How often should you vacuum your refrigerator coils?

Why bother

Dusty coils make the fridge work harder. A thorough-tier job. Skippable when life's busy, worth it when it isn't.

What the job involves

1. Unplug the fridge or flip its breaker. The coils are either behind the snap-off toe grille at the bottom front, or sat out as a black grid on the back. A flashlight tells you which, and how much muck is down there.
2. Vacuum the loose dust off the coils and grille with a crevice or brush attachment. This is the easy half, the stuff that lets go without a fight.
3. Work a slim coil brush, about $10, between the coils to free the packed-in dust and pet hair, and vacuum as you go. That's the bit the vacuum alone won't reach.
4. Snap the grille back on, plug the fridge in. If your coils live on the back, pull the unit out from the wall and do the panel there too. Doors shut throughout so the food stays cold.

Do it yourself, or pay someone?

Yourself, for almost everyone. A vacuum, a $10 coil brush, about 15 minutes. Some models tuck the coils away where you can't get at them, so check the manual first. Hiring it out means an appliance call-out, around $150 or more, which is why nobody pays for this on its own.

What skipping it costs

Up to about $10 to $55 a year in wasted energy, plus roughly $300 to $1,000 if the compressor packs in early. Clogged coils trap the heat the fridge is trying to throw off, so the compressor runs longer and hotter. The U.S. Department of Energy reckons dirty coils can push a fridge's running cost up by as much as 35%, which on a typical $60 to $160 a year is around $20 to $55. That waste is small. The expensive tail is the compressor wearing out before its time, and on an older fridge a $300 to $1,000 repair usually means a whole new fridge. A vacuum and a cheap brush is the other end of that.

Signs it's overdue

• The fridge runs almost without stopping, the back feels hot, and the kitchen seems warmer right by it.
• Food isn't keeping as cold as it used to, or the freezer's struggling to hold its own.
• A visible mat of dust, lint, or pet hair on the grille at the bottom front, or on the grid round the back.

When to start thinking about it

A few days' warning does it. Grumpty grumbles 2 days out, then leaves you alone. Mark it done and Grumpty sets the next one, every 6 months, so you can go back to forgetting it exists.

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