Need help with a job?

By Emily Rivers
Last updated 5th June 2025

Our boilers are an appliance in the home we do not give a second thought to, until the it is not working and we are left with the boiler not heating radiators or not giving hot water! When a boiler is not firing up or turns on but with a fault, the boiler will display a fault code to signal what is wrong so that you can get the boiler fixed or serviced. 

According to warranties, reputation, trustpilot reviews, customer service… these are some of the best boilers available in the UK;

  • Alpha boiler
  • Baxi boiler
  • Glow-Worm boiler
  • Ideal boiler
  • Potterton boiler
  • Vaillant boiler
  • Viessmann boiler
  • Vokera boiler
  • Worcester Bosch boiler

These are the boiler brands we will focus on when discussing and helping identify boiler fault codes most often experienced by homeowners.

Do all boilers have the same boiler fault codes?

Most boiler manufacturers follow a simple logic like E for Error or a F for Fault. The only challenging part is that different brands of boilers have their own codes. When you get your boiler installed, be sure to hang on to the manual and keep it in a safe place. If for any reason you have lost the manual, you can always download them off the boiler manufacturers website. Worcester Bosch has a list of all of their boiler user manuals here.

Cost to fix a boiler fault code

How much will it cost to fix my boiler fault code?

Fixing a fault code can often lead to a challenging few weeks of investigation work. When you first make contact with your heating engineer, and explain to them the fault code displayed with the make and model of your boiler, they should be familiar with the boiler to know the fault that the code represents. If not, they can look it up online or in your manual and begin the diagnostics.

Some faults are easy and quick to get the boiler back up and running but may need further investigation to identify the course of the problem, e.g.; a low pressure warning (F1 on an Ideal boiler or an A04 on a Vokera boiler), once you top up the system, the boiler will reignite and the fault code should disappear but why did the system lose pressure to begin with? This could result in the discovery of a slow leak through a pinhole on a radiator or a leaking valve or a rusty heat exchanger where water is slowly dripping through.

This means the cost to fix the initial boiler fault code, may just be an hour’s call-out fee but the cost to stop the fault from reoccurring could go into the hundreds, needing more than one call-out and parts ordered, replacing faulty or leaking components.

How much labour costs to fix a boiler fault

Per

Average cost

Replacing a faulty fan

Per hour 

£80 + £230 for the fan

Replacing a burnt-out pump

Per hour 

£80 + £210 for the pump

Diagnose a blockage in circulation (F25), bleed the radiators to remove air and check water quality for signs of debris

Per hour 

£100

Repressurising the system and spending time checking for signs of leaks

Per hour 

£120

Can I reset my boiler fault code?

The boiler fault code that has been displayed will only clear after the issue has been resolved and is no longer causing stress to the boiler. After repairing or replacing the cause, your gas engineer will reset the boiler which should then clear the fault code.

What does my boiler fault code mean?

As mentioned, different brands of boilers use their own unique codes for various faults, but two of the most common error codes displayed are either an F22 or an F25 fault code.

F22 error = the boiler’s water pressure has dropped too low, and the boiler will not fire up until the pressure has been restored. This fault code is used by Glow-Worm and Vaillant boilers.

F25 error = a safety shut-off code signalling to the boiler to switch off before the system overheats as the flow temperature is increasing at 5 degrees per second while the system is not circulating quick enough due to debris or air blockage. This fault code is used by Glow-Worm and Vaillant boilers.

To make it easy for you, HaMuch as a list of some brands of boilers with a click through to find the manual you need, just click on the make of your boiler;

Here are some useful common boiler error fault codes:

E-Error Codes

The “E-error codes” are usually broken down into;

E+2 codes, e.g.; E20, often requires a gas engineer, and might involve internal sensor errors

E+3 codes, e.g.; E110, E125, E131, often a fault that you can fix as they might just need radiators bled to remove air from the system

E119 boiler error code means low water pressure, so you can top up the pressure.

E+3 codes of higher numbers, e.g.; E151 – E167, might mean a programming error and will need a heating engineer to look at the system.

EA (Worcester) or F27 (Vaillant) 

Double check your manual, but this may refer to a blocked condensate pipe that may have frozen and will need carefully defrosting.

A1 or No code (Worcester) or F75 (Vaillant) F1 (Ideal) 

Water pressure has dropped significantly low code and will require a top-up of water to boost up the pressure.

EA (Worcester) or F75 (Vaillant)

This fault usually means that the boiler’s sensor is failing to connect with the pump 

Worcester Bosch Errors

A1 Low pressure need to top up the water in the system

C1 The fan has stopped running

EA No flame is detected

260 Sensor disconnected or no water in the boiler

C6 The boiler is running too fast or running too slow

C7 Fan not running or the airflow blocked

D1 The sensor is wet or damaged

E2 Flow sensor is shorted or damaged

E5 Primary flow sensor overheated

E9 The main heat exchanger has overheated


Estimates for common heating engineer jobs;

JobEstimate
Cost to replace a hot water immersion heater£298
Cost to fit underfloor heating£1,228
Cost to service a gas fire£150
Cost to replace a vented hot water cylinder£586
Cost to replace a central heating pump£222
Cost to replace a heating programmer£255
Cost to power flush central heating systems£603 Visit
Cost to install heating oil storage tank£2,160
Cost to replace an oil boiler£3,228
New combi or system boiler installation – like for like replacement£2,718
Cost to move and relocate a boiler£830
Complete gas safety certificate for one gas appliance£90
Cost to install heated skirting boards£2,200
Cost to install an LPG boiler£2,026
Cost to install hydrogen boiler£1,350
Cost to install a gas fire£1,059
Cost to install a chimney liner£761
Cost to install biomass boiler£5,705
Cost to install a ground source heat pump£13,563
Cost to fix a boiler fault error code£85
Cost to install an unvented hot water cylinder£3,669
Cost to fit thermostatic radiator valves (TRVs)£111
Cost to fit smart heating controls£235
Cost to fit a magnetic filter for boiler£155
Cost to fit a heated towel rail£119
Cost to fit a radiator£184
Cost to install a gas cooker or hob£202
Boiler service cost£100
Boiler repair cost for pump, diverter valve or heat exchanger£233
Cheap boiler insurance£20 per month
Cost to install an air source heat pump£6,167
2. Enter postcode to get estimate
plus materials

to see who is available and get more information

Rates for other trades

Fix a boiler fault code cost in the UK
Fix a boiler fault code cost in the UK (excluding VAT or callout charges)
Location in UKFix a boiler fault code cost
Fix a boiler fault code near London£136
Fix a boiler fault code near Birmingham£98
Fix a boiler fault code near Glasgow£98
Fix a boiler fault code near Leeds£90
Fix a boiler fault code near Liverpool£100
Fix a boiler fault code near Sheffield£98
Fix a boiler fault code near Edinburgh£100
Fix a boiler fault code near Manchester£98
Fix a boiler fault code near Belfast£80
Fix a boiler fault code near Bristol£100
Fix a boiler fault code near Leicester£96
Fix a boiler fault code near Cardiff£94
Fix a boiler fault code near Coventry£102
Fix a boiler fault code near Bradford£94
Fix a boiler fault code near Nottingham£100
Fix a boiler fault code near Newcastle Upon Tyne£106
Fix a boiler fault code near Brighton and Hove£110
Fix a boiler fault code near Derby£102
Fix a boiler fault code near Hull£84
Fix a boiler fault code near Plymouth£80
Fix a boiler fault code near Stoke-on-Trent£96
Fix a boiler fault code near Southampton£106
Fix a boiler fault code near Northampton£118
Fix a boiler fault code near Wolverhampton£98
Fix a boiler fault code near Luton£128
Fix a boiler fault code near Portsmouth£108
Fix a boiler fault code near Reading£144
Fix a boiler fault code near Norwich£102
Fix a boiler fault code near Milton Keynes£120
Fix a boiler fault code near Bournemouth£104
Fix a boiler fault code near Aberdeen£92
Fix a boiler fault code near Peterborough£104
Fix a boiler fault code near Bolton£94
Fix a boiler fault code near Swindon£110
Fix a boiler fault code near Southend-on-Sea£112
Fix a boiler fault code near Warrington£102
Fix a boiler fault code near Oxford£114
Fix a boiler fault code near Swansea£94
Fix a boiler fault code near Sunderland£110
Fix a boiler fault code near Slough£136
Fix a boiler fault code near Kingswood£100
Fix a boiler fault code near Telford£98
Fix a boiler fault code near Cambridge£112
Fix a boiler fault code near Ipswich£148
Fix a boiler fault code near Blackpool£92
Fix a boiler fault code near Middlesbrough£100
Fix a boiler fault code near Dundee£96
Fix a boiler fault code near Huddersfield£88
Fix a boiler fault code near York£90
Fix a boiler fault code near Poole£108
Fix a boiler fault code near Watford£134
Fix a boiler fault code near Newport£76
Fix a boiler fault code near Colchester£124
Fix a boiler fault code near Exeter£88
Fix a boiler fault code near Blackburn£98
Fix a boiler fault code near Crawley£130
Fix a boiler fault code near Gloucester£94
Fix a boiler fault code near Stockport£98
Fix a boiler fault code near Basingstoke£136
Fix a boiler fault code near Basildon£110
Fix a boiler fault code near Cheltenham£98
Fix a boiler fault code near Gateshead£108
Fix a boiler fault code near Worthing£116
Fix a boiler fault code near Rochdale£92
Fix a boiler fault code near Oldham£94
Fix a boiler fault code near Chelmsford£114
Fix a boiler fault code near Birkenhead£100
Fix a boiler fault code near Maidstone£112
Fix a boiler fault code near Gillingham£106
Fix a boiler fault code near Salford£98
Fix a boiler fault code near Solihull£98
Fix a boiler fault code near St Helens£108
Fix a boiler fault code near Worcester£98
Fix a boiler fault code near Lincoln£104
Fix a boiler fault code near West Bromwich£98
Fix a boiler fault code near Eastbourne£100
Fix a boiler fault code near Wakefield£90
Fix a boiler fault code near Wythenshawe£98
Fix a boiler fault code near Bedford£114
Fix a boiler fault code near Hemel Hempstead£130
Fix a boiler fault code near Preston£100
Fix a boiler fault code near Stevenage£120
Fix a boiler fault code near Southport£92
Fix a boiler fault code near Bath£94
Fix a boiler fault code near Harlow£120
Fix a boiler fault code near Sutton Coldfield£98
Fix a boiler fault code near Darlington£98
Fix a boiler fault code near Chester£102
Fix a boiler fault code near Hastings£100
Fix a boiler fault code near Nuneaton£90
Fix a boiler fault code near Halifax£88
Fix a boiler fault code near Hartlepool£98
Fix a boiler fault code near Aylesbury£142
Fix a boiler fault code near Doncaster£90
Fix a boiler fault code near Grimsby£84
Fix a boiler fault code near Wallasey£98
Fix a boiler fault code near Londonderry£56
Fix a boiler fault code near Stockton-on-Tees£98
Fix a boiler fault code near Weston-super-Mare£96
Fix a boiler fault code near High Wycombe£134
Fix a boiler fault code near Ashford£114
Fix a boiler fault code near Redditch£96
Fix a boiler fault code near Wigan£98
Fix a boiler fault code near Scunthorpe£84
Fix a boiler fault code near Bury£94
Fix a boiler fault code near Paisley£100
Fix a boiler fault code near Bracknell£134
Fix a boiler fault code near Burnley£86
Fix a boiler fault code near Rugby£106
Fix a boiler fault code near Guildford£136
Fix a boiler fault code near Carlisle£80
Fix a boiler fault code near Chatham£106
Fix a boiler fault code near East Kilbride£98
Fix a boiler fault code near Newcastle-under-Lyme£94
Fix a boiler fault code near Chesterfield£90
Fix a boiler fault code near Burton upon Trent£92
Fix a boiler fault code near Tamworth£98
Fix a boiler fault code near Shrewsbury£106
Fix a boiler fault code near Woking£142
Fix a boiler fault code near St Albans£134
Fix a boiler fault code near Harrogate£90
Fix a boiler fault code near Crewe£94
Fix a boiler fault code near South Shields£96
Fix a boiler fault code near Craigavon£58
Fix a boiler fault code near Stafford£96
Fix a boiler fault code near Rotherham£96
Fix a boiler fault code near Barnsley£86
Fix a boiler fault code near Lowestoft£130
Fix a boiler fault code near Walsall£98
Fix a boiler fault code near Gosport£108
Fix a boiler fault code near Dartford£126
Fix a boiler fault code near Bognor Regis£108
Fix a boiler fault code near Corby£98
Fix a boiler fault code near Paignton£90
Fix a boiler fault code near Maidenhead£132
Fix a boiler fault code near Rochester£106
Fix a boiler fault code near Ellesmere Port£94
Fix a boiler fault code near Loughborough£96
Fix a boiler fault code near Dudley£98
Fix a boiler fault code near Bangor£80
Fix a boiler fault code near Dewsbury£88
Fix a boiler fault code near Mansfield£90
Fix a boiler fault code near Margate£104
Fix a boiler fault code near Kettering£108
Fix a boiler fault code near Cannock£94
Fix a boiler fault code near Sale£96
Fix a boiler fault code near Taunton£76
Fix a boiler fault code near Runcorn£114
Fix a boiler fault code near Farnborough£136
Fix a boiler fault code near Tynemouth£98
Fix a boiler fault code near Hereford£82
Fix a boiler fault code near Halesowen£98
Fix a boiler fault code near Widnes£104
Fix a boiler fault code near Huyton with Roby£100
Fix a boiler fault code near Scarborough£86
Fix a boiler fault code near Gravesend£116
Fix a boiler fault code near Bebington£100
Fix a boiler fault code near Kidderminster£102
Fix a boiler fault code near Stourbridge£100
Fix a boiler fault code near Barry£80
Fix a boiler fault code near Smethwick£98
Fix a boiler fault code near Dunfermline£102
Fix a boiler fault code near Livingston£108
Fix a boiler fault code near Weymouth£96
Fix a boiler fault code near Brentwood£122
Fix a boiler fault code near Barrow-in-Furness£160
Fix a boiler fault code near Hamilton£98
Fix a boiler fault code near Canterbury£108
Fix a boiler fault code near Wellingborough£112
Fix a boiler fault code near Sittingbourne£112
Fix a boiler fault code near Macclesfield£86
Fix a boiler fault code near Bootle£100
Fix a boiler fault code near Carlton£98
Fix a boiler fault code near Esher£136
Fix a boiler fault code near Clacton-on-Sea£126
Fix a boiler fault code near Lancaster£92
Fix a boiler fault code near Beeston£90
Fix a boiler fault code near Banbury£124
Fix a boiler fault code near Torquay£90
Fix a boiler fault code near Folkestone£104
Fix a boiler fault code near Kingswinford£98
Fix a boiler fault code near Bloxwich£100
Fix a boiler fault code near Bridgend£98
Fix a boiler fault code near Welwyn Garden City£132
Fix a boiler fault code near Lisburn£74
Fix a boiler fault code near Leamington Spa£112
Fix a boiler fault code near Washington£108
Fix a boiler fault code near Tunbridge Wells£130
Fix a boiler fault code near Kirkcaldy£98
Fix a boiler fault code near Hinckley£96
Fix a boiler fault code near Durham£116
Fix a boiler fault code near Cumbernauld£106
Fix a boiler fault code near Wokingham£140
Fix a boiler fault code near Horsham£130
Fix a boiler fault code near Crosby£98
Fix a boiler fault code near Yeovil£76
Fix a boiler fault code near Thundersley£114
Fix a boiler fault code near Altrincham£94
Fix a boiler fault code near Willenhall£100
Fix a boiler fault code near Christchurch£102