I am (hopefully) acquiring a 356 and had a question about electrically frugal use of the fridge freezer units. As I understand it, the fridge works off cool air fanned from the freezer, so the freezer has to be colder for the fridge to work. What if I leave the fridge thermostat off and set the "freezer" to just fridge temps? I don't really need the freezer function for weekends. Would this work and use less juice?
Fridge/freezer use
- Thread starter danm1
- Start date
Worked for me once as an interim solution when we needed to effectively double our refrigerator size and not need the freezer. If your goal is to decrease battery draw, I don’t see how this will save you very much power.
Thought cooling a smaller area at a higher temp would help unless there was too much leakage to the fridge compartment even with fan off or some other quirk of the design I don't yet understand.
One of your biggest energy savings will be a tight lid. Use the dollar bill test to make sure you have a good seal for the lid.
Refrigeration compressors actually use more "juice" at higher temperatures even though it's minuscule in these machines.
You would probably do better with a thermal Mass like a couple jugs of Frozen water in the freezer compartment because what is cold wants to stay cold especially Frozen liquids
You would probably do better with a thermal Mass like a couple jugs of Frozen water in the freezer compartment because what is cold wants to stay cold especially Frozen liquids
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And don't forget to plug the drain hole at the bottom so all that cold air does not flow into the bilge.
The cold air inside the refig/freezer is heavy and drains down through the drain hole into the bilge. A slight vacuum is created and the air is replaced by warm air drawn in (leaking) around the top gasket on the lid. The effect will be minimal if your gasket is good and well fitted. If not, there will be frost build up on the cold plates and freezer.
This could then be solved with noting more complex than a trap - a "U" shaped bend in the fridge drain hose that holds water, but prevents gases (cold air) from passing. No?
That would work, but it might be difficult to know that the "trap" had water in it, unless it was transparent and could be inspected.
This is a very important point, thanks for making it.
In the "land based" plumbing world, there is a feature called a "trap drain primer." It is used where there are floor drains, for example in larger toilet rooms where a floor drain is installed to permit maintenance staff to clean the floors with lots of water and drain it easily and efficiently. Since that deep cleaning may not be done daily, whenever there is the possibility that a trap could dry up before its next use, a trap drain primer is installed. This feature shoots a bit of water into the pipe above the trap to keep the trap wet. If a trap dries out, it permits sewer gas to intrude.
On a boat's fridge, a dry trap will not do this, of course. However, a dry trap will not stop cold air from leaking out either.
Tedd's right.
Why bother with a trap at all? Suggesting it indicates a complete lack of understanding of basic plumbing functions because they simply shouldn't apply to a boat fridge: why would you want or expect water to be inside your frridge - it just means it's leaking air.. Just close off the hole at the bottom of the fridge. If you must, either put a removable cap on it or a valve.
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After 10 years of that same refrigeration set up, here is my best compromise/most used solution. H410
I keep my freezer side at 31/32 and the refrigerated side fan on, on the highest setting I have.
The refrigerater fan kicks on at 49 and turns off at about 42. When the fan kicks on drawing from the freezer the temp goes from 32/32 up to about 38 till the fan turns off at which point the temp slowly drops back down to 32.
I can keep a bag of ice forever (drinks) I don't need to freeze food, but like some meats, drinks, alcohol or frozen food's along (stay frozen it seems on bottom)
My milk does freeze in freezer side though.
The refrigerated side holds eggs, veggies, cheese, condiments more drinks, water anything that we think should be cold.
My compressor (newer) seems to work about about 15min every hour, the fan about the same, all at 3.5ah so, it seems it's taking about 1 amp per hour?? Now that all really depends a lot on outside temps and how often you open /close and having the boxes filled with cold items helps.
I need to defrost right now every 3 weeks, easy, just turn off compresser at freezer thermostat and let the refrigerater fan do it's magic, keep it all closed, food stays cold and the plates will be free of ice in about 4 hours +-. I put a washcloth somewhere near the bottom of the freezer to soak up liquid.
Everyone has their own plan, just sharing mine.
I keep my freezer side at 31/32 and the refrigerated side fan on, on the highest setting I have.
The refrigerater fan kicks on at 49 and turns off at about 42. When the fan kicks on drawing from the freezer the temp goes from 32/32 up to about 38 till the fan turns off at which point the temp slowly drops back down to 32.
I can keep a bag of ice forever (drinks) I don't need to freeze food, but like some meats, drinks, alcohol or frozen food's along (stay frozen it seems on bottom)
My milk does freeze in freezer side though.
The refrigerated side holds eggs, veggies, cheese, condiments more drinks, water anything that we think should be cold.
My compressor (newer) seems to work about about 15min every hour, the fan about the same, all at 3.5ah so, it seems it's taking about 1 amp per hour?? Now that all really depends a lot on outside temps and how often you open /close and having the boxes filled with cold items helps.
I need to defrost right now every 3 weeks, easy, just turn off compresser at freezer thermostat and let the refrigerater fan do it's magic, keep it all closed, food stays cold and the plates will be free of ice in about 4 hours +-. I put a washcloth somewhere near the bottom of the freezer to soak up liquid.
Everyone has their own plan, just sharing mine.
I do happen to have a very good understanding of basic, and some advanced plumbing, having rehabbed/renovated multiple houses and boats.
Uh, ice melts. If there wasn't water in the fridge, why would there be a drain? Suggesting so indicates a complete lack of understanding of basic boat cooler and refrigerator operations.
Seriously, Stu - why so harsh?
I don't know about anyone else, but every boat I've ever been on that had a built-in cooler, ice box, or fridge had a drain in the bottom. This was to drain - wait for it - water. Water comes from melting ice, either from blocks of ice or bags of cubes you put in there to keep or to augment the refrigeration system, if you have one; and also from condensate, which happens when moist air meets cold items. So, expect water in your fridge.
I had a trap on my previous boat, and it quickly filled with water when the fridge was used, and stayed that way as long as the fridge was used. Water drained easily, and cold air didn't spill into the bilge.
By the way, this isn't an original idea, as a google search will reveal.
"A fridge also needs a drain, but a simple open hole at the bottom will allow the cold air to quickly seep out. To prevent this drains should have a pump, tap, plug or “U” bend filled with water."
That "U" bend filled with water is a trap.
How to: Upgrading Your Icebox
That "U" bend filled with water is a trap.
How to: Upgrading Your Icebox
Or you could just toss a cup of water into the icebox. But I assure you, if you have ice and condensation in there, it won't be necessary.
Because the discussion was about refrigeration, not ice boxes (i.e., coolers). For 25 years I have had a fridge and don't have standing water in the bottom. And I ain't gonna start throwing cups of water into it, either.Uh, ice melts. If there wasn't water in the fridge, why would there be a drain? Suggesting so indicates a complete lack of understanding of basic boat cooler and refrigerator operations.
Seriously, Stu - why so harsh?
Harsh? No, realistic. If you can't differentiate between ice box and fridge, at least mentioning you're talking about one while this thread is about the other, then why blame me for simply pointing it out?
I simply capped the hole at the bottom.