Results 1 to 6 of 6

Thread: Older deep freeze low efficiency for electronic circuit testing.

  1. #1
    Join Date
    Jun 2018
    Location
    Canada
    Posts
    3

    Default Older deep freeze low efficiency for electronic circuit testing.

    Hi, this is not a repair question, more of a what brand and model to purchase question.

    Iím an electrical engineer in need of a cold chamber for electronic circuit testing and would like to modify an used deep freeze for this task. Industrial heat/cold chambers exist for this purpose, however they are very expensive. Some on a budget are using incubator chambers that can cool down to about 2C, however only when not dissipating any significant heat.

    I have little knowledge of refrigeration however Iím comfortable taking anything apart and modifying as required.

    Iím looking for an older model about 1-3í cubed that is capable of cooling to ideally -40C if I bypass the original thermostat and retrofit a custom thermostat. Power dissipated by the DUT (device under test) would be less than 25W, often much less.

    I would imagine the newer high efficiency models would be the opposite of what Iím looking for, more likely and older ďover engineeredĒ model that could cool quickly would be a better candidate.

    Can anyone recommend brands and models that would be a good candidate?

  2. #2
    Join Date
    Oct 2004
    Location
    Ontario, Canada
    Posts
    22,220

    Default

    Hi,

    I’m looking for an older model about 1-3’ cubed
    1 to 3 cuft?

    Chest freezers started at 4(rare) - 5(more common) cuft and smallest upright that I have seen is 5 cuft.

    capable of cooling to ideally -40C
    That may be hard as most where designed to get to -18ļC which is 0ļF. With the control bypassed it will definitely get colder but I would be unsure if any could maintain -40ļC. AN chest freezer might be best because the cold will stay in the cabinet even with the lid open while an uprite style the cold air falls out when the door is opened.

    WCWoods is now out of business but their Made in Canada and USA models where some of the best freezers in the world!

    This is a 5 cuft one...

    Click image for larger version. 

Name:	CF05WL.jpg 
Views:	0 
Size:	22.0 KB 
ID:	38378 Woods CF05W 5.3 cu. ft. Chest Freezer with Manual Defrost

    jeff.
    http://www.applianceaid.com/
    Appliance Repair Aid
    Yeah I've got O.C.D.....Old, Cranky and Dangerous.
    Tip of the day, set your Samsung Smart Fridge to a foreign language so Google can't spy on you!!

  3. #3
    Join Date
    Jun 2018
    Location
    Canada
    Posts
    3

    Default

    Thanks for that. I can make space for 5cu. ft.

    I will probably try to simply bypass the original thermostat and then add a thermocouple and an external thermostat control that simply cycles power as required to control the temperature. From what I have read, the compressor needs some "leak down" time before restarting, any idea how long this is typically?

    I plan to make a two cut outs, one will be a 2" conduit to pass wires in and out while closed, and the other a small window (triple pane) for observation. I did a google search for exploded diagrams of freezers to see where the cooling lines are placed, looks like everywhere except the door. So window in the door and conduit probably high in a corner, obviously I will need to look carefully before drilling/cutting.

  4. #4
    Join Date
    Oct 2004
    Location
    Ontario, Canada
    Posts
    22,220

    Default

    From what I have read, the compressor needs some "leak down" time before restarting, any idea how long this is typically?
    Pressures need to equalize in the system ( between low side and high side ) before the compressor can restart back up once it has shut off. This normally takes around 8 minutes.

    jeff.
    http://www.applianceaid.com/
    Appliance Repair Aid
    Yeah I've got O.C.D.....Old, Cranky and Dangerous.
    Tip of the day, set your Samsung Smart Fridge to a foreign language so Google can't spy on you!!

  5. #5
    Join Date
    Jun 2018
    Location
    Canada
    Posts
    3

    Default

    Thanks. I will keep the 8 minutes in mind.

    Any idea where I can find a schematic for whatever freezer I find, or our they printed on the back of the unit?

  6. #6
    Join Date
    Oct 2004
    Location
    Ontario, Canada
    Posts
    22,220

    Default

    *Normally* printed right on the unit.
    A freezer is very simple in wiring.

    jeff.
    http://www.applianceaid.com/
    Appliance Repair Aid
    Yeah I've got O.C.D.....Old, Cranky and Dangerous.
    Tip of the day, set your Samsung Smart Fridge to a foreign language so Google can't spy on you!!

Similar Threads

  1. Kenmore range - testing electronic control board?
    By baseballsmitty in forum Sears Kenmore
    Replies: 1
    Last Post: January 12th, 2015, 09:41 PM
  2. Old Hotpoint 25 Deep Freeze
    By mrfoo in forum GE/Hotpoint
    Replies: 1
    Last Post: September 7th, 2013, 09:08 PM
  3. Deep Freezer Won't Freeze
    By Handy-Capped in forum Refrigerators & Freezers
    Replies: 3
    Last Post: November 24th, 2010, 11:59 AM
  4. Older Kenmore wont freeze or get cold past 50 ish.
    By 18dpa in forum Sears Kenmore
    Replies: 3
    Last Post: January 10th, 2010, 01:30 PM
  5. FA Deep Freezer Thawing Out!!! HELP
    By GameTraxx in forum Frigidaire/Electrolux
    Replies: 3
    Last Post: June 23rd, 2007, 10:01 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
If you feel that you have benefited from this site, and would like to show your appreciation, you can throw a buck or two in the Appliance Blog Tip Jar - Thank you!