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Cost of Repairing a Boiler

A guide on what to expect when your boiler needs repairing, including the costs for labour and materials.

1-6 Hours
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This article will detail how to repair certain parts of a boiler system. Boiler systems are complex designs, and most parts should only be investigated and repaired by a qualified professional CORGI-registered engineer. There are some areas that can be investigated before such an engineer is called, but any invasive work must be carried out by an accredited professional.

Costs involved with repairing a boiler

Below is a table of different types of repairs and their average costs (this includes the materials and the labour):

Repair Type Avg. Repair Cost
Minor repairs £50-£150
Medium repairs £150-£300
Major repairs £300-£450

Costs can vary depending on what type of trader you use (sole trader, small business or national company) - plumbers on average charge around £60 per hour for labour.

What repairing a boiler entails

Boilers are complex systems that mix gas and electrical elements to heat water for a house or office. Boilers generally come in three basic types:

  • A ‘combi’ (combination) boiler is both a high-efficiency water heater and central heating system in an individual compact unit. Combi boilers heat up water directly from the mains and activate when you turn on a tap, which means that you don’t need either a hot water storage cylinder or a cold-water storage tank in the roof space.
  • System boilers need a cylinder for hot water storage; however, the main heating and hot water system are built into the actual boiler, making it faster and easier to install. There’s no need for a tank to take up space in the loft, so these are a good choice in a home with small or no loft space.
  • Regular boilers are preferably suited to properties that already have a traditional heating and hot water system that’s connected to a separate hot water cylinder. These boilers need a cold-water storage tank in the loft to supply the hot water chamber along with a tank that upholds the water level of the central heating system to prevent it running dry.

The central part of all of these systems is the actual boiler, which is a closed system that only requires periodic maintenance. If the boiler fails, you can be left without hot water in the home, so fixing them becomes important.

Fixing a boiler will entail removal of panels, inspection and test of different elements using a range of specialist equipment including gas detectors and multimeters to establish parts that are failing. The technical aspect of the equipment usually means that they must be carried out by trained and competent personnel.

Other jobs to tackle

Fixing a boiler doesn’t usually allow for other tasks to be completed, though it may be an opportunity to carry out routine service on the boiler and check the condition of water tanks and connecting pipes. Checking the condition of your boiler is also an excellent time to clean it throughout.

General advice when getting a boiler repaired

Unless you are a qualified CORGI fitter, there is little that you can do yourself. There are some areas that can be tackled by the homeowner, including:

Re-pressurise your boiler

There’s usually a water pressure indicator on the front of your boiler, and might be behind a removable panel. If the indicator is below one bar, your boiler pressure is too low. You need to locate the boiler’s filling loop that’s generally at the bottom of the unit. Ensure the boiler is turned off and the ends of the hose are attached to the valves, then open the valves, and you should be able to hear water filling up the system. Observe the pressure indicator until it moves to 1.5, then close the valves and turn the boiler back on. If the pressure is too high, you should contact a boiler expert.

Reset your boiler

Refer to the boiler’s manual to locate the reset button. Once found, push it for ten seconds. After a few minutes, the boiler should cycle and begin working again. Try it a second time if the primary reset doesn’t work. If it still fails to restart, you will need to call a boiler expert.

Some apparent boiler problems may not be to do with the boiler at all. If you have boiler issues, try the next two remedies too.

Bleed your radiators

If the heating has been on, check the radiators to find out which ones aren’t warm and not working. Once they’ve been recognised, turn off the central heating. Once it’s cool, use a radiator key and connect it to the valve in the suitable place at the top. With a cloth in place over the key and valve, gradually turn the key anti-clockwise. If you can hear a hissing noise, it means that there’s gas escaping. When all of the gas has escaped, the valve needs to be closed once more. Mop up any escaped water and try the boiler again.

Replacing thermostat batteries

Take off the thermostat covering from the wall mount and turn it over to discover the battery removal slots. Remove the old batteries and change them with new ones - most thermostats will require either two double-A or two triple-A batteries. Fit the thermostat covering back onto the wall mount. Once this is done, it may take a few days for low battery warning sign to disappear from the monitor.

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Sam J

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