fixed-price quote.
Central Heating Cost London — 2026 Fixed Prices
Every job is a fixed price agreed on the call or after a 60-minute on-site diagnostic. No day-rate billing, no parking fees in the Congestion Zone, no out-of-hours premium on pre-booked work. All prices include VAT and a 12-month parts and labour guarantee.
| Job | Typical Cost | Time On Site |
|---|---|---|
| Diagnostic call-out — 60 min on-site | £95–£140 | 1 hour |
| Circulator pump replacement (Grundfos / Wilo) | £180–£320 | 1.5–2.5 hours |
| Motorised zone valve (2-port or mid-position) | £160–£260 | 1.5–2 hours |
| Room thermostat / programmer replacement | £130–£210 | 1 hour |
| Expansion vessel re-charge or replacement | £140–£280 | 1–2 hours |
| TRV head + body replacement (per radiator) | £75–£140 | 30–45 min |
| Full chemical / power flush (BS 7593) | £450–£850 | 6–8 hours |
| New combi or system boiler (supply + install) | from £2,200 | 1–2 days |
* Prices include VAT and 12-month guarantee. Fixed quote confirmed before any work begins.
What we do
Every Central Heating Job, Under One Roof
From a £95 diagnostic on a stone-cold radiator to a £6,000 full new system in a Victorian terrace, the same engineers do all of it — no subcontracting, no handoffs.
Central Heating Repair
Fast diagnosis and repair of all central heating faults — no heat, low pressure, kettling, pump failure, valve faults and frozen condensate.
New System Installation
Full sealed-system design and install to BS EN 12828, including condensing boiler, TRVs, smart controls, magnetic filter and inhibitor dose.
System Upgrade
Upgrade gravity-fed and open-vented systems to modern pressurised sealed systems with weather-compensated boiler controls.
Annual Servicing
Manufacturer-spec service — combustion analysis, pump test, expansion vessel re-charge, F1 inhibitor check, magnetic filter clean.
Pump Replacement
Grundfos and Wilo circulator pumps replaced same day. Bronze-bodied open-vent pumps and high-efficiency A-rated sealed-system pumps in van stock.
Motorised Valve Replacement
Honeywell V4073, Drayton ZA6 and Sunvic two-port and three-port mid-position valves swapped without draining the whole system.
Thermostat & Controls
Mechanical, digital, programmable and smart thermostats — Nest, Hive, Tado, Drayton Wiser — installed and commissioned.
Power Flush & Chemical Clean
Magnacleanse and dynamic power flush to BS 7593 to clear magnetite sludge, restore flow and protect new boilers.
Annual service
What We Check On Every Visit
An annual service is not just a quick look at the boiler. The whole system gets a structured workover so that next winter the heat is there when you need it. Here is what is included on every standard service across London:
- Combustion analysis on the boiler with calibrated FGA — CO/CO2 ratio recorded to manufacturer tolerance
- System pressure check with the boiler hot and cold — diagnosing expansion vessel and PRV faults
- Pump head measurement — confirming the circulator is delivering rated flow against system resistance
- Magnetic filter inspection and clean — magnetite mass recorded, F1 inhibitor concentration tested
- TRV and lockshield balance — flow and return delta-T measured across every radiator
- Motorised valve operation test — confirming mid-position synchronisation and end-switch contact
- Programmer and thermostat schedule audit — checking for clashing time zones and orphaned schedules
- Frost protection check — boiler frost stat, condensate trap trace heating and pipe lagging
How it works
From Call To Heat — 5 Steps
Call or WhatsApp
Describe the symptom. We confirm a fixed call-out fee and an arrival window, normally same-day across London.
Engineer attends
Gas Safe engineer arrives with a fully stocked van — pumps, valves, PRVs, thermostats, fittings.
Diagnose on site
Pressure, flow, combustion and electrical tests isolate the actual fault — no guess-and-swap.
Fixed quote + fix
You see the price before the spanner moves. 80% of faults are sorted from van stock on the same visit.
Test and sign off
Full system test, BS 7593 inhibitor check, paperwork emailed within 24 hr. 12-month guarantee starts.
Technical compliance
Standards We Work To
Central heating in 2026 is a regulated trade. The codes below are the ones our engineers work to on every install, repair and service — not as a marketing line, but because non-compliant work voids manufacturer warranties, invalidates landlord insurance and gets flagged by Building Control on resale.
Code of practice for the preparation, commissioning and maintenance of domestic central heating and cooling water systems
Sets the requirement for chemical cleaning of the system before a new boiler is fitted, the dose rate of corrosion inhibitor (typically Sentinel X100 or Fernox F1 at 1% by volume) and an annual inhibitor concentration check. A new boiler installed onto an uncleaned system breaches BS 7593 and voids most manufacturer warranties.
Heating systems in buildings — Design for water-based heating systems
Governs the design of sealed central heating systems — pipe sizing, pump head selection, expansion vessel sizing, pressure relief settings and circulation arrangements. Every new install we design uses the procedure in this standard so the system is sized for the actual heat loss of the property, not a rule of thumb.
Approved Document L — heating system efficiency and controls
Requires every new wet central heating system to include weather compensation or load compensation, time and temperature zone control, an automatic bypass and TRVs on all radiators outside the room with the room thermostat. The 2022 update raised the minimum boiler seasonal efficiency (ErP) to 92% and made flow temperature commissioning to 55 °C the default for new installs.
Statutory duties for gas appliances
Every gas-fired boiler we touch is worked on by a Gas Safe registered engineer. New installs and any work on the gas carcass are notified via the Gas Safe Building Regs Compliance scheme, producing the certificate the conveyancer asks for on resale.
Real London jobs
Recent Cases — What It Actually Costs
Real worked examples from the last quarter. Property type, fault, fix and final invoice — so you can pre-judge roughly what to expect when the engineer rings the bell.
Victorian terraced, 3-bed, Islington — no heat in deep cold snap
Customer reported no heat, boiler running normally. Diagnostic at £110 found a seized Grundfos UPS 15-50 pump — humming, no flow. Replaced with a new Grundfos UPS2 15-50/60 A-rated pump. Bled the system, re-pressurised to 1.2 bar, dosed Sentinel X100 inhibitor. Total invoice £265, on site 2 hours, heat back same evening.
Edwardian semi, 4-bed, Camden — cold radiators downstairs only
Upstairs radiators piping hot, downstairs lukewarm. Found the lower zone motorised mid-position valve (Honeywell V4073) failed to swing — actuator burnt out. Replaced the valve actuator (head only, no system drain) and re-checked balance. £210 fitted, 90 minutes on site.
1930s semi, Wandsworth — cold-bottom radiators across the house
Classic magnetite sludge. Boiler 11 years old, never flushed. Dynamic power flush across 9 radiators over 7 hours to BS 7593, plus Magnaclean Pro2 filter fitted on the return. Flow temperatures restored, kettling gone. £620 total. Boiler now scheduled for replacement next spring with the cleaned system protected from day one.
New-build 2-bed flat, Greenwich — repeated pressure drops
Sealed system losing 0.5 bar every week. No visible leak. Expansion vessel pre-charge tested at 0.2 bar (should be 1.0 bar) — vessel waterlogged. Re-charged, system pressure stable for the test week. Booked back four months later — vessel had failed properly. Replaced with a 12-litre Zilmet vessel for £230. Pressure rock-solid since.
Period conversion flat, Kensington — boiler kettling and banging
Worcester Greenstar 30CDi making distinctive boiling-kettle noise on the hot water cycle. Heat exchanger scaled and partially sludged. Power flush to BS 7593, descaler dosed on the primary circuit, Sentinel X400 cleaner soaked for 30 minutes, full rinse and re-fill with X100 inhibitor. Kettling eliminated, boiler runs silent. £780 across the day.
Terraced HMO, 5-bed, Hackney — combined CP12 + heating service
Landlord on PPM contract booked the annual gas safety certificate (CP12) and combined heating service. Combustion analysis on the Vaillant ecoTEC plus 832 within tolerance, expansion vessel re-charged from 0.6 bar to 1.0 bar, Magnaclean cleaned (15g magnetite captured), F1 inhibitor topped to 1.2%. CP12 and service certificate issued same visit. £180 bundled.
Why ERL
Why London Homes Call Us First
Gas Safe + manufacturer trained
Every engineer carries Gas Safe ID and manufacturer accreditation for Worcester Bosch, Vaillant, Ideal, Baxi and Viessmann.
Van stock = same-day fix
Pumps, valves, thermostats, PRVs, expansion vessels and 25mm copper in the van. 80% first-visit fix rate.
Fixed prices, no day rates
Quote agreed before any work. No surprise extras at the end of the job.
BS 7593 chemical care
Every visit includes an inhibitor concentration check. New boilers always preceded by a flush — never on a dirty system.
12-month parts + labour guarantee
On every job — repair, service or install. New boilers carry the manufacturer warranty on top (typically 7–10 years).
Building Regs notification
Every notifiable install is logged via the Gas Safe scheme. Building Regs Compliance Certificate within 28 days.
FAQ
Central Heating Questions Londoners Ask
Fifteen of the questions we get on the phone every week. If yours is not here, call 0207 046 1363 — most diagnostics start on the call before the engineer even leaves the depot.
Why is my central heating not working at all?
Why are my radiators cold only at the top?
Why are my radiators cold only at the bottom?
Why does my boiler fire up but produce no heat in the radiators?
What are the signs of a failing central heating pump?
How much does it cost to replace a central heating pump in London?
How much does a full central heating system cost to install in London?
How long does a new central heating install take?
Why is my central heating making banging or knocking noises?
Why does my central heating keep losing pressure?
What is a power flush and when is it needed?
Do you fit smart heating controls?
Do you work on conventional, system and combi boilers?
Is my central heating covered by Building Regulations?
How often should I have my central heating serviced?
Areas covered
Central Heating Engineers Across All 32 London Boroughs
Same-day attendance across Zones 1–6, including the City of London. Heaviest demand from Camden, Islington, Hackney, Lambeth and Wandsworth, where Victorian and Edwardian housing stock means older systems that benefit most from a BS 7593 clean and a controls upgrade.
Service area
Service Area — All London Boroughs
Engineers are based across North, South, East and West London for fast response. Average attendance is 60–90 minutes from call in Zones 1–3, 90 minutes to 2.5 hours in Zones 4–6. Out-of-hours and Sundays included at no premium for emergency no-heat callouts.
Related ERL services
One Trade, Or All Of Them
Central heating sits next to gas, electrical and plumbing — most London call-outs touch two of them. We bundle visits so you do not pay multiple call-out fees for one problem.
Heat Back On Today
Gas Safe engineers across all 32 London boroughs. Fixed-price diagnosis from £95. 12-month guarantee on every job. Compliant with BS 7593, BS EN 12828 and Building Regs Part L.
London 247 Home Services Ltd · Co. No. 17120057 · Gas Safe registered · £5M public liability insurance