Power cuts are never fun — especially if they hit in the middle of winter, just as your heating kicks in. But beyond the cold and inconvenience, many of our customers ask:

“Can a power cut actually damage my boiler or heating system?”

Great question — and one we’re asked a lot. So here’s everything you need to know about what happens when the lights go out… and whether your heating system is at risk.

What Happens to Your Heating in a Power Cut?

Most modern heating systems — even gas boilers — rely on electricity to function.

• Combi and system boilers need power for the control panel, pump, and safety sensors.

• Smart thermostats, programmers, and motorised valves all stop working without power.

• If you’ve got underfloor heating, that’s typically electric (or has electric controls), too.

So in a power cut, your heating shuts down — not because it’s broken, but because the key components have no power.

Can a Power Cut Damage Your Boiler?

In most cases: no, a standard power cut won’t damage your boiler.

But there are a few risks to be aware of — especially if the power flickers back on and off, or if there's a surge when it returns:

1. Electrical Surges

When the power comes back suddenly, a voltage spike can hit sensitive components like circuit boards, thermostats, or pumps.
That’s why surge protection is now recommended — and included in all new consumer units.

2. Frozen Pipes

In a long outage during freezing weather, there’s a risk of pipes freezing if your system is off for hours.
That’s where frost protection settings can help — but they need power to work.

3.  System Memory Loss

Older boilers or smart thermostats might lose their settings or schedules after a full reset.
Most modern systems have battery backup or non-volatile memory to prevent this — but not all.

What Should You Do After a Power Cut?

Once power’s restored, here’s a simple checklist:

1. Check your boiler display – Is it back on? Any fault codes?

2. Reset if needed – Some boilers need a manual reset after a power outage.

3. Check timers/thermostats – Re-enter any schedules if they’ve been wiped.

4. Inspect for leaks or strange noises – Unusual signs might indicate a fault triggered by the outage.

If your boiler doesn’t come back on, or shows a fault code — give us a ring. We’re happy to help diagnose or pop out if needed.

How to Protect Your Heating System

Here’s what we often recommend to customers in and around Exeter:

Fit a Surge Protection Device (SPD)

If you’re upgrading your consumer unit, this is now standard — and it can protect not just your boiler, but all your home’s electrics.

Keep Your Boiler Serviced

Regular servicing helps spot issues before they become real problems. We often catch failing components before they’re affected by a power event.

Consider a Battery Backup (UPS)

Not always necessary, but in rural areas with frequent cuts, a small UPS for your controls or router can keep things stable.

Join a Service Plan

EPM will soon be offering service plans with cover options for electrical faults, heating repairs, and more. Perfect if you want added peace of mind without big call-out costs.

Final Thoughts from EPM

Power cuts are part of life in the UK — especially in stormy weather or rural areas.

While they rarely break a boiler outright, they can lead to electrical faults or frozen pipes if left unchecked. If you’ve experienced a power cut and something doesn’t feel right with your heating, don’t ignore it.

We’re here to help — whether that’s a quick reset, an electrical check, or getting your system back up and running safely.