Compressor refrigerator

[Keith]

2010 Northstar 850sc bought in 2016. Fridge failed to light 2017. Replaced at cost of $1800.00, used 1 week in 2018. Went to sierras this August, freezer cold lower box 70 deg. Just got back from rev shop, cooling coils have blockage, out of warranty. Disgusted with Dometic absorption fridge considering compressor unit. Who makes the most reliable one and what do I need to keep it running (batteries solar power etc)?

[ardvark]

Keith, if you still have the fridge, before you drop the coin for a compressor model, did you try “burping” the one you have (i.e. disconnect and stand it on its head for 24 hours provided the top compartment continues to cool down)?

Steve

Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SC

[Keith]

Thanks for the reply. I pulled it out yesterday because I figure it’s going to have to come out one way or another anyway. I did flip it over and back upright four times. I did hear the liquid trickling down through the tubes each time. I did not let it sit for 24 hours. Also I saw a YouTube video where a fellow said that method does not work because crystals form in the tubes and block it up. The RV shop I went to said that is true that they can get blocked up by crystals and that the upside down cure may work for six months but it is not a permanent fix. It has been running on my patio since yesterday afternoon and the freezer is 6° the bottom 40° as of 8 o’clock this morning. Well go out and check it now that the day is hotter and see what’s happening.

[ardvark]

Keith,

#1. Your refrigerator is working, the coil is not blocked. A blockage can recur, but it also may be good for the next ten year, speaking as a Dometic factory trained Master Certified RV tech. That statement is based on my real world experience running my own repair center for 30 years.

#2 To test a fridge for function, take a half gallon of water in a container and put it in the fridge with the door closed for 24 hours, then measure the temperature of the water. If it is 43 degrees or less, you are at factory spec. There is nothing the matter with your fridge.

#3 I don’t understand why your first fridge was replaced simply because it did not ignite. That is a simple repair and sometimes doesn’t even require parts.

#4 If you are going to trash a good fridge and are anywhere near Tennessee, can I have it? 🙂

Steve

Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SC

[Keith]

left all the temp readings with the RV shop so he can speak with Dometic this morning. But freezer was getting to 6deg and box 20-70deg as the day heated up. In my experience the tube closest to the heater would be too hot to touch for any length of time. this unit i can grab the tube and hold on to it no problem. The 110volt unit is very hot, not running on gas as it is on my patio now. Replaced the old unit because when i went on the internet to try and get information on the problem i read that it would be the regulator and or circuit board. Both parts were in excess of $300.00 so i figured that the unit being 7 years old i did not want to put that money in it and have the cooling unit start leaking ammonia in another year. Will try your suggestion of the 1/2 gallon of water but do not have much hope that it will show the unit is not broken as when on last vacation i essentially did that text with 3 1/2 gallons of milk and other food items and the fridge did not get below 50deg during the day that was in the low 70’s

[ardvark]

Hi Keith,

I am glad you are taking another look, even if it turns out I am wrong. In the olden day to rule out cooling coil versus controls, we used to do what was callled “hot sticking” which mean we simply wired the electric element directly which takes all the controls out of the circuit. If the box then cooled it was a control issue as you were operating the cooling coil constantly. If it still didn’t work, you needed a coil. Your shop should know how to do this.

Usually when the burner tube gets so hot it will burn the skin off your hand, the coil is blocked, but they all get hot when working.

I am anal retentive when it comes to diagnosis as the simplest thing to do and the thing that makes the shop the most money was to simply sell a new fridge. 🙁

Steve

Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SC

[Anonymous]

Keith, I’m only going to address the compressor refrigerator part of your question. In 2013 I replace my 3-way unit after one failure after another, on and on. For my 2002 Lance 815 after a lot of research the Dometic CR1110 was the best fit for my rig. I haven’t had one regret for making the change. There are several makers of RV/ Marine compressor refrigerator and most of them use the same Danfross compressor, there are thing you’ll have to consider if you make the change to a compressor refrigerator and that has to do with supplying electrical power to the unit. My solution for that was going to a second much larger battery (interstate 4D) tied in with my truck electrical system. This has work well since 2013 for me but the 4D battery does weight a 100 lbs. With Li batteries coming to play a bigger part in the TC area I myself will be converting to the those Li battery.

Just a note that there are a lot of YouTube on this subject and as well article(s) in this website. If you decide to convert to a compressor refrig. post your project it will help others who are considering the same thing.

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