Absorption vs Compressor 'fridge?

[booster]

Anyone with lithium batteries and experience will tell you you idling for charging them is not a normal routine if you have a second alternator.

Red highlight mine. This is what you said. It does not say you and it does not say anyone who has enough lithium to go three days and never goes over it. It says anyone with lithium with no disclaimer at all, and that is what I addressed in my reply. I did not limit it to your use and just referenced your last van and how much power you said you you used which would not quite make 3 days. If you can make it now fine, not everyone has your setup or use pattern, plain and simple.


We have sat for a week without moving, but are fairly low power users and we can run nearly that long on batteries, but the solar covers it almost all the time and did when we sat that long. Someone with higher use, less battery capacity be it lithium or not, and not enough solar would have to drive or idle. No choice at that point and if you don't drive all that is left is idling.

[ks@yvr]

I agree that 3-4 days is what we consider the ideal time at most locations. Generally if we stay longer somewhere then we tend to drive the van every 3-4 days somewhere to hike or sightsee.

We are almost always boondocking (rec sites or blm), so we carry a small tent with us to hold our spot with a couple of chairs, if we have to drive to the nearest general store or supermarket. We normally bike if possible. Our lithium batteries are usually fully charged in 3-4 hours and half charged in about an hour. We are electricity mizers and only have propane (1lb refillable [carry 3]) for the hot water boiler use regularly and an outdoor stove we use sometimes. We tend to use the induction cooker most days for cooking and the microwave infrequently but I like it for quickly reheating food. We turn on our inverter only for the induction cooker or microwave while camping. We do have some 120 V outlets besides the one for the induction cooker and microwave, inside and outside off the inverter but generally haven’t used them (nice to haves). Most of our devices charge off usb and we have a number of usb outlets. The refrigerator is our largest ongoing draw and our batteries have been lasting as needed between charging. In the last month on the road there was only one instance that we had to charge our batteries on ‘day 5’ but the rest of the time everything charged in the normal course of our travels. We can live with 200 ah of lithium and it works for us. Sure 300 ah or 400 would be nice but aren’t really required, space to add one or two more batteries is at a premium in my setup.

Sorry a little off topic but our largest energy draws are #1 the induction cooker and a long way behind #2 the compressor refrigerator that is very energy efficient. Our heater for the cooler months is a gasoline Webasto off the main van gas tank. Hot water is heated by a coolant loop off the engine or a 750 watt 120 V power off either the inverter or shore power and stays hot for about 36 hours. We tend to only use the engine coolant loop for our hot water needs.

Happy camping,

[booster]

I agree about the energy use always being necessary to address whenever the topic of compressor frigs comes up as there are so many different systems out there and many of them may not be able to handle the extra load without modification. Probably 1-4 days is most typical in class b use and may be on the low side of that, but are those that stay longer.



With more of the popular parks stating to look at shuttle service instead of driving we may see more longer stays and less driving even on shorter stays. We thought the shuttle setup at Zion was fantastic when we were there a few years ago as you can even get to town on it, but was also close enough to walk to. We rode the shuttle to different hiking spots the whole time and didn't need to drive as they had bathrooms so tanks OK and could get food groceries without driving even.


At places without shore power, like Zion, a drive less model makes the compressor frig thing more difficult for sure.

[avanti]

Originally Posted by Davydd

the Isotherm refrigerator is proving way more efficient that my previous Nova Kool.

Have you (or ARV) concluded that the Isotherms are in some way superior to the NovaKools, or is it just that the size of your particular model suited your design?

I am pretty sure they use the same Danfoss compressors, so the apples-to-apples efficiency is probably pretty close, although obviously your current much-smaller unit will consume less power.

Is there any reason I should prefer an Isotherm in my next van?

[GeorgeRa]

Originally Posted by Davydd

……………………….
Propane adds weight and space where batteries could be of better use or in my case since batteries are inside the van now I get more fresh, gray and black tank capacity than any other 2500 short Sprinter van on the road that I am aware of. Onan generators add weight and especially space in otherwise better use of that space. I’ve had vans with Onan generators, wet-cell lead-acid and AGMs. I would never go back. I also desired to go non-dually and could not do all that without lithium ion batteries. I still wanted a Class B van where I didn’t have to take a shower or poop and pee in the living space. I also didn’t want a van where you had to make either/or conversion of space decision of sleeping or staying up.

20lb. LPG tank contains 125kWh of energy, that is total weight of 37lb. including the tank. So, in 12V world over 10kAh energy source weighs 37lb. rechargeable in 10min.
10kWh Renogy battery would weight 270lbs. and required hours to recharge.
Which energy source or battery buffer is heavier?

I appreciate your passion for lithium and ARV, but have hard time seeing your extrapolation of your passion or needs to many other having different experience and needs including myself.

An example, for me 360-degree view is an absolute must, trading convenience of dedicated beds or shower for windows or living space. I would not get any camper van cage like architecture.

Solar power energy source (it is a source not a buffer) is an absolute need for extended stay without a need to fire a generator nor the engine.

Different strokes for different folks, I understand why you don’t like solar power, and hopefully you will understand why other folks like solar power or 360-degree view.

[booster]

Originally Posted by avanti

Have you (or ARV) concluded that the Isotherms are in some way superior to the NovaKools, or is it just that the size of your particular model suited your design?

I am pretty sure they use the same Danfoss compressors, so the apples-to-apples efficiency is probably pretty close, although obviously your current much-smaller unit will consume less power.

Is there any reason I should prefer an Isotherm in my next van?

Not davydd, but I think based on what the design looks like to me I think the condenser and fan configuration would probably be any real difference. No comparison test data as I have never had a Novakool.



Especially if you seal the air bypasses around the fan at the compressor and also in fresh air feed to prevent any looping, the Isotherm setup makes the condenser coils and the compressor see 100% of the fresh air going through the fan so no relying on gravity to assure condenser cooling without extra fans. The compressor and coils on the new frig barely get warm, especially at the lower compressor speeds, probably no more that 20-30* above ambient which is very cool for a compressor from what I have seen.


The Novakool probably would do very well if the condenser and compressor were boxed in and fed only fresh air over both in a well distributed way as there is a lot of room for air around the coils.



The condenser/compressor module in the Isotherm appears to be a Danfoss designed unit sold as an assembly so they probably have knowledge to be able to do a very design, if they tried hard that is which is not guaranteed.


My last test the showed under 300 watt hours per day is really quite low energy use, especially with no cold plate involved.

[booster]

One thing that I don't think we have ever asked those the switched to compressor frigs and would never go back to absorption (that would describe us).


Ponder this question:


"If a propane powered frig got rid of the temperature handling issues and out of level stuff would you still prefer the compressor frig?"


Personally, if such a frig was available I would likely choose the propane as it just makes sense if you take out the disqualifying problems they currently have.

[avanti]

Originally Posted by booster

"If a propane powered frig got rid of the temperature handling issues and out of level stuff would you still prefer the compressor frig?"

Well, if we are allowed to choose unobtanium, I would run propane through a fuel-cell and keep the compressor.

[GeorgeRa]

Originally Posted by booster

One thing that I don't think we have ever asked those the switched to compressor frigs and would never go back to absorption (that would describe us).


Ponder this question:


"If a propane powered frig got rid of the temperature handling issues and out of level stuff would you still prefer the compressor frig?"


Personally, if such a frig was available I would likely choose the propane as it just makes sense if you take out the disqualifying problems they currently have.

For me the key compressor fridge attribute is no need for levelling. If this issue would be solved for propane fridge it would be my likely choice. I recently gave to my son my old Dometic portable absorption fridge, still running like new, some bruises from heavy use, it was purchased in 1978.

[booster]

Originally Posted by GeorgeRa

For me the key compressor fridge attribute is no need for levelling. If this issue would be solved for propane fridge it would be my likely choice. I recently gave to my son my old Dometic portable absorption fridge, still running like new, some bruises from heavy use, it was purchased in 1978.

Stationery gas frigs were very durable back in the day. My grandmother had one in her house the was about 40 years old and still running, but boy was her kitchen hot and the wall behind it stained as it had no exhaust.

[Davydd]

I was just checking my Isotherm Freeline 115 manual compressor refrigerator. Just for kicks it said the compressor could be damaged if it was 30º out of level. I don’t think you can park, stand and sleep in those conditions.

[hbn7hj]

Originally Posted by avanti

Well, if we are allowed to choose unobtanium, I would run propane through a fuel-cell and keep the compressor.

Our propane fuel cell still hasn’t shown up in the for sale mode.

[Renwick]

Originally Posted by Kegan

The Dometic refrigerator in my 2008 RT Popular 210 finally gave up the ghost. Now onto a new refrigerator. Absorption v. Compressor?

FYI, in the year or so we've owned this RT, I have never found the need to use propane. Couple of other considerations:

• We do not boondock.
• We do like cold food.
• In particular I would like the freezer to work well as I have a close relationship with ice cream
• My experience has been erratic with food keeping cool as we drive (which may have been an indicator of a dying 'fridge or perhaps user error).
• Absorption is reportedly better at staying consistently cool (less sensitive to level ground, etc)
• Compressor units are a bit less expensive, but I don't mind spending the $$ for something that works better.
• Preference is for not having to reconfigure the counter/slide in area/electrical to accommodate the new unit.

Thoughts, opinions, experiences, rants or raves? Thanks in advance.....

I replaced the fridge on my ‘95 roadtrek popular with compressor Truck Fridge cost around $800 bit pricey. I been running 24/7 I had 2 100 watts solar panels on roof and 2 125 ah AGM batteries. Not worried leveling the van.

[Kegan]

Originally Posted by bwatters60

Another vote for the compressor fridge since I replaced our 3-way RM2554 with a Nova Kool R5810 three years ago (2008 RT 210P). Faster cooling, no need to be level, more consistent temps, and no battery issues. See attached.

Thanks for this info. I'm getting ready get the R5810 and they surprised me with a 20 week back order. Ouch. Still checking distributors in case I can find one in stock from a cancelled order or whatever.

[Renwick]

I bought my TF 130 Truckfridge Georgetown, KY 40324
Ph 502-863-0473
The size of this model
H-29 1/4
W-20 1/4
D-20”

[Renwick]

Kegan,
Correction the ph 502-863-0373
Sorry

[Kegan]

Originally Posted by bwatters60

Another vote for the compressor fridge since I replaced our 3-way RM2554 with a Nova Kool R5810 three years ago (2008 RT 210P). Faster cooling, no need to be level, more consistent temps, and no battery issues. See attached.

Bruce - Just wanted to send a quick thank you for your information, and in particular the photos you had in your earlier attachment. I was able to source a R5810 (found a dealer who had a couple in stock), which was surprising since the factory and a few of the other dealers said it was a 20 week backorder. Hoping to get it here by next week. Cheers.

[bwatters60]

Originally Posted by Kegan

Bruce - Just wanted to send a quick thank you for your information, and in particular the photos you had in your earlier attachment. I was able to source a R5810 (found a dealer who had a couple in stock), which was surprising since the factory and a few of the other dealers said it was a 20 week backorder. Hoping to get it here by next week. Cheers.

Thanks! I should add that since creating the pdf, I have reinstalled my fans behind our NovaKool. I live in TX and I have family in FL, and so I spend a considerable amount of time traveling/camping in the south in hot, hot weather. This summer I reinstalled the rear fans (with a manual switch) and found that they really help the NovaKool keep lower, and more consistent lower temps in high temps (95+). We still have to monitor the fridge temps and make periodic thermostat adjustments, but overall we are still very happy we replaced our 3-way with a compressor fridge. Good luck!