Thermal Mass Differences
Okay, sorry for the delay in postings but I have been busy,lazy and needed some time to gather and put things together.
So a few things, two previous logging runs I have not posted, I am not sure what happened with the probe. I may have hooked it in the wrong channel. I had some very strange readings, one being a temp run in the 250 degree range. I think that was me pluggin it into the wrong channel port. I also had another run where the fridge didn't get past 60ish, but I think that may have been because it was left in my garage when it was 82 outside. It got hot I am guessing inside the garage. I really think I am going to put another probe in the mix to gather outside ambient temp. It would really help tie together how this compressor reacts to outside temp and how much delta T comes into play.
So, that aside, I managed to get a test run of the fridge full on temp setting #4. I had the fridge running all night on temp #3, cooling down, everything ready to go for a #4 run. I wanted to make sure the fridge was cooled down enough. In previous testing, running the fridge full right out of the gate without any previous cooling to setting #4 hasn't been very spectacular. With the fridge full it seems to put a hell of a load on trying to get the fridge down to temp. Further testing will need to flesh this phenomenon out.
So, back to the task at hand, comparing the difference between a fridge lightly loaded to fully loaded and how the temperature differentials contrast. I took a snap shot of a previous test run and a fully loaded test run at temp setting #4. It's a time span of about 3hrs. With the fridge near empty, the temp was still dropping down, the downward slope was much steeper than was the fridge full slope. The downward slope of the Full Fridge was very gradual, it was dropping but nowhere near as fast. However, you can clearly see the difference in temperature swings. The full fridge is much much flatter. The contents in the fridge being cold helped keep the swings low(thermal mass). The amperage draw was pretty much the same, low and consistent. I was wondering if voltage mattered, I don't think it did since the near empty test was done using 12V and the full test was done using 110V, just a sidebar I was concerned about.
I do plan to do more testing regarding thermal mass. I have a cookout down at the lake this Saturday that I plan to do some test runs while I am out and about. I also plan some tests using frozen bottles of water since it has often been mentioned in posts that folks do this to help out the fridge AND provide cold water for drinking.
In the works is a transit bag test. I am working on getting a bag. I think that the transit bag testing will help illuminate the benefits of having the added insulation. But time will tell.
Here is the
thermal mass comparo