12/120V Portable Refrigerator/ Freezers

[chuck]

Dometic CF-35 Refrigerator/Freezer
The original intent of this post has been changed and taken over by other ideas. Therefore, I have removed the original post with its questions.
Chuck

[kmclemore]

Chuck, I doubt if anyone is going to be able to tell you the specific current drain or duty cycle because this is highly dependent on the ambient temperature in which you'll be using it, how well you've insulated it from heat and how well you ventilate the unit for cooling. The best you could hope for, IMHO, is for someone who has one to tell you what sort of performance they get, but even there your performance is likely to vary significantly.

[chuck]

Chuck, I doubt if anyone is going to be able to tell you the specific current drain or duty cycle because this is highly dependent on the ambient temperature in which you'll be using it, how well you've insulated it from heat and how well you ventilate the unit for cooling. The best you could hope for, IMHO, is for someone who has one to tell you what sort of performance they get, but even there your performance is likely to vary significantly.

Thanks for your input. Due to the things you mentioned is why I gave my amfient temperature as 70* F and asked questions 5 and 6.

Thanks--Chuck

[Russ]

I have the Edgestar 48q model. Similar in that I think they both use the same compressor.
We keep it at 34-36F which makes everything nice and cold but not frozen. Actually, if we put frozen stuff in there, they stay frozen for long time, we just don't like to drink our water as a solid.

It runs about 30-40% of the time with ambient temps in the 80s during the day. We have an 80w solar panel that does a real good job of keeping the thing going for several days. Mixed in with that 12v usages is VHF, LED cabin lights and water pumps (fresh water and washdown). YMMV

I have a single deep cycle battery used for the "house" and a dedicated starting battery. Works very well. Love that fridge.

Another factor is how often you open the lid. Once cold and all internal stuffs are stabilized to the set temp, it will keep for a while. We open the lid often and replace cold bottles of water with room temp bottles. So it works harder to cool stuff down.

Setting it to ZERO F will dramatically increase power I would expect. Never had a desire to go that low. Testing it on "fast freeze" mode it went that low but ran for quite a while to get there.

[Max Entropy]

Chuck, I doubt if anyone is going to be able to tell you the specific current drain or duty cycle because this is highly dependent on the ambient temperature in which you'll be using it, how well you've insulated it from heat and how well you ventilate the unit for cooling. The best you could hope for, IMHO, is for someone who has one to tell you what sort of performance they get, but even there your performance is likely to vary significantly.

Thanks for your input. Due to the things you mentioned is why I gave my amfient temperature as 70* F and asked questions 5 and 6.

Thanks--Chuck

Hi Chuck - I have an old no-name, probably Chinese, one about the same size as yours, maybe a bit larger that, I picked up 2nd hand. There are possibly a few other variables - how much power does the panel really put out over 24 hrs, how full is the fridge, and what is the thermal capacity of the contents, and the R-factor of the insulation etc. For example if the freezer was full of ice then it would stay cold a lot longer than if it was empty or full of bread - that's because the thermal capacity of ice is huge compared to bread, or air for that matter. Thermal capacity is basically how much energy it takes to change the temperature of a given mass of material one degree (without reference to specific system of units). So - one thing I did before a cruise was to pre-freeze some ice in the home freezer in a wine bag and stick that in the boat fridge when provisioning. Wine bag doesn't leak so you can either toss it out (the water!) when melted or use it for extra fresh water. The fridge wd use about 30-40 watts on startup, and then after stabilising come on briefly once an hour or so at lower power. I ran everything including engine starter off 1 AGM battery and ran the engine no more than 4 hrs/day for propulsion and charging, with really no problems, though I'm not recommending you try that. But this was in the Pacific Northwest, and maybe you get more solar and higher tmeperatures where you are. If you have the space I would recommend that you build an insulated box for it because that's the best way to reduce power consumption.

[RobertB]

I have the CF-50. I also purchased the accessory insulating blanket. Running on a single battery can be challenging, running on two much easier. I recently discovered not to set the voltage cutoff threshold to high, better to set to low. If you find the unit cycling on and off real quickly, it is most likely it has hit this threshold. I keep mine at 32 degrees.

[DaveB]

Chuck,
Have a 63 quart Edgestar for 3-1/2 years.
Go to top of page and click on Forum, than Advance search.
Under Search for Key words, type: Edgestar, under search for auther type, DaveB
You will find 4 pages dated back to 2010, start with page 4 and than 3-2-1 to current.
Click on a post of interest and will take you to the postings.
Lot of good stuff you need to know.
Dave

[chuck]

It runs about 30-40% of the time with ambient temps in the 80s during the day. We have an 80w solar panel that does a real good job of keeping the thing going for several days. Mixed in with that 12v usages is VHF, LED cabin lights and water pumps (fresh water and washdown). YMMV
.

Russ,
Thanks for the info. As I stated, my ambient will be around 70 during the day. Will keep mine set at 38. at that setting it holds at 37. The 30 to 40% is good data. I will have a 55 hooked parellel to a 20 watt panel. Do not plan on setting to 0 *F, was just wondering.

Thanks--Chuck


Quote from Max
{ I ran everything including engine starter off 1 AGM battery and ran the engine no more than 4 hrs/day for propulsion and charging, with really no problems, though I'm not recommending you try that. But this was in the Pacific Northwest, and maybe you get more solar and higher tmeperatures where you are.}

Max,
Thanks for reply. I am talking about Pacific NW in the San Juans. I was talking about getting 24 AH from the solar cells out in the sun all day.

Take care--Chuck

[chuck]

I have the CF-50. I also purchased the accessory insulating blanket. Running on a single battery can be challenging, running on two much easier. I recently discovered not to set the voltage cutoff threshold to high, better to set to low. If you find the unit cycling on and off real quickly, it is most likely it has hit this threshold. I keep mine at 32 degrees.

Robert,
Good info. I will set my VCO on low also. I thought I would try a movers protection blanket from Harbor Freight as an insulating blanket.

Thanks---Chuck

[bartmac]

Having setup a 200 W solar panel system and 2 x 183Ah gel battery system to run our 45L Vitrifrigo fridge (3.5-4.5A draw) I can report that solar panels on a boat do not produce the amount of juice due to a number of factors....shading from sails,heeling,limited optimum mounting spots etc.....so I tried to evaluate the run cycle....very high ambients ie 30-35C and the need to open the unit regularly certainly had an effect.So found the following....no fan forcing in the fridge means the packing of a small fridge causes thermostat lag...so fitted small computer fan both our camper and Mac fridge and also our Waeco 35L(used as a freezer mostly)....huge improvement to the temperature...evens out the fluctuations...probably uses more power but actually cools things much more rapidly.Also bought dedicated plastic containers of a standardised size with lid lips...creating air space between the containers thus allowing airflow.The use of larger plastic boxes allowing the removal and replacement of a batch of things (ie salad/veges etc,small goods ie cheese,lunch meats etc) from the fridge...shorter door opening and rapid replacement.The up shot of all off this was that a theoretical 200w system and a 5-5.5hour effective sun time should make approaching 1Kw......it clearly does NOT...so we have to look for another way to make electrickier or use less
Next I'll rewire the solar reg to show both watts in and out

[Seapup]

I have the dometic cf50 also, its basically identical to the 35 but taller. I used a kill a watt meter (about $20 online ) To get a general idea of power consumption for it, but that was awile back and I cant really remember exactly what it used. I think it was like 60w~4.5A on normal and 100w on turbo. If it was not too hot outside the meter showed it ran about 10-15 min an hour and closer to 30 minutes in the heat of summer. I throw it on turbo and full cold sometimes when we are motoring a long ways and then it wont have to kick on for a few hours after we stop. I leave the meter on the ac cord for the fridge for when the boat is left at the dock, but don't really check it much. Basically we found we motor about an hour a day when cruising and our 40A alternator is enough to keep the batteries topped off. Its been a good little fridge, bought it used and are leaving it run pretty much year round.

[Russ]

Solar is tricky. As mentioned, it's not 100% efficient. It only is in direct sun at 90 degree angle to the sun. That's why so many are mounted or track the sun via motors.

Summers here are bright (little atmosphere) and long (high latitude) in the summer. You have to have reasonable expectations of direct sunlight and charging conditions. Google this to get more info on solar and what to expect.

Our 80W panel will keep up with the fridge, but it does drain the battery down each day. Probably not a good idea to leave it on 7 days a week. So, I'm installing a 12v timer that will run the fridge 3 hours a day while we are away. Should keep it somewhat cool until we get up to the marina. Our marina has no power so our boat runs "off the grid".

[Max Entropy]

I have the dometic cf50 also, its basically identical to the 35 but taller. I used a kill a watt meter (about $20 online )[img]https://encrypted-tbn3.gstatic.com/images?
...

That little device or knock-offs like it should also be able to tell you the total kWh used over a period of time, which will give you a pretty good idea what you'll need on a trip, and whether your power source will be up to the job. You can experiment by setting the fridge at different temperatures to see how to optimise performance.

[DaveB]

Russ,
I run my 63 quart Edgestar now with a 75 watt inverter on AC plug as my DC cord failed about 2 years ago. It isn't effeciant as DC and uses more power but works good with my 2-29 amp house batteries and twin 40 watt solar panels on top of Bimini, full direct sun .
I tried hot conections on dc line (cut off dc plug many have failed) and got no response.
I only need solar power if on hook or beached more than 3 days.
That's at 85 degrees or more during day, if battery is below 12.2 volts I shut refig off for night and temps are below 45 degrees in morning and turn it back on.
Only did this once to see how low temps got in frig.
Those in higher latitude may want to turn off frig. at night.
I don't need solar panels if anchored 3 days or less and voltage never gets below 12.3 volts.
Since I have them and Know I am going to be beached or anchor more than 2 days I use them.
One of these days I am going to hot wire the DC outlet.Until than using a 75 watt inverter cig. plug.
Dave

Solar is tricky. As mentioned, it's not 100% efficient. It only is in direct sun at 90 degree angle to the sun. That's why so many are mounted or track the sun via motors.

Summers here are bright (little atmosphere) and long (high latitude) in the summer. You have to have reasonable expectations of direct sunlight and charging conditions. Google this to get more info on solar and what to expect.

Our 80W panel will keep up with the fridge, but it does drain the battery down each day. Probably not a good idea to leave it on 7 days a week. So, I'm installing a 12v timer that will run the fridge 3 hours a day while we are away. Should keep it somewhat cool until we get up to the marina. Our marina has no power so our boat runs "off the grid".

[Russ]

Russ,
I run my 63 quart Edgestar now with a 75 watt inverter on AC plug as my DC cord failed about 2 years ago. It isn't effeciant as DC and uses more power but works good with my 2-29 amp house batteries and twin 40 watt solar panels on top of Bimini, full direct sun .
I tried hot conections on dc line (cut off dc plug many have failed) and got no response.
I only need solar power if on hook or beached more than 3 days.
That's at 85 degrees or more during day, if battery is below 12.2 volts I shut refig off for night and temps are below 45 degrees in morning and turn it back on.
Only did this once to see how low temps got in frig.
Those in higher latitude may want to turn off frig. at night.
I don't need solar panels if anchored 3 days or less and voltage never gets below 12.3 volts.
Since I have them and Know I am going to be beached or anchor more than 2 days I use them.
One of these days I am going to hot wire the DC outlet.Until than using a 75 watt inverter cig. plug.
Dave

Dave, I think you, Sumner and I bought the same Edgestar freezer at the same time they had that great deal on them with free shipping.
Mine's worked great. I did recently take the cover off to blow the dust off the condenser. I saw another fan not moving. Then realized it's the AC power supply. I believe the AC supply drops the voltage down to the native 12v it runs on. Using an inverter you are raising the voltage to 110 just to drop it back to 12v. You should try to hotwire your because I'm sure it's not as efficient.
I'm going to try an experiment and run my fridge off my 75w inverter then off native 12v to see how much amperage it draws with each.

We keep the boat in a slip and when we get onboard, the box is warm. So my idea was to put a timer on it and run it a few hours a day in the morning. If we go sailing, we'll arrive to a cold box. Otherwise it hibernates another day waiting for the owners to return. Just got the timer, now to hook it up.


--Russ