Standalone Fridge Door Sensor

A fridge door left ajar is a slow, expensive accident. Nobody notices until the milk has turned and the freezer has thawed. This is a small white fridge door alarm that notices for you.

• Why a fridge door alarm is worth the money here
• It escalates rather than shrieking
• Four volume modes, set with one button
• Fitting it, and checking the gap
• What it fits

Why a fridge door alarm is worth the money here

A door left on the latch does not announce itself. The compressor runs and runs, the freezer creeps up, and the first anybody knows is spoiled food and a bill. In a climate where the difference between inside and outside the cabinet is thirty degrees, a fridge standing ajar for an afternoon is not a small waste. In a shop, a bar or a guest house with staff in and out of the chiller all day, it is a weekly event.

It escalates rather than shrieking

That is the design decision that makes it liveable with. One minute ajar gets a two second beep, which is a reminder and nothing more. Two minutes gets four seconds. Only at three minutes does it stop being polite and sound for a full minute. In loud mode a 110 dB siren then joins in every four minutes until somebody shuts the door. An alarm that goes straight to maximum is an alarm that gets a battery pulled out of it in a week.

Four volume modes, set with one button

Quiet at 80 dB, medium at 85, normal at 90 with a beep every ten seconds, and loud at 95 with the siren behind it. The SET button cycles them and confirms with four beeps. A kitchen fridge in a flat wants quiet; a chiller at the back of a shop wants loud.

Fitting it, and checking the gap

Two parts, double sided tape, no wiring and no app. It beeps quietly if the two halves are too far apart, so you can hold them in position and confirm the alignment before you peel the backing off. That saves the usual routine of sticking it down twice.

What it fits

Fridges, freezers, chillers and cold rooms. It is a small white unit that does not look out of place on a kitchen appliance, and it does not need a fridge with any electronics of its own.

For a door you want reported to your phone rather than announced in the room, the WiFi door sensor is the one, and for a cold room where the temperature itself matters the WiFi siren carries a temperature and humidity alarm that works offline. Wikipedia covers how refrigerators hold temperature if you want the background.