Replacing fridge with thermoelectric cooler

[The Eyesore]

Our Dometic RM2310 just died. Waaah!! We're going on a two-week trip in October. I'm thinking of replacing it with a thermoelectric cooler. I don't want the noise of a compressor and don't want the expense of another absorption fridge (although I did love ours before it died).

Looking at this one:
https://www.amazon.com/Koolatron-P27.../dp/B0001MQ7DQ

It seems it will fit into the void of the dometic after I pull it out, and it's operable upright, so the door will swing out like a fridge. Any suggestions or opinions welcome.

[jrobe]

Read the 20% 1 star reviews on that cooler and then decide if that is really what you want. You can't even put ice in there in the upright position which may be how it works the best.

I have no idea what the concern is about the "noise of a compressor refrigerator." Ours is very quiet, keeps food perfectly cold and takes very little battery power. It is close to perfect for our RV.

[avanti]

Peltier devices are significantly less energy efficient than compressor units--more so as the heating load increases. If this matters to you, it wouldn't be a great choice as a permanent solution. They are nice and quiet, though.

[RT-NY]

Originally Posted by The Eyesore

Our Dometic RM2310 just died. Waaah!! We're going on a two-week trip in October. I'm thinking of replacing it with a thermoelectric cooler. I don't want the noise of a compressor...

Originally Posted by jrobe

I have no idea what the concern is about the "noise of a compressor refrigerator." Ours is very quiet, keeps food perfectly cold and takes very little battery power.

I agree with the OP about the noise of a compresser -- so much so that I am surprised that I have never seen it come up before in discussions about compressor vs. absorption. This is a matter of personal sensitivity, of course, but I often find the humming of a fridge in an RV very annoying.

And for me the 60+ amps a day that even the best compressors require is not "very little battery power."

So a 3-way fridge will always work better for me even given its limitations, but there is no "right answer" on this question -- it all depends on what you like and what you need.

In any case, I would not be surprised if the thermoelectric cooler is not very satisfactory and it seems to require as much power as a compressor.

[booster]

Originally Posted by RT-NY

I agree with the OP about the noise of a compresser -- so much so that I am surprised that I have never seen it come up before in discussions about compressor vs. absorption. This is a matter of personal sensitivity, of course, but I often find the humming of a fridge in an RV very annoying.

And for me the 60+ amps a day that even the best compressors require is not "very little battery power."

So a 3-way fridge will always work better for me even given its limitations, but there is no "right answer" on this question -- it all depends on what you like and what you need.

In any case, I would not be surprised if the thermoelectric cooler is not very satisfactory and it seems to require as much power as a compressor.

60 amp hours a day is on the high end for most 3cf or so compressor frigs. We run closer to 25-30 in moderate weather and would only get near 60ah per day in over 100* weather. A compressor frig of the size of the one the OP listed would use well under our use, especially is it was on a slide to get out food instead of facing horizontally.


Some have mentioned loudness for compressor frigs, but most are not bothered. Much quieter than the ceiling fan for instance or a circulating fan in the van, but to each their own.


The biggest issue with the OP listed on would be the 40* under ambient best case cooling which really isn't good enough for most of us.

[RT-NY]

Originally Posted by booster

60 amp hours a day is on the high end for most 3cf or so compressor frigs. We run closer to 25-30 in moderate weather and would only get near 60ah per day in over 100* weather. A compressor frig of the size of the one the OP listed would use well under our use, especially is it was on a slide to get out food instead of facing horizontally.

You are saying that a compressor fridge in moderate summer weather can run for 24 hours consuming only 25 amps? I do not know from personal experience, but my impression from what I have read, including on this forum, was that most people require more power than that. I am curious what other forum members experience with their compressors over 24 hours in, say, average summer days with 80 degree high temps?

[booster]

Originally Posted by RT-NY

You are saying that a compressor fridge in moderate summer weather can run for 24 hours consuming only 25 amps? I do not know from personal experience, but my impression from what I have read, including on this forum, was that most people require more power than that. I am curious what other forum members experience with their compressors over 24 hours in, say, average summer days with 80 degree high temps?

Yes we can, and do run lower than the 60 in 80*. Depending on humidity and how often we open the frig. Ours is an 85L, 3.1cf isotherm.

I have a thread on the initial setup and testing of it get the good performance we have achieved. It took a bit of work to get to the sweet spot as Isotherm had made some not all the great changes to unit compared to our previous frig of the same model.

We do see others that run higher than we do and that could be installation variations, insulating around the frig, etc or what temp the run frig at, plus use patterns. I would 60ah per day on the higher end of most users.

[GeorgeRa]

Originally Posted by booster

Yes we can, and do run lower than the 60 in 80*. Depending on humidity and how often we open the frig. Ours is an 85L, 3.1cf isotherm.

I have a thread on the initial setup and testing of it get the good performance we have achieved. It took a bit of work to get to the sweet spot as Isotherm had made some not all the great changes to unit compared to our previous frig of the same model.

We do see others that run higher than we do and that could be installation variations, insulating around the frig, etc or what temp the run frig at, plus use patterns. I would 60ah per day on the higher end of most users.

I have the same fridge, Isotherm 3.1 CF and the same energy usage.

Following your point mine also uses energy measured in amphours not amps, amps are units for current not energy, for example a car speed is measured in miles/hour not in gallons of gas.

It has to be very quiet to be able to hear the fridge.

[booster]

For reference on energy use on compressor frig.


https://www.classbforum.com/forums/f...lts-12476.html


and


https://www.classbforum.com/forums/f...lts-12869.html

[RT-NY]

Originally Posted by GeorgeRa

I have the same fridge, Isotherm 3.1 CF and the same energy usage.

Following your point mine also uses energy measured in amphours not amps, amps are units for current not energy.

Yes, of course, ah not amps - but the actual question remains: what is "the same energy usage" that you experience on average summer usage: 25ah for 24 hours?

Or, more to the point, what kind of energy budget should an average user of a compresser plan for for a 24 hour period. Is 60ah really that far off as a rule of thumb for most people?

[GeorgeRa]

Originally Posted by RT-NY

Yes, of course, ah not amps - but the actual question remains: what is "the same energy usage" that you experience on average summer usage: 25ah for 24 hours?

Or, more to the point, what kind of energy budget should an average user of a compresser plan for for a 24 hour period. Is 60ah really that far off as a rule of thumb for most people?

Energy usage depends on fridge size, van insulation, ambient temperature, type of compressor, 1 or 2 compressors, and fridge manufacturer. I can only reference to my Isotherm/Danfoss fridge. I had a similar size compressor fridge on the boat but it was not near as efficient as my Isotherm but it was not an expensive fridge, not Danfoss.

[booster]

Originally Posted by RT-NY

Yes, of course, ah not amps - but the actual question remains: what is "the same energy usage" that you experience on average summer usage: 25ah for 24 hours?

Or, more to the point, what kind of energy budget should an average user of a compresser plan for for a 24 hour period. Is 60ah really that far off as a rule of thumb for most people?

Our testing in the linked threads shows actual numbers and conditions.

As mentioned, it all depends on the frig size and quality of the installation on top of the frig brand and model. 60ah per day may fit some, others could easily target 30-40 overall average in moderate to warm temps. We have used 40ah per day for all the time we have had compressor frigs but it really is only been used for sizing battery banks and/or days with crummy solar conditions. We now have much more battery bank than we did in the beginning so no longer any need to even check it during use except as a curiosity.

We did such curiosity testing recently just to see if the oft quoted "no need for solar" was really that cut and dried with a big battery bank and big alternator when running a compressor frig. We run the lithium bank between 35 and 80% SOC for charge and discharge range and don't want solar to be putting on charge voltage when at 85% as it isn't capable of turning itself off there. I turned in on at about 40-50% SOC on trips this year. We never had to charge off the alternator over a total of about 3.5 weeks over two trips once the solar was on. It is 300 watts so not huge bank. We never really lost SOC on average over the time as we didn't have many days in a row of bad solar. We were not returning on solar on average over about 50ah per day and that covered all our usage so frig use was probably around 30ah per day.

For us 60ah per day would be pretty large amounts over estimating.

We have run our frig on 2 golf cart wet batteries in the past and even with 3 days in a row of bad sun still were OK with no driving for charging.


The OP could be looking at as high as over 90ah per day if the frig listed ran 24/7 cooling and compressor frig would be way less than that.

[The Eyesore]

Thank everyone for chiming in. I think I've changed my mind and decided to go with a compressor fridge and an additional 100Ah LiFePO4 battery to power it.

There's a relatively new brand of cheapo Chinese fridges called Bodegacooler. I'm gonna roll the dice on their new 85L (3 Cu.Ft.) 12VDC RV fridge for $600. This fridge has an app to set/display the temps of freezer and fridge and, I BELIEVE (hard to tell from the lack of availible documentation), it also has a sleep mode which I would certainly use while sleeping to not hear a compressor run. If not, I will just wire in a timer that will allow me to turn off the fridge for 8 hours at the press of a button. Call me a diva, but I love sleeping in silence in my van. I'm totally not okay with the sound of a cycling compressor breaking the spell of silence.

The only thing that worries me is the website of this company is atrocious and the documentation is sparse. It seems that the 85L version of this fridge is brand new to market. I can't seem to find a picture (other than their marketing materials) or review of one, so I'm hoping that they even have them produced and ready to ship.

Wish me luck on this mystery fridge. I'll let you know how it goes after I've tried it out.

[GeorgeRa]

Originally Posted by The Eyesore

Thank everyone for chiming in. I think I've changed my mind and decided to go with a compressor fridge and an additional 100Ah LiFePO4 battery to power it.

There's a relatively new brand of cheapo Chinese fridges called Bodegacooler. I'm gonna roll the dice on their new 85L (3 Cu.Ft.) 12VDC RV fridge for $600. This fridge has an app to set/display the temps of freezer and fridge and, I BELIEVE (hard to tell from the lack of availible documentation), it also has a sleep mode which I would certainly use while sleeping to not hear a compressor run. If not, I will just wire in a timer that will allow me to turn off the fridge for 8 hours at the press of a button. Call me a diva, but I love sleeping in silence in my van. I'm totally not okay with the sound of a cycling compressor breaking the spell of silence.

The only thing that worries me is the website of this company is atrocious and the documentation is sparse. It seems that the 85L version of this fridge is brand new to market. I can't seem to find a picture (other than their marketing materials) or review of one, so I'm hoping that they even have them produced and ready to ship.

Wish me luck on this mystery fridge. I'll let you know how it goes after I've tried it out.

Good luck, RV/Marine compressor refrigerators are very expensive so I am not surprised someone wants a piece of this pie. On one of the pictures the compressor of the smaller Bodegacooler looks like Danfoss with its control panel. The big question for me would be unknown noise and after sale product support.

[jrobe]

Most people choose their RV refrigerator the same way they choose their home refrigerator - the bigger, the better. They want a week's worth of cold drinks and food ready to go just like at home. We have learned to manage perfectly well with a much smaller refrigerator in our RV. We have a 2.7 cu ft compressor refrigerator that hold the equivalent of 2 cases of drinks in food and beverages plus a small freezer. We now only fill it with 1-2 days of pop and beer and then simply restock it every morning. Everything is cold an hour later.

Just learning to use it properly allows us to manage perfectly well with a less expensive refrigerator that takes very little battery power (no where near 60 amp hr per day), that is very quiet (I can't hear it at night and our ceiling fan is much louder), does not require expensive lithium batteries and allowed us to use the extra space for other things in our RV design. I wouldn't overspend on the refrigerator and I wouldn't overthink it.

[booster]

Originally Posted by GeorgeRa

Good luck, RV/Marine compressor refrigerators are very expensive so I am not surprised someone wants a piece of this pie. On one of the pictures the compressor of the smaller Bodegacooler looks like Danfoss with its control panel. The big question for me would be unknown noise and after sale product support.

Not surprising to me that the compressor unit looks like a Danfoss and I would be most of the rest of the unit looks a lot like one of the major players in Rv frigs like Isotherm. The Chinese are kind famous for look alike knock offs the sometimes work OK, but many times are made with much lower quality parts. Just look at all the multimeters that look like Flukes or battery monitors.


I wish him well on this, but my guess is that is 50/50 that it lasts over a year based on what I have seen over time.

[GeorgeRa]

Originally Posted by booster

Not surprising to me that the compressor unit looks like a Danfoss and I would be most of the rest of the unit looks a lot like one of the major players in Rv frigs like Isotherm. The Chinese are kind famous for look alike knock offs the sometimes work OK, but many times are made with much lower quality parts. Just look at all the multimeters that look like Flukes or battery monitors.


I wish him well on this, but my guess is that is 50/50 that it lasts over a year based on what I have seen over time.

I remember the days of “Japanese Junk”, our first Honda Civic CVCC in 1976 was a junk we kept for less than one year, wrenches which bent. Then we had Korean Junk, then we have Chinese junk. There are a few new companies in China capable of making state of the art optics today, successfully competing with Zeiss or Sony. So, let’s hope OP experiment will end with success.

[booster]

Originally Posted by GeorgeRa

I remember the days of “Japanese Junk”, our first Honda Civic CVCC in 1976 was a junk we kept for less than one year, wrenches which bent. Then we had Korean Junk, then we have Chinese junk. There are a few new companies in China capable of making state of the art optics today, successfully competing with Zeiss or Sony. So, let’s hope OP experiment will end with success.

Absolutely, and for a while in the late 1990s it looked like the quality overall in China was on the way to catching up to places like Korea and Taiwan. The place I worked had stuff produced there so was intimately familiar with it all back then. But a bit later cost pressure from other low cost providers put a lot of hurt on China so they had to cut costs and quality tanked on nearly all the mid to low cost items, which was a bit discouraging. I bet there are 10k counterfit Rolexs for every real one now.


The world market is certainly buyer beware.

[The Eyesore]

Update: I just lit the Dometic again and... it's working now! Haha!!

Crisis averted (for now).

Good thing I hadn't ordered the fridge yet! I already ordered the 100Ah battery, but that's okay. Now I'll have a 200Ah system.

[hbn7hj]

Just an FYI

https://youtu.be/CnMRePtHMZY?si=Jngh8YNKl5FXq8HU