Sciencemadness Discussion Board

Scored a fridge freezer!

NEMO-Chemistry - 3-7-2016 at 12:53

Some friends of the family have a new kitchen, apparently their old fridge freezer (working) is going to cost £30 to have taken away!

So i have offered to do them a favor and take it off them if they help load it into another friends pick up. So i need a bigger shed! Actually i am well made up i have a fridge freezer for storage and chemical use :D.

Its old and a bit grotty, which makes it PERFECT!

Ether etc i will put in bottle in sealed plastic box's incase of electric sparks. But feel happier i can keep some of the higher vapor stuff alot colder.

Also have a kind of solar powered drying box nearly finished, needs a bit more wood and insulation. I might end up with a cobbled lab at this rate.

Also Friday last day of term i was given some glass stuff from the chem techs at school having a clear out!! a couple of 2 ltr conical flasks and some old school round bottom flasks and a few bits :D

DJF90 - 3-7-2016 at 14:08

Don't store flammables in a fridge/freezer not designed for that purpose, even in secondary containment. Usually the issue is the light fitting, so if you can eliminate that then you may be ok (this is what was done at a former company that I worked for when they didn't want to splash out for "lab grade" refrigeration).

CharlieA - 3-7-2016 at 15:12

This is a good point about the light fixture causing sparks. Also, I wonder about the thermostat mechanisms also sparking. Are they perhaps solid-state thermostats in modern fridge/freezers?

NEMO-Chemistry - 3-7-2016 at 16:01

no light in the freezer part, but thermostat i dont know. I know our fridge has one in the fridge bit but i can only see a thin copper tube in the freezer bit. Not too sure how these things work....

My other option is to use the fridge for chilling down etc for crystallization and keeping HCL etc cold. the freezer part maybe just my plastic bottles of anti freeze i use in my water baths.

I wonder if i could use a coil from the freezer part to the old fridge i have with no electrics or parts in it, not sure how cold it would get though.

If the freezer part dosnt have a source of ignition, then i take it i dont need to worry about the compressor or other bits outside it?

Only way to be sure is try and find info on what the proper ones do differently and see if there is anyway to copy it. failing that then its just acid's and stuff to chill down, i will keep the ether and other solvents out of it.

I hadnt thought about the light, will get it Tuesday i think so let you know what its like and take some pics. I would hate not to use it if i can make it safe enough

macckone - 3-7-2016 at 21:34

Most refrigerators of modern manufacture should be fairly resistant to igniting flammable vapors.
Apparently this is because non-chemist routinely store high proof alcohol in them.
This is not the same as explosion proof.
There are two sources of ignition.
The door open switch and the thermostat.
The motor is completely enclosed.
If the lightbulb is in properly it won't spark but the switch might.
Removing the light bulb will prevent a complete circuit.

NEMO-Chemistry - 4-7-2016 at 01:42

Quote: Originally posted by macckone  
Most refrigerators of modern manufacture should be fairly resistant to igniting flammable vapors.
Apparently this is because non-chemist routinely store high proof alcohol in them.
This is not the same as explosion proof.
There are two sources of ignition.
The door open switch and the thermostat.
The motor is completely enclosed.
If the lightbulb is in properly it won't spark but the switch might.
Removing the light bulb will prevent a complete circuit.


I dont need a light! so i can disconnect all that, the freezer part has no light so thats ok! Something i found out reading was fridges are very low humidity inside, so good place for a desiccator for plant stuff?

Looks like i can have some garage space (woohoo), this will make chemistry much easier! My shed is pretty small and no constant power, dragging a extension lead outside across the drive is a pain.

I have had a car drive over it more than once! Hotplate stirrer arrived today along with a few bits, not many chems but i can make a good few with those i have.

Rather spend the money at the moment on glassware

macckone - 4-7-2016 at 06:41

Yes, low temp desication is possible.