British Gas confirms the real reason you must never unplug your fridge freezer

With energy bills still weighing heavily on households across the UK, the temptation to switch off absolutely everything at the mains before jetting off for a fortnight in the sun is entirely understandable. We have all been drilled on the importance of tackling ‘vampire devices’—those standby lights and idle chargers that siphon electricity—to shave pounds off the monthly statement. However, British Gas has issued a stark warning regarding one specific kitchen staple: doing this to your fridge freezer could be a catastrophic mistake that far outweighs the few pence saved on electricity.

It is not merely about coming home to a puddle of defrost water or the inconvenience of restocking. The energy giant has confirmed that completely severing power to your white goods creates the perfect breeding ground for toxic bacteria and mould that can ruin the appliance permanently. If you believe you are being thrifty by pulling the plug, think again—you might end up shopping for a brand-new appliance the moment you land back on British soil.

The Hidden Biology of Your White Goods

The logic seems sound on the surface: if you aren’t there to eat the food, why pay to keep it cold? Yet, fridge freezers are complex thermodynamic systems designed to operate continuously. When you cut the power for an extended period, you aren’t just stopping the cooling process; you are fundamentally altering the appliance’s internal environment.

British Gas experts highlight that once a fridge returns to room temperature, any residual moisture—which is inevitable in a cooling device—becomes a stagnant pool for microbes. Without the cold air circulating to inhibit growth, mould spores and salmonella can proliferate rapidly within the rubber door seals and the internal drainage channels.

"Fridge freezers are designed to be kept on all the time. If you turn them off, you risk bacteria building up inside, which can cause nasty smells and even mould. The thermal shock of warming up and then working overtime to cool down again upon your return can also strain the compressor, shortening the lifespan of the unit."

Furthermore, the foul odour developed by a warm, damp fridge is often impossible to eradicate. The smell permeates the plastic lining and the insulation foam, meaning no amount of bleach or bicarbonate of soda will restore the unit to a food-safe condition.

Holiday Mode: The Smart Alternative

Rather than risking the health of your appliance, experts recommend utilising the features built into most modern units. Many fridge freezers manufactured in the last decade come equipped with a specific 'Holiday Mode'.

This setting allows the freezer compartment to run as normal (preserving your frozen peas and emergency pizzas) while raising the fridge temperature to around 12°C or 15°C. This is cool enough to prevent the growth of mould and unpleasant odours, but warm enough to significantly reduce energy consumption compared to standard operation. It keeps the thermostat ticking over and the air circulating, preventing the stagnant conditions that ruin seals.

Comparison: The Cost of Disconnection

To understand why keeping the power on is the financially savvy move, look at the comparison below:

Action	Energy Saving (2 Weeks)	Hygiene Risk	Potential Cost
Full Unplug	Approx. £2.50 – £4.00	Critical (Mould, Odour)	£300+ (Replacement Unit)
Holiday Mode	Approx. £1.00 – £2.00	Minimal	£0
Standard Mode	£0	None	Standard Running Costs

What Should You Actually Switch Off?

While the fridge must stay on, the rest of your home is likely harbouring energy vampires that absolutely should be disconnected before you load the car. British Gas advises a selective approach to your pre-holiday shut down. Focus your efforts on devices that draw power for LED lights, clocks, or ‘instant-on’ features.

Here is the definitive checklist for a safe and efficient departure:

Televisions and Set-Top Boxes: Modern TVs draw significant power in standby to facilitate quick start-up and software updates. Switch them off at the wall.
Wi-Fi Routers: Unless you have smart home security cameras that require an internet connection, your router can be unplugged.
Microwaves: The digital clock on a microwave runs 24/7; unplugging it saves energy and removes a fire risk.
Electric Toothbrush Chargers: These are notoriously inefficient and often stay warm even when the brush isn’t charging.

Frequently Asked Questions

Does an empty fridge use less energy?

Contrary to popular belief, a full fridge is more efficient than an empty one. Cold food acts as a thermal mass, helping to maintain the low temperature each time the door is opened. If your fridge is empty before a holiday, consider filling jugs with water to help stabilise the temperature.

What if I don’t have a ‘Holiday Mode’?

If your appliance lacks this specific button, simply clear out all perishable food and turn the thermostat to its warmest setting (usually 1 or the lowest number on the dial). This reduces compressor cycles while maintaining enough airflow to prevent mould.

Can I unplug it if I leave the door open?

Technically, yes. If you absolutely must unplug the unit, the door must be propped widely open to allow full air circulation. However, this is risky as doors can accidentally swing shut, and it often requires defrosting the freezer manually first to prevent flooding your kitchen floor.