Tales of the Refrigerator!!!!(Sounds bad at first, but ends well)
Tales of the Refrigerator!!!!(Sounds bad at first, but ends well)
Background: Our intention was to take 1 week or 2 week long outings at anchor throughout the summer, and after we retire, take 6 week trips at a time. Therefore, food storage and refrigeration would be a priority.
When we bought the boat, it had a small 110V bar fridge.
In addition to needing AC power, the fridge was not big enough to store a week or two’s worth of perishable food.
(Note: a “hindsight 20:20 observation”: At the time I thought there was no way to power it via AC for weeks at anchor. I discovered much later during power tests that the fridge drew 75W when on duty, which is not much when you consider that by the time the boat in the water we had 300 usable amps per day due to our combined lead/lithium set-up. Assuming a 50:50 duty cycle, the fridge would have pulled approx. 75A per day, something that could easily be recovered daily from our solar panel array. Food for thought….Now back to my story….)
Out trailer has a propane/electric stove so….. Why not get one for the boat?
My wife...ahem... I mean "The Admiral" wanted a bigger fridge than what was on the boat at the present.
I shopped around for a used propane stove and found one way up north, but the owner could not vouch for the operation of the stove. We took a gamble and drove up to get it. We paid 75 bucks for it.
I got it home and cleaned it up, then hooked it up. Sure enough, it would not work. No wonder he sold it to me for 75 bucks. The pilot would light would time-out and shut off every time it was lit. I started trouble shooting the electrics and found that the thermocouple had a dirty connector. That’s all it was. Once I disconnected it, cleaned the connections and put it back together. It worked like a charm. I ran it for several days on propane and it worked fine. Problem solved, right?....
Um.... NOPE!!
The problem started when I started doing the math on the number of propane bottles needed.
My first realization that this fridge was going to be a problem was when I downloaded the manual and specs for this fridge. The fridge needed 300W when running on AC!! Jeez, that’s a lot!!. (The bar fridge that came with the boat and wanted to get rid of was 75W!. So already this RV fridge was looking like a bad idea). Next I looked up BTU’s needed to run the fridge and that blew my mind. In short, I calculated I would go through 1 20lb bottle a week. A 40lb bottle would not fare much better. So in my mind I started to imagine how many bottles would need to be on the boat per outing, as well as the headache of constantly schlepping empty bottles off the boat, take them to the fill station and bring them back... Plus, have you
SEEN the price of propane lately?? Nuh-uh…. I ‘aint doing that!
There had to be a better way!
So I started researching battery powered fridges. I discovered “solar fridges” (its just a bunch of blah-blah…they’re just 12V fridges!). After much searching and looking at sizes and specs, we found one that was larger than the bar fridge currently in the boat and comparable to the propane fridge we just bought. The power consumption specs were good too. We picked the 6Cuft size, which was 50" in height.
This would fit perfectly in the boat, the height of the fridge would be equal to the height of the doo-hickey that is at the front of the boat.
It was expensive, but worth it in the long run. I quickly set up my data-logger and ran several tests with the fridge to verify the stated power consumption. To my surprise, my results were better than spec.
With the fridge set to “4” on the dial (dial goes from 0-7), it was pulling 30Amps in a 24hour period, and the duty cycle was 40on/60off.Water in the ice-cube-tray was frozen solid when I checked it at the end of the test.
Next I repeated the test with the dial set to 7 and I got a duty cycle of about 70on/30off and in 24 hours it pulled 50amps. I was thrilled!
Since this was almost double the size of the bar fridge currently in the boat, and it used less power AND did not need to use an AC inverter, this was the best solution. All it needed was 12V from the house bank. Yeah!!
Also, getting rid of the propane fridge and the need to constantly replace the propane bottles was also a bonus.
The best part? I bought the propane fridge for 75 bucks, fixed it, cleaned it up and sold it for $450
. I took that money and used it to offset the purchase price of the solar fridge.
Our experience with our new fridge in the 2022 season was better than we expected. I hooked up a point-of-use power monitor on the fridge and could monitor the fridge's power consumption.
As from the tests I did last winter, I have determined that the fridge in normal use will pull 30A in 24 hours, and 50A in 24 hours at worst-case setting.
Because of our solar set-up, running our fridge during the day amounts to a net-0 battery drain since the panels provide more than enough power to keep the batteries at full all day. So effectively, the load is only applied onto the batteries from sundown to sunrise. Hence, when I check my power consumption overnight, the most I ever got was 20A from sunset to sunrise. And this was late in the season when we were getting less daylight and longer nights. Considering I have a lead-lithium set-up that provides 300A of usable power that is refilled daily by our solar panels, that hardly makes a dent in my batteries.
Overall I am very pleased with our new refrigerator, its larger capacity(than what was there) and the 0 cost to power it, day in and day out.
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