Does a 2-way refrigerator do a good job of staying cold in high ambient/outside temperatures?

Bayliss

For those who have a 2-way refrigerator in your T@B, particularly those who have replaced their original 3-way model, what has been your experience as far as the refrigerator staying cold when the ambient/outside temperature is in the 90's, or low 100's?

Denny16

Our Norcold 2-way keeps food cold, even with temps in the high 80s outside, not tested with higher temps, but the inside of trailer did,get in the low 90s and the fridge was at 42-44F.  The new Isotherm Elegance 65 is netter yet, featuring Danfoss compressor, which is more efficient and uses less power in the process. 

Cheers 

manyman297

We have the Isotherm mentioned above in our 2021 400 BD. It’s great at temps below the 90s. Really struggled in the upper 90+ temps. But this was on a trip where our generator didn’t work and were stuck using the vent fan to cool the interior.

What really makes a difference is the interior temps. If you can get the interior cool using the AC then the fridge works great. I’ve seen some people add additional fans behind the fridge to help move the hot air out from behind it. But if the interior of the camper is hot then it doesn’t do much good. 

Tabnero

I have been in very hot conditions and the Iso therm did a supper job. I have wireless thermometer and and at 103 out side I think we got up to 42 inside but not for long. frozen food area was fine. it was set at 4.5

Mickerly

I have a 2018 320 CS. The Norcold has an older Danfoss compressor. It keeps my food in the upper 30's low 40's in west Texas where is stays 100 day and night when set on 3. The Isotherm is about 8 years newer design, it may work better, but the Norcold 751 works fine.

Denny16

Thanks @Mickerly that is the same fridge in our 2018 TaB400, didn’t realize it was a Danfoss compressor also.  It does a good job for us in the 80s and lower 90s.  The only failures on this fridge I am aware of, have been the thermostat or thermostat board, which is an easy fix.
 Cheers 

Bayliss

Thank you to those who have responded thus far.  The information is very helpful.  If anyone else has additional input, I'm all ears!

johnfconway

Still waiting to get under bed storage emptied. Once that happens, will do the final experiment. Combine mid-90s ambient temperatures, trailer in shade, portable solar panels in sun and new 2-way refrigerator hopefully staying below the 41 degree threshold.

Here is link to earlier experiment -- testing the new 2-way refrigerator in "warm enough" conditions. https://tab-rv.vanillacommunity.com/discussion/13775/norcold-n3104-replaced-with-isotherm-freeline-115-in-t-b-400#latest

Denny16

John, you are using a larger Isotherm 115, that is a 12/24VDC Marine type fridge, and I have a feeling it would work better on 24VDC, and is struggling at higher temps when running on 12VDC.  The larger compressor in this fridge running on 12VDC is less efficient than if it was running on 24 VDC, and a Q12VDC takes more amps, than it would at 24VDC.

The nüCamp provided smaller 2-way fridges in this discussion are 12VDC only units, with a smaller compressor, that is more efficient than your larger unit whilst running on 12VDC.

An interesting experiment would be to see if you can set the fridge to 24VDC and power it with two 12 volt batteries to see if it works better?

Cheers 

johnfconway

@Denny16, we are very happy with performance of Isotherm 115 fridge. We do not expect it, or any other refrigerator to perform well when cabin temperatures exceed 100 degrees (as they do when ambient is in 90s and trailer in full sun).

First experiment was a huge plus for the new 2-way. Next experiment should demonstrate shade on trailer while still charging from portable panels allows 2-way refrigerator to keep food safe in the hottest of temperatures (at least in high desert southwest).

Denny16

Grand John, good luck with your experiments.  I thought testing it on 24 VDC vs 12VDC would be an interesting experiment to see if the voltage makes any difference?

cheers

Bayliss

Thanks for the info and link, @johnfconway.

AZGal

I have had major problems with my 2021 T@B 400 Boondock Solo with 2 Way fridge! I boondock lots. If I camp in sun so that solar panel charges battery (in 70s-80s), then the camper at rear gets real hot and so does the fridge!  I've tried fans inside but since the camper is hot it doesn't help much. This because the fridge is vented in and out inside the rear of camper. Why not OUTSIDE venting?!! My model has large fridge on kitchen side. 

Thinking to buy a portable 12V fridge to carry in 4Runner which I have put Solar panels on top to charge a Kodiak solar generator I carry there. Any suggestions?

bergger

We have the 3-way fridge in our 400 and use it primarily for food, with a few drinks stored in the door.  On our long trips, anything longer that a weekend, we use a portable 12v compressor fridge that is kept in the backseat of our truck, powered by our Jackery 1000.  We use that to cool most of our drinks and any food items that won't fit in the trailer fridge.  We have an IceCo VL45 and love it.  I've had engle compressor fridges and also dometic compressor fridges in the past.  The IceCo has the same compressor as the more expensive ones and is way cheaper.  We've been using it for a couple of years with no issues.  I highly recommend them. 

https://icecofreezer.com/products/iceco-vl45-portable-refrigerator-freezer

grassgd

AZGal said:

I have had major problems with my 2021 T@B 400 Boondock Solo with 2 Way fridge! I boondock lots. If I camp in sun so that solar panel charges battery (in 70s-80s), then the camper at rear gets real hot and so does the fridge!  I've tried fans inside but since the camper is hot it doesn't help much. This because the fridge is vented in and out inside the rear of camper. Why not OUTSIDE venting?!! My model has large fridge on kitchen side. 

Thinking to buy a portable 12V fridge to carry in 4Runner which I have put Solar panels on top to charge a Kodiak solar generator I carry there. Any suggestions?

I'm in the process of replacing my Norcold N180.3 with a 2 way unit in my T@b 320 and concerned about venting the unit to the inside of the trailer to avoid poor performance in hot weather like you reported. 

Most replacements on the T@b302's utilize the extra space when switching to a 2 way refrigerator for additional storage, but I am looking at using it to duct outside air in an out through the original side vents in hot weather and then being able to easily switch it to venting inside in cold weather to capture the heat inside.

Just in the "design" phase but looks very doable. 

Bayliss

@grassgd, I will be interested in what you come up with.

As you have probably already seen from reviewing posts regarding installing the Isotherm Cruise 65 Elegance two-way, I chose it to replace my Isotherm.  So far, it has worked great.  Much better than the Norcold N180.3 and it is really nice to have the freezer compartment.

Initially, I left the side vents open to get plenty of fresh air to the refrigerator.  However, I have since blocked off those vents, because too much cold air was entering the trailer cabin.  We took a three-month trip last fall (approx. 20,000 miles), before I closed off the vents, and we had a lot of cold air entering the trailer cabin via those vents.  Air primarily flowed in and under the refrigerator, which is raised about an inch above the cabinet base as required for proper operation.

I suppose that installing some sort of ducting to the side vent(s) might be configured, but it will likely be difficult.  There will not be much space to run ducting, because the refrigerator body is a perfect fit and the compressor/fan are located at the top rear of the refrigerator.  There is space on the side of the refrigerator that is adjacent to the external vents of the trailer, but how to direct air (fresh or exhaust) from/to those vent(s) may be challenging.

This past March, after closing off the vents, we took a 4,000 mile trip between Arizona and Ohio (nuCamp) and had no issues.  The weather was primarily cold, but we didn't have cold air blowing in through the outside vents.  I did also modify my installation of the refrigerator to allow the refrigerator compartment to have better air circulation (by adding a few round exhaust vents above the refrigerator), but it is the same as you and @AZGal have described (i.e., the refrigerator both brings in fresh air and vents hotter exhaust air from inside the trailer cabin - - no external venting.)  I do keep the roof vent open partially, or fully, plus I at least crack open one or two windows to promote better air circulation within the trailer interior.

We will be taking another three month trip later this summer and will be in both hot and cool/cold regions of the U.S./Canada, so that should be a good test of how I currently have everything configured.

Mickerly

Camping in the sun is a problem for everyone. These trailers have an Aluminum heat sink for a ceiling. If you have a newer trailer with a glued on solar panel, you have an additional heat source. Shade is the key to success with an aluminum topped trailer in the summer.

By the way, this is also the source of cold in the winter causing our condensation problems.

gulfarea

@Mickerly You are so correct about the roof being a heat sink! On my 320 for solar I went with the Light leaf solar because it leaves about 2 inches of air under the panel for cooling. It is also removable to put in the sun if you are in the shade. No I am not affiliated with them at all! Art

grassgd

Bayliss said:

@grassgd, I will be interested in what you come up with.

As you have probably already seen from reviewing posts regarding installing the Isotherm Cruise 65 Elegance two-way, I chose it to replace my Isotherm.  So far, it has worked great.  Much better than the Norcold N180.3 and it is really nice to have the freezer compartment.

Initially, I left the side vents open to get plenty of fresh air to the refrigerator.  However, I have since blocked off those vents, because too much cold air was entering the trailer cabin.  We took a three-month trip last fall (approx. 20,000 miles), before I closed off the vents, and we had a lot of cold air entering the trailer cabin via those vents.  Air primarily flowed in and under the refrigerator, which is raised about an inch above the cabinet base as required for proper operation.

I suppose that installing some sort of ducting to the side vent(s) might be configured, but it will likely be difficult.  There will not be much space to run ducting, because the refrigerator body is a perfect fit and the compressor/fan are located at the top rear of the refrigerator.  There is space on the side of the refrigerator that is adjacent to the external vents of the trailer, but how to direct air (fresh or exhaust) from/to those vent(s) may be challenging.

This past March, after closing off the vents, we took a 4,000 mile trip between Arizona and Ohio (nuCamp) and had no issues.  The weather was primarily cold, but we didn't have cold air blowing in through the outside vents.  I did also modify my installation of the refrigerator to allow the refrigerator compartment to have better air circulation (by adding a few round exhaust vents above the refrigerator), but it is the same as you and @AZGal have described (i.e., the refrigerator both brings in fresh air and vents hotter exhaust air from inside the trailer cabin - - no external venting.)  I do keep the roof vent open partially, or fully, plus I at least crack open one or two windows to promote better air circulation within the trailer interior.

We will be taking another three month trip later this summer and will be in both hot and cool/cold regions of the U.S./Canada, so that should be a good test of how I currently have everything configured.

Still working out the details.  I am trying to use a Vitrifrigo C62iXD4-F (2.2 cu ft) instead of the Isotherm Cruise 65 like most people use.  Waiting for Vitrifrigo to provide some details on the dimensions missing from what's online. The Vitrifrigo is made in Italy instead of China is the reason for choosing it in my case.

Here are a couple sketches showing the concept:


Above shows upper and lower existing vents with existing vertical board which I will leave in with a hole cut in the lower portion as shown below.



Above sketch shows new plywood (in blue) to isolate upper and lower hot and cold air with a new small storage area in between. In the above sketch you can envision venting the refrigerator from the interior of the trailer or from outside. The yellow is the existing framing of the front counter.  This would allow conservation of heat in cold weather to heat the interior and in cold weather not to heat the trailer interior with simple blocking the vents inside the trailer above and below the storage area and installing removable vent covers on the existing vents in the trailer wall (hope this makes sense).

What's not shown is the baffling to isolate the cold air across the top of the refrigerator and compressor and hot air after the condenser fan to force the hot air down between the outer front shell of the rv and the back of the refrigerator to the hole cut in the bottom of the existing insulated board left in from the old refrigerator that most people remove.  By pulling cold are in the upper vent also reduces the dust pulled into the trailer when on dirt roads, hopefully anyway.

The baffling is difficult to describe and likely to be worked out during installation.  I have in my mind some details but need to work on it more.

Bayliss

Thanks for the drawings, @grassgd.  I do have a pretty good idea of your approach to the venting.  The design of the Vitrifrigo appears to be very similar to the Isotherm.  I see a couple potential issues, but a lot depends on the manufacturer's installation specifications.  For the Isotherm, there has to be space for air to flow in below the refrigerator, up the left side (when looking toward the door), and then out to the right side (with assistance from the fan that blows the air in the direction of the trailer's side vents.) 

As you are likely already aware, my Isotherm (and the nuCamp installations, I believe) has the refrigerator propped up on a couple risers/runners below the feet on each side so fresh air can enter below the lower front of the refrigerator.

(1)  Should your air flow be reversed, with cool air entering from the bottom and hot air venting out the top?  Hot air rises, so that seems necessary.

(2)  IF you do have to raise the refrigerator in a similar manner, the right side runner (closest to the side vents) will likely block most of the air flow under the refrigerator.  (You might be able to install the runners in a side-to-side orientation, rather than front-to-back, but it might make installation of the refrigerator a bit more difficult, but not necessarily impossible.)

Here's a photo of the runners I am referring to.  Hopefully, what I have described makes some sense.  Also, just for your info, the top of the Isotherm just barely slides under the stove's propane regulator depicted in the photo, so be sure to factor that into your planning.

It looks like you are on the right track.  I am looking forward to seeing how it all turns out.

 

grassgd

Thanks for the comments Bayliss.  The Vitrifrigo installation instructions actually don't show units with the compressor/condenser mounted on top but with it mounted on the bottom, but I assume the requirements would be the same - no requirement for venting under or around the sides at all, hence no runners required.  Simply an opening requirement on the inlet and outlet sides.

I realize I am trying to force hot air to go down to exit. I could reverse it but if I can, I would like to pull air in the upper vent to reduce dust pulled in when on unimproved roads.  If needed I could add an additional fan in the cut opening in the existing support to the countertop.  I'm counting on the fan or fans (if additional fan is needed) to force the air down.  But even after installation, I could reverse the air flow.

Since I don't have to raise the unit up on runners, it will clear the stove regulator since it's no taller than the Isotherm unit so I should have about 1" clearance.

The dimensions I'm waiting for are the compressor/condenser overhang on the back side and details on the triangular bottom corner of the box to verify clearance with the trailer front wall.

The unanswered question is the effective openings to ensure sufficient airflow since it's not simply an outlet to a vent on each side of the unit. I need to get my mind around that issue, but worst case that can be solved with and additional fan to aid the one on the condenser.

Bayliss

It sounds like you are doing a good job of thinking it all through, @grassgd, so it should all work out.  Keeping the dust out will definitely be an issue to deal with, but it is hard to get around that.  The real test for the Isotherm I installed will be later this summer when I will be travelling through areas with higher temperatures at times.

grassgd

Bayliss,  I look forward to hearing how you make out with higher temps.  

I ordered the Vitrifrigo.  Although the web site said they had 5 in stock, they didn't and shipment isn't expected until end of this coming week. 

I'm confident I can arrange the cooling air and hot air exhaust from either the interior of the trailer in cold weather to help heat the interior or from the outside via the existing side vents when desired or needed.  Will update once I get to work with the unit after receiving it.

BrianR

I installed a Dometic CRX50 this spring. We haven't been in any hot weather yet but last weekend I left it on 4 after initial cool down and it froze the milk. 

Mickerly

Compressor refrigerators work much better if you are interested in keeping food cold. The propane refrigerator works when electricity is limited.

johnfconway

This post/discussion was 3-way Norcold (a dangerous disaster in hot weather) replaced with a quality 2-way Isotherm. https://tab-rv.vanillacommunity.com/discussion/13775/norcold-n3104-replaced-with-isotherm-freeline-115-in-t-b-400#latest

Trailer temperatures were about +8 degrees F over outdoor. I think above 92 degrees outdoors (and 100 in trailer cabin), you will cross the 41 degree food safety max for awhile. If you can stay out of the frig, it will drop below 41 degrees reasonably quickly as cabin temperatures retreat.

Bluetooth thermometer in refrigerator a wise investment. It's amazing how quickly a relatively tiny refrigerator jumps in temperature when door is opened and 100 degree cabin air rushes in!

This prompted suitcase solar panels in hot weather so (if possible) trailer can be parked in at least partial shade and avoid 100+ degree cabin temperatures.

Marceline

johnfconway said:

This post/discussion was 3-way Norcold (a dangerous disaster in hot weather) replaced with a quality 2-way Isotherm. https://tab-rv.vanillacommunity.com/discussion/13775/norcold-n3104-replaced-with-isotherm-freeline-115-in-t-b-400#latest

Trailer temperatures were about +8 degrees F over outdoor. I think above 92 degrees outdoors (and 100 in trailer cabin), you will cross the 41 degree food safety max for awhile. If you can stay out of the frig, it will drop below 41 degrees reasonably quickly as cabin temperatures retreat.

Bluetooth thermometer in refrigerator a wise investment. It's amazing how quickly a relatively tiny refrigerator jumps in temperature when door is opened and 100 degree cabin air rushes in!

This prompted suitcase solar panels in hot weather so (if possible) trailer can be parked in at least partial shade and avoid 100+ degree cabin temperatures.

People might also want to be aware that the Norcold manual says that the Norcold 740 automatically shuts down when the ambient temperature reaches 100F to protect the compressor. I don't know about the other models. Last year I was camping in very hot weather (100F+) and I couldn't understand why the fridge stopped running. It doesn't start up again until it cools to 80F.

grassgd

Received the Vitrifrigo C62iXD4-F (2.2 cu ft) today and started installation to enable venting to be switched from inside the trailer during cold weather to conserve heat and outside through the existing side vents in hot weather.  Actually, could pull air from inside the trailer and exhaust to outside if needed in extreme hot weather when on shore power and AC running. Will post some pictures of the install once it's finished.

grassgd

Bayliss said:

It sounds like you are doing a good job of thinking it all through, @grassgd, so it should all work out.  Keeping the dust out will definitely be an issue to deal with, but it is hard to get around that.  The real test for the Isotherm I installed will be later this summer when I will be travelling through areas with higher temperatures at times.

Basically finished the installation.  See some details in post titled "

Norcold 180.3 Out and Vitrifrigo C62IXD4-F In"

Dragonfly4100

I bought my T@B 320 CS about two months ago and even though I haven't run the fridge in 90+ temps yet, I have been taking steps to help out with the efficiency of the unit and since the fridge is in a very enclosed space in the clamshell model, I figure that anything I can do will help. Step 1 was to remove the fridge and insulate the sidewall with 2.5 inches of styrofoam insulation. Step 2 was to wrap the sides, top and rear of the fridge box with that reflectix (silver bubble wrap) insulation sold at Home Depot/Lowes and tape the corners with aluminum duct tape. Step 3 was to drill a 3" diameter hole through the sidewall and install a clamshell vent (see "A" in picture). Step 4 will be to drill a 4" diameter hole with a curved clamshell vent through the hatch above where the fridge is (see "B"), I haven't committed to this one yet.......almost afraid of going through this hatch so I just have the vent taped there to see if I like it. Should I install "B" ?????
 The idea with the vents is to create a convective flow of air, which should help at least a little. 

Marceline

Dragonfly4100 said:

I bought my T@B 320 CS about two months ago and even though I haven't run the fridge in 90+ temps yet, I have been taking steps to help out with the efficiency of the unit and since the fridge is in a very enclosed space in the clamshell model, I figure that anything I can do will help. Step 1 was to remove the fridge and insulate the sidewall with 2.5 inches of styrofoam insulation. Step 2 was to wrap the sides, top and rear of the fridge box with that reflectix (silver bubble wrap) insulation sold at Home Depot/Lowes and tape the corners with aluminum duct tape. Step 3 was to drill a 3" diameter hole through the sidewall and install a clamshell vent (see "A" in picture). Step 4 will be to drill a 4" diameter hole with a curved clamshell vent through the hatch above where the fridge is (see "B"), I haven't committed to this one yet.......almost afraid of going through this hatch so I just have the vent taped there to see if I like it. Should I install "B" ?????
 The idea with the vents is to create a convective flow of air, which should help at least a little. 

I've wanted to do the hole in the sidewall but have lacked the courage. I've thought about one on each side for cross-ventilation. My concern about the vent is possible water ingress if driving in the rain. Maybe a marine-style vent with a screw-in deckplate? My concern about your plan for "B" would be what happens when you have the clamshell open and it's raining? 

I've been looking at some solar powered car and chicken coop ventilation fans as a way of getting the air moving around in there when the T@B is parked and hatch shut during the day with the fridge run (gone for a hike or whatever). I'd run the wire through the hatch and stick the solar panel to the roof with a suction cup or something.