Emergency boiler repair: checks, costs and what to do
No heating or hot water is miserable, especially in winter. A few safe checks can fix some faults in minutes. If they do not, you need a Gas Safe registered engineer, and you can send us your job to compare quotes.
Smell gas or feel unwell? Act first
If you smell gas, leave the house and call the National Gas Emergency Service on 0800 111 999. Do not switch anything on or off. Headaches, dizziness or nausea can also mean carbon monoxide, so get outside into fresh air and call 999 if anyone feels very unwell.
Safe checks before you call
Some faults have simple causes, so a few minutes of checking can save a call-out fee. Never remove the boiler casing, because only a Gas Safe engineer may work on the gas side.
Check the pressure
Many boilers work best at about 1 to 2 bar when cold. If the gauge has dropped near zero, your manual may show how to top it up with the filling loop. A pressure that keeps falling points to a leak, which needs an engineer.
Check the power, gas and thermostat
Make sure the boiler has power and that the thermostat is calling for heat. Check that your gas meter has credit if it is a prepayment meter. Then look at the display for a fault code.
Note the fault code
Write down the make, model and any code on the display. An engineer can often tell what part is needed from the code, which saves time on the visit.
What does a boiler repair cost?
Price guides from Checkatrade, Fantastic Services and Housekeep suggest most repairs cost about £150 to £400, including parts and VAT. Emergency repairs run higher, with Checkatrade quoting about £225 to £675. London and the South East usually cost more.
Gas Safe engineers often charge about £50 to £80 an hour, and many include the first hour in the call-out fee. Ask what the fee covers, because parts are usually extra. Our new boiler cost guide helps you decide between repairing and replacing.
Repair or replace?
An old boiler can cost more to mend than it is worth. As a rough rule, think about replacing it when the boiler is over ten to twelve years old and the repair costs a large share of a new one. Ask the engineer for both prices in writing, since you can then decide calmly.
Our guide on when to replace a boiler explains the signs. Grants rarely cover a like-for-like gas boiler, as our boiler grants guide shows.
How to choose an engineer
Only a Gas Safe registered engineer may legally work on a gas boiler. Ask to see the ID card and check the number on the Gas Safe Register. We do not vet or guarantee the engineers who respond, so the check is yours to make. Our guide to finding a tradesman you can trust lists the other checks.
Frequently asked questions
How much does an emergency boiler repair cost?
Guides we checked suggest about £225 to £675 for an emergency repair. A normal repair often costs £150 to £400. Prices rise out of hours and in London.
My boiler has broken down. What should I do first?
Check for gas or carbon monoxide signs, then check the pressure, power and thermostat. Note the fault code, and call a Gas Safe engineer if the boiler still will not work.
Should I repair or replace my boiler?
It depends on age and repair cost. Boilers over about twelve years old are often better replaced when the repair is large. Ask for both quotes.
Do I need a Gas Safe engineer?
Yes. By law, anyone who works on gas appliances must be on the Gas Safe Register.