Boiler stops working at night? What to do at 11pm in February

It is 11pm. The radiators are cold. The house is dropping a degree every hour. There is no hot water for a bath. You have a small kid and a meeting in the morning. Most boiler failures happen at the worst possible time, because that is when the boiler is being asked to work hardest. Here is the order to do things.

First five minutes: get the basics right

Before you ring anyone, do this in order:

1. Read the fault code. If the display shows a code, write it down. Take a photo. This is the single most useful piece of information for any engineer.

2. Check the pressure gauge. Below 0.8 bar and the boiler will not run. Top up using the filling loop underneath. If you do not know how, search "[your boiler model] filling loop" on YouTube. Most are five-second jobs.

3. Check that the gas is on. Turn on a gas hob if you have one. If the hob does not light either, the issue is the gas supply, not the boiler. Call National Grid on 0800 111 999 if you smell gas, otherwise check whether your area has been notified of a gas outage.

4. Reset the boiler. Most boilers have a reset button on the front. Hold for 3 to 5 seconds. The boiler should attempt to restart. If it locks out again immediately, do not keep resetting (more than three times can damage the boiler).

5. Check that the thermostat is calling for heat. Turn it well above room temperature. If you hear the boiler try to fire, it is responding. If nothing happens, the thermostat or wiring is the problem, not the boiler itself.

What you can safely fix yourself

A surprising amount of "broken boiler" calls turn out to be one of these:

Pressure dropped after radiator bleed

You bled radiators recently and pressure fell below 0.8 bar. Top it up to 1.2. Done. Five-minute fix.

Frozen condensate pipe (winter only)

External pipe freezes in cold weather. Pour warm tap water (not boiling) along the external section. Reset the boiler. Done.

Tripped electrics

Boiler has its own fused spur, often near the boiler. Check the fuse. If it has tripped, reset it. If it trips again immediately, call an electrician (do not keep resetting a tripping fuse).

Programmer set wrong

Power cut earlier in the day reset the timer. Boiler thinks it is the wrong time of day and is not in a heating period. Set the clock and the schedule.

Hot water temperature dial nudged

Someone bumped the dial. Boiler is set too low. Turn it up.

For everything else, you need a plumber.

When to call out at night vs wait

Genuine reasons to call a plumber at 10pm or later:

• Smell of gas (call National Grid first on 0800 111 999, then a Gas Safe registered plumber)
• Visible water leak from the boiler
• Carbon monoxide alarm sounding
• Vulnerable person (very young, very old, very ill) in the house with no other heating

Wait until morning if:

• Heating is off but house is still warm enough
• You can use electric heating, blankets, etc. for one night
• The fault code points to a non-urgent repair (most pressure or sensor faults)
• You can run hot water from another source (electric shower, kettle for washing)

Out-of-hours plumber rates in London in 2026 are typically two to three times standard rates. £180 to £350 for an after-hours callout, plus parts. It is worth checking whether you can reasonably wait until 7am.

How to get a real plumber, not a call centre

Most "24/7 emergency plumbers" advertised on Google are actually call centres. They take your call, find the nearest available subcontractor, and add their margin to the bill. You pay the full out-of-hours rate plus their booking fee.

Better options:

1. A local plumber you have used before. Even if they do not advertise out-of-hours, many will pick up a known customer's call.

2. Local Facebook groups or NextDoor. Post in your local area asking for a recommendation. Often a neighbour will name someone they trust.

3. Direct WhatsApp to a known local plumber. Many of us answer WhatsApp messages even outside hours. You may not get a same-night visit, but you will get a quote and a first-thing-tomorrow appointment.

For my customers in London I respond to WhatsApp messages at almost any hour. I cannot always come the same night, but I can usually tell you whether your problem is genuinely urgent or can wait, and book you in for first thing the next morning if needed.

Staying warm overnight

If the boiler is out and you cannot get someone same-night:

• Plug-in oil radiators or fan heaters work. Most run 1.5kW to 2.5kW. Effective for one room overnight. Do not leave running unattended near soft furnishings.
• Electric blankets are cheap to run and effective.
• Layer clothing. House does not need to be warm if people are warm.
• Keep moving. Cooking dinner warms a kitchen for hours.
• Close doors to stop heat escaping into stairwells.

The house might drop to 10 to 14 degrees by morning, which is uncomfortable but not dangerous for healthy adults. For children under 5 or adults over 75, prioritise getting heating restored sooner.

What I do on emergency calls

If I can attend the same night, my standard approach:

1. Diagnose the fault before discussing cost
2. Quote a fixed price for the repair before doing any work
3. Carry common parts (pumps, diverter valves, PCBs, sensors, gas valves) in the van
4. Get the heating back on the same visit if humanly possible
5. If a part needs ordering, leave you with temporary heating advice and a return time

Out-of-hours rates in 2026: £150 fixed callout (up to 11pm), £220 fixed callout (after 11pm). That covers diagnosis. Repair is quoted on top, fixed price.

When to send a WhatsApp first

Even before you call. Send:

1. Your postcode
2. Boiler make and model (sticker on the front)
3. The fault code (photo of the display is fine)
4. What you have already tried

In a lot of cases I can tell you within 10 minutes whether it is an "I can come tonight" problem, a "fix it yourself in 5 minutes" problem, or a "wait until morning, I will be there at 7" problem. Saves you money and saves me a wasted journey.