freezer hacking and farm coolers

early harvest

ok, so i did not find some old freezer for free on the corner, but we successfully completed the ubiquitous freezer hack.

we want to be able to store a large quantity of veggies in a fridge that cools things quickly.  why? in order to deliver great veggies you want to cool them down as quickly as possible – sometimes from 90 degree field heat.  we also have a weekly delivery and we are fast learning that things left unharvested to coincide with delivery date can turn bad. it is also great to load super cold produce into coolers for the 2 hour drive down to the city.

plan A was to build a walk in cooler in a corner of the garage out of a bunch of home depot insulation and solid outdoor well sealed door.  we would use the cool bot to conrol an AC and have a cheap ($1500?) cooler to store veggies.  this was going to take a lot of time to build and frankly felt like overkill.  the idea of a huge / half empty cold room seemed silly.  plus we want to be able to use a cold cellar in the future and possibly just have electricity to get field hot greens down in temp.

freezer plugged into external control & killawatt

we opted to buy a 25 cu ft. freezer chest that has the better insulation of a freezer and is top loading so every time you open the door the cold air does not pour out like a front opening fridge.  rather than hack the thermostat on the freezer we decided to go with an external thermostat to drive the freezer as a fridge.  this gives us the future flexibility of easily using the freezer as a freezer.

all you have to do is set the freezer on full and plug it into another thermostat that turns the freezer on and off with in a 4 degree range of the selected temp.  the 4 degree variation  limits the number of times the compressor turns on and off to prolong its life.  we also took out the incandescent bulb that came inside the freezer – effectively a little heater inside the freezer.  god bless america.

external thermometer
its big

frigidaire GLFC2528FW – 24.9 cu Ft. Manual Defrost chest freezer for $640 including delivery

johnson controls manual thermostat control unit for $60 on amazon.

so total cost for something substantially smaller but arguably more efficient than the home made cooler was $700.  we will see how the lifetime and our needs evolve, but i am feeling good about this investment as far as versatility and hopefully scalability.

now for the details:

everything was working great except the temperature alarm on the freezer was going on when its internal thermometer read above 32 degrees, thus the fridge was beeping every time the compressor ran.  fortunately the unit did not need to run much because of its decent insulation.

what follows is a step by step of removing the alarm in case anyone goes down this path themselves.  need a screw driver and solder iron.  desoldering pump and braid would have been smart.

open the side panel
locate this box in back left - not alarm is behind hole on upper right of box
unscrew first mount screw
remove power cable from box and second screw
unscrew 4 screws and remove circuit board from inside box and locate alarm - labelled BZ1 - in this pic it is the circle in the lower right - unsolder the alarm
watch cables pulling circuit board out of case
empty spot from unsoldered alarm on bottom of board - not pretty
the removed alarm - the braid that absorbs old solder would have been useful

One thought on “freezer hacking and farm coolers

  1. Hi there farmer. I’m in a similar situation of needing an efficient, but not giant, cooler and I’m really curious how your freezer hack went. I found you post in a totally vague google search and I’m glad I did! Please let me know if it stood the test of time!

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