Refrigerator solution while on the road

[Glenn Baglo]

Keeping in mind that if you choose to ignore a certain forum member, you will get alerts that that member has posted and that you are ignoring them. You will also see responses to whatever was posted. So, good luck with that.

[sokhapkin]

To my experience "ignore this thread" is the best solution. I frequently use it for rallies-related threads I'm not going to participate in.

[gordon2]

Originally Posted by Glenn Baglo

Keeping in mind that if you choose to ignore a certain forum member, you will get alerts that that member has posted and that you are ignoring them. You will also see responses to whatever was posted. So, good luck with that.

Well there has to be a way to ignore the alerts also!

But (for me at least), the notice that you see in the thread:

This message is hidden because USERNAME is on your ignore list.

would always make me so curious that I would have to un-ignore the user and see what he or she said.

But its a fun idea and got us off the dead horse for awhile.

[alan H]

You know what that say about options

There are like a..holes
And everybody has one
👍



Sent from my iPhone using Fiberglass RV

[Glenn Baglo]

I tried ignore poster when a commercial member used every opportunity to have his logo published in every thread. It was a free ad for him. I gave up because it aggravated me to be told I was ignoring him every time he posted.

[SilverGhost]

I have a 12v compressor fridge and my dad has a 3 way fridge. In light of this thread I asked him what he does. Turns out his Dometic will shut off when he goes over 35mph if the fridge is left on propane. So he switches to 12v when they leave camp, then back to propane if they stop for a while or 120V when they arrive at camp.

Right now the circuit board has fail several times (one under warranty, at least one that Dometic paid part only). We were talking and if it fails again he's giving serious thought to a 12V compressor fridge. Less money on filling up propane and he already wants to do solar.

Jason

[TomandCallie]

At risk of getting slightly off topic...can you tell me what a "compressor fridge" is and just how it differs from a 3-way? I intend to run my 3-way just like your dad is doing now. Did Dometic indicate that the board was failing because of using the 12V to travel?

[Darwin Maring]

A compressor fridge has a small compressor that runs off of 120VAC. It does not run off of propane or 12 VDC. They are not expensive and they cool very well.

Now, Someonw will pipe up and say there are some 12VDC units and that you can run your 120VAC off an inverter and they will be correct but get your wallet out for the extra expense.

There are also 12VAC Coolers that will cool, freeze and even warm depending on their settings. They are solid state as in no moving parts, no heat strip, no chemicals. Go to Camping World web site for a lookup.

[redbarron55]

I don't know about the others, but not
My Norcold 704DE has a 21 volt AC Swing compressor that runs either from a 12 volt inverter built in or a 21 volt winding off the built in 120 vac transformer shared with the inverter.
The inverter has to generate a 60 hz. Square wave for the compressor to work correctly.
It will also run from the 120 vac when operated off an inverter.
The beauty of the swing compressor is no starting surge unlike a rotary compressor.
Engle fridges are also made this way.
The fridges with Danfoss compressors are quieter since the piston I'd not rattling back and forth.
Both seem to draw about 40 watts running.
My Norcold 704DE averages about 20 watts taking into account cycle time.
If you go with a dorm type of refrigerator you will need a little larger inverter to account for that starting surge.


Sent from my SCH-I605 using Fiberglass RV mobile app

[Darwin Maring]

Red Baron: that is one sweet fridge. Wish I had one.

[redbarron55]

The Norcold is OLD and I bought it from a boat dealer who had pulled it out for $25.00.
The DC inverter was running at the wrong frwquency (50 hz instead of 60).
It cooled OK on 120 volts, but not well on 12.
Being an electronic type I searched for and found a schematic and retuned it to where it put out 60 hz and it will cool quite well now.
It will freeze a diet coke and put a slush in a really cold beer!
I added more insulation in the cabinet I built and I put some thin aluminum tape on the cooling coils along with a small computer fan that runs along with the 12 vdc inverter to improve the efficiency.
It makes a fairly loud 60 hz buzz when it's running, but not too bad in the cabinet with the extra insulation.
It works for us!

[SilverGhost]

Originally Posted by Darwin Maring

A compressor fridge has a small compressor that runs off of 120VAC. It does not run off of propane or 12 VDC. They are not expensive and they cool very well.

Now, Someonw will pipe up and say there are some 12VDC units and that you can run your 120VAC off an inverter and they will be correct but get your wallet out for the extra expense.

There are also 12VAC Coolers that will cool, freeze and even warm depending on their settings. They are solid state as in no moving parts, no heat strip, no chemicals. Go to Camping World web site for a lookup.

You are right - I have a 12V Norcool that runs off my battery and solar setup. And to the best of my knowledge (and without tearing it apart to prove it) there is a 12V compressor and no 120V inverter. I do understand that they are much more expensive than the small 120V dorm fridges. Don't know how they compare to 3-way fridges $$.

Jason

[Carol H]

Originally Posted by SilverGhost

You are right - I have a 12V Norcool that runs off my battery and solar setup. And to the best of my knowledge (and without tearing it apart to prove it) there is a 12V compressor and no 120V inverter. I do understand that they are much more expensive than the small 120V dorm fridges. Don't know how they compare to 3-way fridges $$.

Jason

Keep in mind when comparing costs of fridges you also need to look at the cost of the additional equipment - such as solar or generator that are required to run a any fridge on 12V vs simple running one on propane.

[David Tilston]

I passed on a 12VDC compressor fridge in the wreckers. They only wanted $25 for it. Ah, regrets.

Depending on the fridge, 60W, or so, of solar is all you need. Plugging in would work too.

On a three way, the 12 VDC heater may consume around 150W, or more then 10A. Using a 100AH battery, that gives you less then 10hrs. But as long as you can get 10A from your tow vehicle to the the trailer, you should be fine on 12VDC. Your alternator will hardly notice it.

[redbarron55]

Types of refrigerators
1 120 vac compressor "home or dorm type.
Rotary compressor uses household current. The small "dorm" type of refrigerators might be usable with an inverter, but the starting surge will require more than a 300 watt rating. While the running power is also around 40 watts like the Swing compressors they do have that surge to get the compressor turning.
2. 12 volt compressor runs of 12 volt dc this is probably a rotary compressor . It could run on 120 vac with a power supply either built in or separate.
3. 12 volt Peltier junction which used DC current to "move heat from one side of the junction to the other. These are those coolers that will heat or cool depending ont eh polarity of the current. These will build a temperature difference of 30 - 40 degrees F.
They often have a power supply for 120 vac as an option. They cool but in hot waether not very much.
4. Swing compressors do not rotate, but rather oscillate from one direction to the other compressing the refrigerant gas with pistons built into a solenoid. Most operate on about 22 volts alternating current.
The 12 volt DC is switched from one polarity to the other by a transistorized oscillator to generate the 22 volts at 60 Hz.
They may or may not have a tap on the oscillator transformer for 120 volt ac input from this source as well as from the 12 volt dc source.
The Norcold 704 DE and the Engle units are this type. These units have no starting surge and draw an=bout 40 watts running and the average is less.

Lastly there are the absorption tyoe that depend on heat to drive the compressor cycle. The only difference in the LP, 12 volt, and 120 volt or any combination is the source of the heat. The LP gas flame, the 12 or 120 volt current with a resistance element.
The amount of heat required i the same power level if it generate the same amount of cooling.
the current required from 12 volt DC is 10 times the current required on 120 volts AC. (roughly).
Then you could use ice in an ice box for a little cooling as well.
My Norcold 704DE keeps everything in it very cold or as cold as I turn the thermostat. My Norcold 1200LRIM keeps the food just cold enough for me to not yet toss it out.
I have added fans etc to improve the cooling and everything I can think of, but it is marginal.
Those are the choices

[SilverGhost]

Originally Posted by Carol H

Keep in mind when comparing costs of fridges you also need to look at the cost of the additional equipment - such as solar or generator that are required to run a any fridge on 12V vs simple running one on propane.

Hmm, mine runs about 3 days on a fully charged group 24. I'd guess if I upgrade to group 27 or go to 6V Trojans that could be substantially longer. A <$100 solar panel keeps enough charge to run indefinitely.

For me the additional cost is propane - I don't have it. I would need the tank(s), brackets, covers, regulators, hoses, pipes, safety valves, etc. to be installed. I admit it's on the wish list, but not in the budget.

And how many days can you run a 3 way fridge on propane? A week? Month? I assume it depends on size of fridge and how often you open it.

I weighed the pros and cons for both before I purchased, and this option works for me. Only regret is not having a larger model.

Jason

[Carol H]

Originally Posted by SilverGhost

Hmm, mine runs about 3 days on a fully charged group 24. I'd guess if I upgrade to group 27 or go to 6V Trojans that could be substantially longer. A <$100 solar panel keeps enough charge to run indefinitely.

For me the additional cost is propane - I don't have it. I would need the tank(s), brackets, covers, regulators, hoses, pipes, safety valves, etc. to be installed. I admit it's on the wish list, but not in the budget.

And how many days can you run a 3 way fridge on propane? A week? Month? I assume it depends on size of fridge and how often you open it.



Jason

I think you would be surprised as to just how many days you can run a fridge on a single 20lb propane tank.

In my experience running the fridge around the clock on propane its surprisingly efficient. I can't say for sure as to how long it might go only running the fridge around the clock as I have never simple run just the fridge on propane.

I also use propane to run the hot water tank daily, as will as the stove top a couple of times a day and occasion oven use (perhaps once every 6 days out), in addition to the furnace as needed. I have camped out for 45 days straight with about 70% of those days off the grid (even when on the grid I am still using propane for everything but the fridge) without needing to refill a 20lb tank - even then the tank was not completely empty.

As many people already have other appliances they use daily on propane they will already have the tanks so no added purchase cost there. So the only added operating cost is the propane being consumed by the fridge which I suspect based on my experience is a relatively small volume for most of the small fridges many of our trailers have.

In my experience camping with friends who have newer 12V only fridges they can get by for max of a couple of days assuming they are needing to use their lights and water pump and furnace etc before they need to set out a 100 watt or greater panel assuming there is sunshine. If no sunshine then they need to pull out the generator.... in these parts due to more often than not heavy tree coverage make the solar less than optima, the later happens frequently as it does in late fall or early spring camping when there is a shortage of sunshine ... all of which has a cost associated with it.

I also have solar BTW ;-) was simple pointing out that when doing price comparisons for various fridge power type chooses one needs to add up all the costs associated with each choose/system.