brunnhilde's refrigerator control - part 10

 

I did some final things to wrap up the Ink Bird cum refrigerator control for the Dometic fridge. I met all the goals I set out and the out of pocket cost is just $13. I open up the compressor compartment again to put in the CPT module, and a piece of note of instruction on how to revert back to the Westfalia Central Electronic Console should the Ink Bird fail on the road. It is very easy to forget all these a few years down the road.

"for your eyes only" secret document; open only in case of fridge emergency

this was how tidy it was when I last button it up; actually a panel is removed to reveal the tidy harnesses

the brown wire with the female spade lug is the T control from the Central Electronic Console that is not used now

I secure the secret instruction and the CPT module in a plastic bag and zip tied to the wire bundle

this is where I located the NTC thermistor for the Ink Bird; it will be secured with foil tape to protect it

I held off ordering this 3 meter long thermistor and am glad I did as it would not help the long cable run; the 4 conductor landline cable worked out perfectly

someone still selling this long EOL reed rely that I used

my normal set point is 32F or 0C which requires very few LED segments to be lit so minimal power consumption; I set the dead band to 1.5 C and a one minute of compressor lockout

the external digital thermometer is now decommissioned

the best modifications are the one you cannot see

So this wraps up this little project, and I am pleased with the result, and cleaned up the clutter with the external thermometer. that is bad place to mount the thermometer for cabin temperature as I would found out as the black window behind it generates immense solar gain. I plan to add some fiberglass batt insulation around the refrigerator tub next time I go to Home Depot. 

while reviewing the fridge design, I added a piece of 1/4" foam board above the condenser which will slow the heat transfer into the tub, especially with a fan air flow upwards

The digital thermostat for the Coleman AC is working flawlessly. I could not imagine the difference it makes in comfort where the mechanical control cannot. When working inside like installing and testing the Ink Bird for the fridge I can turn on the AC and be comfortable. Next I plan to tame the excessive noise of the condenser fan on the roof top assembly.

As I am writing about tidy up part of the project which involves wiring, I want to say something about cable ties. I cannot stand sloppily cut cable ties. For me there are only two acceptable way. One is to leave the tail not cut. The other is to take the care to cut it absolutely flush against the barbed head. I do the latter the most often. You cannot achieve a good flush cut with cable tie guns. I do that with a good precision cutter. A poorly cut cable tie ends are nuisance and can cut your skin open, and look unprofessional. I had use cable tie gun and they are handy in tight spots for tension it well. However I seldom let it do the cutting.