I’m not brilliant at remembering what temperature different things should be, which is why, if my husband takes a thermometer out of his mouth, shivers violently, wipes the sweat from his brow and says “aaah… 40.3 ….” he might as well be reciting limericks in Urdu for all the sense it makes to me.

I find a simple “sssshhhh, I’m trying to listen to The Archers” normally does the trick and he tends to fall back into a refreshing sleep or light coma, depending on how the flu is.

But when I walk into the utility room and spot a red light flashing on the fridge freezer, and get closer and see the number 14 with a big exclamation mark on the temperature gauge, even I pause and rack my brains. Can that be right?

Fourteen sounds on the high side for a fridge temperature in anybody’s book. I open the door. Clearly, the fridge agrees with me. I’m not saying you could exactly heat soup in it, but I’ve had colder summer breaks in Wales.

I press a button on the panel at the top, and the 14 changes to minus 4. Well, technically the bottom bit is still a freezer, then. But a little neuron in the place in my head where I store all my memories of school and girl guide camping holidays half-heartedly fires up. It reminds me that our cookery mistress once insisted that, were any of us ever lucky enough to marry well and be able to afford a domestic freezer – this was the days when entire neighbourhoods shared a phone which they kept in a glass kiosk on the street and you could have any colour telly you liked as long as it was black and white – it was important that it was maintained at minus 18 degrees.

The fridge freezer is broken, I call up to my husband. He comes downstairs and sighs at it. The fridge shows no sign of being influenced by that at all.

The fridge bit is running at 14 degrees, I tell him.

What? He asks. The fridge bit is running at 14 degrees, I repeat, louder. Fourteen degrees what…? He says.

Degrees what? I don’t say anything for a second or two while I collect my thoughts.

This is a trick question, and I can never remember the right answer. It’s absolutely definitely not Fahrenheit – that involves long division and taking away 32 and stuff – but after that I’m on dodgy ground. I go for it. Centigrade, I say.

He sighs. Kelvin? I add quickly. Oh dear, I can see I’ve failed. Celsius, I finish, defeated.

Then I get a grip. If we can accept that I will never be a viable candidate for a doctorate in physics, however much I watch programmes with Professor Brian Cox in, I say, perhaps we can move on to the problem in hand.

The milk is going off. The gin in the freezer is getting unpalatably warm. The 20 portions of vegetable curry I put in the freezer at the weekend are at risk of thawing out and we’ll have to eat them all tonight.

He sees my point, and begins to try to move the 6ft high appliance away from the wall. As he does so, half a dozen mops, two pieces of wood and a small stepladder fall out from behind the fridge and hit us on the head.

I retreat to Google Hotpoint Mistral freezer, while he gets out the first aid box. Looking for a thermometer, no doubt.

There are lots of things that can go wrong with fridge freezers, it seems. Especially ones like ours that are more than 15 years old.

Condensers, fan blades, thermistors…. the list is almost endless. But it does end.

With the words cat hairs.

I go back to the utility room, where my husband is pretending to be an electrician. Try cleaning the cat hairs out of that front panel, I say with authority.

He gets out the vacuum cleaner and tries it. A slow but certain hum fills the room, as the fridge freezer comes back to life.

There you are, I say, like a fully qualified domestic appliance engineer. Amazing what a bit of hoovering can do.There’s a pause.

It’s a Dyson, not a Hoover, he says.