Panic sets in. A new appliance is at least £200, and the food shop is melting by the minute. The truth: one tiny part often fails before the whole machine does.
It started with a phone video. A woman in a Cardiff terrace crouching behind her wobbling fridge, filming that sharp click every few seconds, brow creased, groceries stacked on the kitchen table like evacuees. She’d cleaned the shelves, checked the dial, even slid the fridge out to wipe the floor under it. Nothing. Then a neighbour mentioned a £15 part she’d never heard of: the start relay, the little booster that wakes the compressor. The neighbour said, “Swap that and see.” She did, hands shaking, tea towel as a knee pad. Twenty minutes later the hum returned, steady as a cat purr. Ice cream saved. A tiny fix, big sigh. What if your fridge is asking for the same thing?
The one DIY fridge fix hiding in plain sight
We’ve all had that moment when an appliance dies and your brain jumps straight to landfill and delivery slots. Fridges are brutally simple in one way: the compressor does the cold magic, and the start relay helps it kick into life. When that relay fails, the compressor often clicks and never starts, or starts for a moment and quits. The cabinet warms, you blame “the fridge,” yet the fault is often that matchbox-sized relay clipped to the compressor’s side.
Think of the relay as a tiny starter motor. On many UK kitchens’ workhorses — from budget under-counter units to tall larders — this part wears out first. A local repairer in Leeds told me most “no cool, clicking” callouts end with them swapping a relay and capacitor, parts that cost less than a takeaway. One couple I met in Hackney nearly binned a perfectly good fridge-freezer because of that click. A universal replacement arrived next day. Ten minutes later, the freezer thermometer slid back to -18°C like a returning tide.
Why it fails is boring physics with human consequences. The relay feeds a burst of current to the compressor’s start winding, then steps out of the way. Heat, dust, and age make those contacts burn or the little PTC pellet inside crack. The compressor is fine, but the helper can’t help. So the system sits, clicking in frustration, while the cabinet warms, and you imagine spending **£200 you don’t need to spend**. A £10–£25 part and a calm, methodical approach can change the story.
How to replace a start relay in 15 minutes
Unplug the fridge. Pull it out with a towel under the feet to save your floor, then pop off the lower back panel. You’ll see the compressor, a black metal can the size of a small pumpkin. On its side sits a plastic module — the start relay, sometimes with a thermal overload clipped alongside. Photograph the setup. Then gently lever the relay straight off its pins, wiggling rather than yanking. If there’s a capacitor, note its two spade wires. Fit the new relay like-for-like, slide the capacitor connections back on, refit the panel, and power up. Listen for a smooth hum, not clicking.
Pick the right part. Search your model number or read the relay’s code, then buy a direct replacement or a reputable universal kit. Don’t jam a loose relay on half-seated pins. Don’t leave the back panel off because “it’s only temporary”. That panel guides airflow over the compressor and coils. Let’s be honest: nobody does this every day. You’ll feel awkward for five minutes, then oddly proud when the hum settles in and the chill returns to the shelves.
“Soyons honnêtes : personne ne fait vraiment ça tous les jours.” That line made me laugh when a French reader messaged about the same fix. This is a small job that feels big until you try it once. A veteran engineer put it like this:
“People think the compressor is gone. Nine times out of ten on a clicky, warm fridge, it’s the start device. Cheap fix. Quick win.”
- Tools: flat screwdriver, phone for photos, clean rag
- Time: 10–20 minutes for most models
- Cost: £10–£25 for the part vs. £60–£120 callout or **£200+** for replacement
- Clues it’s the relay: repeated clicking, compressor too hot to touch, no persistent humming
- Before you begin: empty the top shelf to lighten the slide-out, keep pets elsewhere
Why this £15 part can save you £200 — and your weekend
There’s a psychological trap with appliances: we trust newness more than repair. Retailers make it frictionless to replace and faintly awkward to fix. Yet fridges are built in modules. If the cabinet, seals, shelves, and compressor are sound, the weak point is often the start relay. Swapping it feels like changing a light bulb with extra steps. The payoff is real. You keep your fridge, your food, and your Saturday morning.
Some readers write in after trying “everything.” They’ve deep-cleaned the interior, turned the thermostat dial, even bought a plug-in thermometer. Then we talk symptoms. If the interior fan runs, lights are on, but the compressor only clicks and stays off, the relay is suspect. If you shake the old relay and hear a rattle like pepper in a jar, that’s a giveaway. If the fridge hums constantly but never chills, look elsewhere: dirty condenser coils, a stuck condenser fan, or a failed thermostat can mimic the same misery.
There are pitfalls to dodge. Don’t skip the basics: clean the condenser coils with a soft brush, vacuum the dust mat behind the grille, and inspect the door gasket with a strip of paper to check for leaks. A sagging seal bleeds cold air and drives energy use up. **A quick coil clean can shave 10–15% off running costs**, and it takes five minutes. Replace the relay if your clues fit; if not, pause and reassess. Fridge diagnosis is a flowchart, not a guess.
Carry this with you when the kitchen goes quiet
A tiny plastic block brought a Cardiff fridge back from the brink, and the relief was contagious — texts to the family chat, a screenshot of the part, a photo of frozen peas like a medal. Small wins travel. Share them and they stick. Next time your kitchen goes quiet and the air warms the milk, remember the matchbox on the compressor and the click that tells a story. Try the relay first. If it works, you’ve saved money, stress, and a perfectly good appliance from an early exit. If it doesn’t, you’ve still learned your fridge’s language, and that knowledge keeps paying forward.
| Key points | Detail | Reader Interest |
|---|---|---|
| Start relay is the common culprit | Repeated clicking, warm cabinet, compressor not running steadily | Clear symptom-to-fix link builds confidence |
| DIY swap is simple and cheap | £10–£25 part, 10–20 minutes, basic tools | Immediate savings vs. **£200+** replacement |
| Check basics alongside | Clean coils, inspect door gasket, verify fan and airflow | Reduces repeat faults and lowers bills |
FAQ :
- How do I know it’s the start relay and not the compressor?Listen for clicking every few seconds with no sustained hum, feel for a very hot compressor shell, and shake the removed relay for a tell-tale rattle. A dead compressor usually won’t start even with a new relay.
- Is changing a start relay safe for a novice?Yes if you unplug first, work slowly, and take photos. You’re swapping a plug-on module, not cutting wires. If anything feels unclear, stop and ask a pro.
- Which replacement part should I buy?Match your model number or the code printed on the relay. Universal kits work on many units, but a direct match is tidier and reduces errors.
- What if I replace the relay and it still won’t cool?Clean the condenser coils, check the condenser fan, confirm the evaporator fan spins, and look for frost build-up that hints at a defrost issue. No joy after that? Time to call a technician.
- Will this DIY void my warranty?If your fridge is still under warranty, contact the manufacturer first. Opening panels can affect coverage. Out-of-warranty units are fair game for this repair.
