Freezer door open alarm

[Mrs Pingu]

You may have seen threads passim re:my fridge freezer not working properly. Seems like the door has been left open. Not an uncommon occurrence with the fridge.
Now the unit does have a door open alarm, but it doesn't go off it it's just slightly ajar. Obviously this is wide enough to cause the thing to freeze up when left open all night.

So, I'm looking for another solution. I'm guessing IoT would do this. I'm not capable of Arduino or Raspberry Pi so it needs to be fairly out of the box user friendly. Any recommendations?

[ian]

Dunno, but our fridge and freezer doors automatically close if left ajar. For it to stay open, you have to open it wider than a wide-mouth frog. And then the alarm kicks after a minute.

I thought auto-closing was a standard thing. It's 2017 after all, surely we're at the icy pinnacle of fridge/freezer technology.

[Kim]

My usual method is to adjust the feet so the whole thing is tilted slightly backwards, then gravity does the work.  Mostly.

I've got DS18B20 temperature sensors in the fridge and freezer compartments (connected to a Pi via some custom hardware), and alarms (it's complicated) programmed should it exceed a given temperature range.  It has to go a long time with a door ajar before the temperature exceeds normal oscillation range, thobut.  Also, temperature sensors in fridges are very sensitive to objects with high thermal mass nearby, or the absence thereof.  In freezers, the accumulation of ice around the sensor fulfils this function. 

Mostly the alarm has been useful for spotting the thermostat misbehaving so I can give it a whack, rather than catching inadequately closed doors.  What's more useful is RRDTool graphs of the temperature, which take the guesswork out of thermostat adjustment. (A single instantaneous temperature reading doesn't tell you much, as it oscillates with about a 4.5 hour period.

Basically, if you happen to have a Raspberry Pi sitting near your fridge, wired for attention-getting and logging things to a database, it's well worth the effort of stringing a couple of temperature probes inside.  If you haven't, I'm less convinced.

For a door closure alarm, I'd apply the KISS principle and aim to detect the door being closed directly.  A finely-adjusted reed switch or microswitch, or maybe something clever with a light sensor.  With a simple switch all you need to do is switch a blinkenlight or mildly annoying buzzer, so the person closing the door knows it's worked before they walk away from it.

[ian]

I'd pay a small Inuit to sit in my fridge and ensure the door is closed each time. That's what I'd do. I solve problems wholesale.

[Mrs Pingu]

Would make more sense to have a small person sit outside the fridge, not taking up valuable food space then.

[Kim]

Can't we re-train the imp who switches the light on and off?

[ian]

Inuits find our kitchen too warm. They prefer the fridge.

[Asterix, the former Gaul.]

Clearly what you need is Outuits rather than Inuits.

[Vince]

Can't we re-train the imp who switches the light on and off?

The light goes off? That's crazy talk.

[Mrs Pingu]

So no suggestions for those of us without l33t skillz in soldering and electron fettling or access to Inuits then?

[Clare]

I'd go for Kim's suggestion, tilt it slightly backwards and employ gravity.

[ian]

Inuits have always worked for me. I have no technical skills though. Everything in my kitchen closes itself, it's almost like people don't trust me to do these things myself.