Running Waco / engel / etc as a freezer.

It works better if it's full rather than empty

We use a Waeco CF40 as a freezer, running at about -15. I've never measured the duty cycle, but I'd guess it normally runs about 50% once it's cooled down. I'm not sure there's any benefit to turning it off at night - it will only run all the harder the next morning to catch up.

Southace,
I've got a cf40 portable Waeco which i run as a fridge most of the time just to keep a few beers cold. I also have 2 built in iceboxes in the cockpit which offer much more space. On longer trips I run the Waeco as a freezer, and freeze 2 litre milk jugs of water to keep the icebox cold.

Keeping the Waeco full does make it more efficient, although it will run still run most of the time until the jugs of water are frozen. My Waeco came with a zip-on insulating jacket as well. I expect it improves the efficiency.

I usually start out by freezing a bunch at home, then only need change out a couple jugs a day in the ice box while cruising.

We've got a Waeco which came with a fancy dust cover which I was going to throw away because I dont like clutter on boat.

Then I read the dust cover is designed as part of the Fridges insulation and the fridge will work better with it.

So I took it out back out to boat and covered the Waeco and sure enough much less battery use. (Set to 4DegC for beer).

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Trek said..

HG02 said..
Salt water also holds ice better than fresh

Ahh hemm ... HG

The heat capacity of freshwater is 4.182 J/(g K) and the heat capacity of saltwater is 3.993 J/(g K). Therefore, saltwater will heat up and cool faster than freshwater!!

Sorry My English wasn't my best subject
Salt water has a lower freezing point than fresh That was my thought but I was wrong

Pure water has a freezing point that is constant. It is 32 degrees Fahrenheit. When a substance is added to the water, it does two things.Lowers the freezing temperature of water Varies the freezing temperature of water - this is why the melting rate of water sprinkled with sugar is different from the melting rate of water sprinkled with saltIn both cases, the temperature is lowered, which is why salt is put on roads during freezing temperatures. It means the water on the road will not freeze, even though the air temperature is cold enough.The chemical nature of the substance that is put on ice, however, is not an important factor. Instead, the number of molecules determines how fast or slow the ice melts. This is known as a colligative property.Assume there is the same measurement of salt and sugar - one tablespoon. There are more molecules in the tablespoon of salt than there are in the tablespoon of sugar. This is why the tablespoon of salt melts ice faster than the tablespoon of sugar.

When buying ice years ago Id take it home and put it in the freezer over night to bring the temp down as most retail outlets just have the ice temp set at freezing piont

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southace said..
I love the idea of layers of newspaper hmmm steaks,pork chops, lamb, roasts, mince should keep me going for 3 weeks or so on the pick over Christmas! dunno about the draw fridge ho2 that would loose a lot of cold air once you pull it out and select what you want!

That's what i thought to .
But as a weekend fridge as long as you didn't open frequently would be OK and you could also wrap more insulation around it
Id rather make ice and use a good Esky in the cockpit no matter what fridge you have on board get what you want out of it quickly and close it up asap.

I love those draw fridges. Was gonna buy one but at 800 for the engel draw i thought id get the waeco. I love the waeco but thise draw fridges seem practical and would use less space.

G'day ACE. First post as a Seabreeze member.
I suspect that I'm reasonably competent to contribute having been on the hook 24x7 for over 7 years now.
Six years ago I bought my first fridge, a Waeco CF18. (mistake based on dollars). The bottom of it rusted out within about a year causing water to drip out
onto the electrical components. I only used as a fridge and it drew 3.75 amps and it cycled at about 50% rate (running 12 hours per 24 hour period.
So I bought another Waeco CF18.....same story about 14 months later. But in the last 8 months of it's life I cranked it up to -15 freeze mode.
Then I bought an Engel 38L Eclipse with the insulated protector cover. The Engel too cycles @ about 50% duty cycle but it draws an Amp less.
Now, over three years later, the Engel hasn't missed a beat and I lift the (full of food) basket out about every 12 months for a ten minute defrost'
FWIW, my battery capacity is 480AH as a single bank.
Hope this was useful.
Cheers Brian

Some great experience thanks guys.

so currently my freezer is running from -15 down to -13 every 10 minutes at 3.4 amps while empty.

i will attempt to stock it over the next 2 months starting with 2 litre milk bottles then layers of meat and newspaper.

hopefully this will change my run times to -15 down to -13 every 30 minutes at 3.4 amps while full this should be 50% run time?

So 50% should be 12 hours X 3.4 amps = 40.8 amps over a 24 hour period.

So my fridge and freezer should draw approx 80 to 100 amps in a 24 hour period.

With approx 15amph X 8 = 120 amp solar input over a 8 hour period I should only just get by!

Perhaps I should give up eating meat and just eat fish!

Na me and Cat drink a lot of milk and it's only $2 a bottle at Coles! :)

Something I forgot to mention. As I said, when i bought my Engel i also purchased the Engel padded insulation/transit protection bag/cover.
The bag is a verv good piece of kit and the top of it closes with velcro.
Now, because it is a pretty sloppy fit I found that was able to slide 30mm closed cell foam sheets into the air gap. On my freezer the front, back and end faces have the foam jammed into place and so effectively I thickened the freezer walls by 30mm and the 70 year old motor mechanic/ auto electrician in me figures the the foam must be a definate way of insulating the food.
The foam I used was cut from sheets i bought from Whitworths as item #31039 which is 1320mm x 325 x 30.
Its a tight fit but it is there! "there" being the operative word.
Even if your fridge/freezer available for it, and my old Waeco CF 18's didn't, simply use pvc cement to bond the 30mm panels to those faces, eg lid etc, which dont have condenser outlets etc.
On my old Waecos the wall thickness was way less than the 30mm addition I gave them.
Don't know why I forgot to mention it and why nobody else has. As i see it the foam weighs nothing, takes up vittle space and MUST save heaps of power. (though I've never measured the difference. For me it was the best $40 Ive ever spent)
Consuming 5 amps for every hour my TV is running I simply must minimise my freezer consumption.
Sorry it was a rant....
Brian.

I've a couple of Engel 40 ltr drop ins which I still need to add insulation in to but will in the coming months
So far am happy with them and the options of fridge freezer hoping will suit my needs

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southace said..

Yara said..
Loading up a freezer does not significantly change the power draw, provided what you put in is already frozen. What it does change is the cycle time- runs for longer, and off for longer.

If you want to reduce current/energy consumption, reducing the times the door is open, and adding insulation, is the way to go.

Won't the run time be reduced and the off time increase once I have my freezer full of frozen milk, icecream and Meat?

if my freezer is -15 on shore power for the next couple of months surly everything I put into will freeze with out having to freeze it first?

Exactly Ace. I try to keep my freezer full which means going to the supermarker about weekly. What I buy is never frozen, just meats and lasagnes etc out of the fridge. By next morning everything I put in the day before is down to c. -13 or so. When I measure I use an Infrared gun. (only ever temp tested a few times in the early days because the system works). I find that products like 'stuffed chicken (quinoa/cheese) roasts' definately do NOT keep like red meats or fish do. Er, error. I DO also buy Birdseye vegies etc which are still pretty frozen by the time I eventually back to the boat.

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southace said..
I might also connect a computer fan directed over the compressor wired into my solar. I have noticed a massive diference when I run the fridge computer fan or open the sink door where the fridge compressor located.

Thanks for the replys guys I will keep you posted how it goes.

Yes the extra fan, keeping the condensor cooler will help immensely. Almost no extra current draw. I took the fan out of my first Waeco and piggy backed it to the outside of the second Waeco as a suction device to assist the inner fans extraction thru the plastic grill.
How lucky you are to have shore power. I run my genny (running a Sterling 12/60 charger) for two hours per day.