Dometic Side x Side Reefer not cooling

[possum]

I have a Dometic Mod. No. RM1350SLMX refrigerator (4door) and am again having trouble keeping my food cold during the summer months. The food compartment is running at 47-52 deg. and frzr is 17-19 deg. Dometics operating specifications for the food compartment is 38-43 degs. and 0-12 degs. for the freezer. Food and Drug Administration says refrigerated food is to be kept at 40 degrees or below. Dometic has replaced the Cooling Unit, the fans, and the two heating elements (for electric operation of the cooling system) which failed. They have installed baffles in the outside exhaust grill opening (upper grill). The door seals are good. It works great during the spring and early summer season but now is again having trouble cooling during the peak summer months July , August, September. The unit is 18 months old and each year during the summer season it fails us. It's still under warranty and I will be taking it back in to get it fixed. It's in a 2019 Reflection 303RLS fifth wheel. Any one else experiencing this problem with their Dometic reefer??

[TheLexx]

I have a Dometic Mod. No. RM1350SLMX refrigerator (4door) and am again having trouble keeping my food cold during the summer months. The food compartment is running at 47-52 deg. and frzr is 17-19 deg. Dometics operating specifications for the food compartment is 38-43 degs. and 0-12 degs. for the freezer. Food and Drug Administration says refrigerated food is to be kept at 40 degrees or below. Dometic has replaced the Cooling Unit, the fans, and the two heating elements (for electric operation of the cooling system) which failed. They have installed baffles in the outside exhaust grill opening (upper grill). The door seals are good. It works great during the spring and early summer season but now is again having trouble cooling during the peak summer months July , August, September. The unit is 18 months old and each year during the summer season it fails us. It's still under warranty and I will be taking it back in to get it fixed. It's in a 2019 Reflection 303RLS fifth wheel. Any one else experiencing this problem with their Dometic reefer??

Unless there's something seriously wrong with your fridge, Dometic will likely just pooh pooh the matter. The problems with the 4 door Dometic are well documented here on this forum and other places. There are two issues. It's cooling effect is only by diffusion. There are no fans internally. Diffusion is a poor way to cool things down. You can add some fans on the cooling fins like these:



More than likely that still won't be enough. The biggest problem is for many folks, the fridge is in the slide, and when the slide is out, the sun is beating down almost directly on to the fridge. You have lower and upper vents (the ones with the blackish removable covers behind the fridge). Cool air is supposed to enter the lower vent and escape out the upper vent. The problem is this really doesn't happen. So folks have added intake fans on the lower vent and exhaust fans on the upper vent. I just finished adding the interior fans on the fins, and radial fans on the lower vent. It seems to help, as I had the slide out and was able to keep the fridge below 39° on a day where temps go to 99°. I plan on adding big 140 mm computer fans to the upper vent to draw out the hot air.

Check out my thread on the subject. There are other threads here if you do a search: https://www.mygrandrv.com/forum/show...907#post299907

[nwminnesota]

I have a cheap battery powered fan that I leave on the top shelf of the fridge pointed at the cooling fins.
It works pretty good.

I had one time where I couldn't control temp. What I found was the door didn't close all the way. I was surprised by it because it barley hit the object inside.
Also to note that the hottest weather I have camped in was about 95 degrees.

[TheLexx]

Today it's 99° outside again. And with my slide out and the hot sun bearing down on the slide and thus the fridge, my half-full fridge reads 33°. But no one has been in and out of it except for once this morning. Nevertheless, it is indeed performing much better than it had been previously when it couldn't hold below 45° on a day like this.

[zenasboy]

Today it's 99° outside again. And with my slide out and the hot sun bearing down on the slide and thus the fridge, my half-full fridge reads 33°. But no one has been in and out of it except for once this morning. Nevertheless, it is indeed performing much better than it had been previously when it couldn't hold below 45° on a day like this.

I've found the temp display on the outside of the fridge is not to accurate and typically reads 3-7 degrees lower than actual temp. I have the same fans as you do and have the same temp of 33 now showing on the display, but separate thermometer inside shows different. I will say, that I also added a 120mm fan on in lower outside access panel that run continuously pushing air up and I added some metallic tape and flashing in the top access panel to help funnel air out and I do get readings on my thermometer placed in the fridge around 35 degrees. Even last month in Badlands National Park when it was 103 degrees out. I notice the biggest difference between fridge thermometer and separate thermometer to be when it goes into defrost. Fridge will show 35-36 but thermometer will read 40-42.

[TheLexx]

I've found the temp display on the outside of the fridge is not to accurate and typically reads 3-7 degrees lower than actual temp. I have the same fans as you do and have the same temp of 33 now showing on the display, but separate thermometer inside shows different. I will say, that I also added a 120mm fan on in lower outside access panel that run continuously pushing air up and I added some metallic tape and flashing in the top access panel to help funnel air out and I do get readings on my thermometer placed in the fridge around 35 degrees. Even last month in Badlands National Park when it was 103 degrees out. I notice the biggest difference between fridge thermometer and separate thermometer to be when it goes into defrost. Fridge will show 35-36 but thermometer will read 40-42.

If it's an actual 40-42, that's already a massive improvement. Previously we could not hold below 50°. I thought the fridge was broken, but then as soon as we got into cooler weather it got back to safe temps again.

[TheLexx]

Ok update. Today we drove 3.5 hrs from our 99 degree area to the coast where it’s 66. By the time we got there the fridge read 44 degrees. That’s a terrible outcome.

[RoJoSo]

I have a Dometic Mod. No. RM1350SLMX refrigerator (4door) and am again having trouble keeping my food cold during the summer months. The food compartment is running at 47-52 deg. and frzr is 17-19 deg. Dometics operating specifications for the food compartment is 38-43 degs. and 0-12 degs. for the freezer. Food and Drug Administration says refrigerated food is to be kept at 40 degrees or below. Dometic has replaced the Cooling Unit, the fans, and the two heating elements (for electric operation of the cooling system) which failed. They have installed baffles in the outside exhaust grill opening (upper grill). The door seals are good. It works great during the spring and early summer season but now is again having trouble cooling during the peak summer months July , August, September. The unit is 18 months old and each year during the summer season it fails us. It's still under warranty and I will be taking it back in to get it fixed. It's in a 2019 Reflection 303RLS fifth wheel. Any one else experiencing this problem with their Dometic reefer??

We have a 2020 303RLS 5th Wheel.
I'm having the same exact issue and nearly the same exact temps as you. The dealer and GD have told me that it is in operating specs. I was also told the the unit reaches the 48 to 52 degree mark because it automatically defrosts. They recommended that I turn the unit off and on at 2/3pm in the afternoon to set the recycle of the defrost so that I will defrost at night (2/3am). I find this to be totally unacceptable. When I mentioned to them the FDA specs, (after I googled FDA temps) they referred me right back to the units operating specs. How can this be safe? Is Dometic liable if one gets food poisoning? AUGH!

I should have the unit back in about a week from having additional warranty work being done. I will test the fridge on my own and see what happens (documenting everything). If the unit fails I will be contacting GD/dealer again and go from there, I have read on other posts that contacting Dometic is no help with this issue. I will be making a call to them as well, even though I have no faith in them helping me out in any way.