Nine Reasons Boilers Fail in Winter in the North East

Most people do not think about their boiler until it stops working. The problem is that the first really cold spell is exactly when you need it most - and when heating engineers are already dealing with a rush of no-heating and no-hot-water calls.

Cold weather does not magically create every fault, but it often exposes problems that were already developing. These are nine common things worth knowing about before winter demand ramps up.

1. A condensate pipe freezes

Some condensing boilers have condensate pipework that runs outside. In freezing weather that pipe can freeze and the boiler may lock out. Follow the manufacturer guidance for your appliance and see our frozen condensate pipe guide. If you are unsure, call an engineer rather than dismantling anything.

2. The heating goes from barely used to working every day

During warmer months the boiler may only be doing light hot-water work. When temperatures fall, the heating can suddenly run for hours each day. That extra demand can expose weak pumps, valves, controls or circulation problems that were much less obvious in summer.

3. Sludge and poor circulation become more obvious

If radiators heat unevenly, stay cold at the bottom or take much longer than others, there may be a circulation or system-condition issue. Black water when bleeding a radiator can also be a sign that corrosion products are present. It does not automatically mean you need a power flush, but it is worth mentioning when you book an engineer.

4. Boiler pressure keeps dropping

Repeatedly topping the pressure back up is not something to ignore. Possible causes include leaks, an expansion-vessel issue or a pressure-relief-valve problem. See our boiler pressure guide for safe homeowner checks.

5. A combi boiler struggles when you need heating and hot water together

A fault that is hard to notice in summer can become obvious once the boiler is switching frequently between heating and hot water. If you get one but not the other, or the temperature is erratic, tell the engineer exactly what happens and when.

6. Pumps or valves have been sitting relatively idle

Heating components that have seen little use over summer can show problems once the system is called on every day. A boiler service cannot guarantee that a pump or valve will never fail, but it does give an engineer the chance to inspect the appliance and pick up obvious warning signs.

7. External pipework and flues face harsher weather

Wind, rain and freezing temperatures can make existing issues around external pipework or flue terminals more obvious. From ground level only, look for anything visibly damaged or blocked. Do not dismantle or repair flue components yourself.

8. Controls are sometimes the culprit

Before assuming the boiler has failed, check the thermostat, programmer and obvious settings. Flat thermostat batteries, altered schedules and control issues can all leave you with no heating even when the boiler itself is capable of running.

9. The boiler has simply gone too long without being checked

A service is not a guarantee against future breakdowns. What it does give you is a chance to have the boiler, flue, combustion and safety checked before the busiest part of winter, rather than waiting until the house is already cold.

Do not wait for the freezing morning

If you cannot remember when the boiler was last serviced, or you have noticed pressure loss, odd noises, recurring fault codes or unreliable heating, now is the time to get some peace of mind.

Where to go next

For routine maintenance, use our boiler servicing page, with local pages for Sunderland, Durham, Washington and Houghton le Spring.

If the boiler has already stopped working, see our emergency boiler repair page or call 0191 540 2051.