Frig tempertures

[DonC]

I've got a Dometic Cr1065 2 way fridge. On hot days 90+ it is difficult to get the fridge temps below the recommend temperature of 40 - I can get to 42-44. I realize that's a 50 degree temp drop and I assume there is a limit to how many degrees of cooling you can get from these fridges. But it does mean that I don't keep certain food in the fridge unless it is 40 or less.

Thoughts? How do you other hot weather campers deal with this?

 

[billharr]

I have the Waeco CR65 I think it is the same fridge. I set the control at "5" and it stays just under 40 and the freezer is frozen ice cream hard. It may run longer on a hot day but the temp stays the same. I did add an extra fan behind the fridge.

 

[DonC]

in my test today I was plugged into shore power at my house and inside camper temperature was 95 degrees - on Thanksgiving Day... my fridge temp low was 42 degrees

 

[billharr]

in my test today I was plugged into shore power at my house and inside camper temperature was 95 degrees - on Thanksgiving Day... my fridge temp low was 42 degrees

What number do you have your dial set at? Does it change if you move the dial?

 

[DonC]

I have it pegged - all the way clockwise
I do get temps in the high 20's and in the 30's on cooler days. But I have difficulty getting to 40 or below, required for food, on really hot days.

 

[Alley-Kat]

How old is the fridge?
You may need a recharge.
Several years ago I had a very small/slow leak, got that fixed along with a recharge and it was working great after that.
Because I live near the ocean, I used a repair guy at a marine supply shop, an RV place should be able to do the recharge and the leak detection.

 

[DonC]

its a Feb 2012 Fleet. They recently had it for a week doing diagnosis. I'll ask about this. thanks

 

[billharr]

I did a Google search and found an interesting thread on a boat forum. OP should read.
Sounds like a low charge or a bad fridge.

 

[DonC]

thanks for the link

 

[RC Pilot Jim]

Bill and Don,
Your frig temperature/solar issue we have been discussing the past week off WTW by email.
The fridge should easily lower the temp inside and hold set temp without running 100% of the time.

I can turn my compressor fridge on in a108 degree day and lower the inside temp from 108* to 39* in 45 minutes running off one battery and hold that temperature for as long as I want with fridge cycling on and off NOT on 100% of the time.

 

[pvstoy]

Bill I read that same link days ago but Don did not mention that his runs all the time. Don does yours run all the time??

 

[DonC]

I wouldn't know if it actually runs all the time without being in the camper all the time. But it is running whenever I'm near or in the camper. I just did a 3 day test and checked voltage at sunrise, 10 am, 2 pm, 4 pm, and 7 pm, and each time I checked it the frig was running.

 

[idahoron]

I put 5-6 bottles of frozen water in each the fridge and freezer to keep the thermal mass as cold as possible after plugging in the night prior. Seems to help.

Sent from my SM-G900P using Wander The West mobile app

I do the same thing. It seems that the fuller the freezer is the better. Frozen water bottles work well.

 

[DrJ]

Bill and Don,
Your frig temperature/solar issue we have been discussing the past week off WTW by email.
The fridge should easily lower the temp inside and hold set temp without running 100% of the time.

I can turn my compressor fridge on in a108 degree day and lower the inside temp from 108* to 39* in 45 minutes running off one battery and hold that temperature for as long as I want with fridge cycling on and off NOT on 100% of the time.

I have the same experience as Jim. The compresser fridge is really amazing and works amazing for me. It also doesn't run all the time even in hot conditions.

 

[billharr]

I wouldn't know if it actually runs all the time without being in the camper all the time. But it is running whenever I'm near or in the camper. I just did a 3 day test and checked voltage at sunrise, 10 am, 2 pm, 4 pm, and 7 pm, and each time I checked it the frig was running.

You should post up your data. I don't think the front door open units were meant to be freezers and might run all the time if below 30 degrees in the fridge area. I would run another test with water in the freezer and water in the fridge. Set the dial at 5 to 6 and see what you get for temps and voltages.

Do you know if your fan on the vent shuts off with the compressor or does it run all the time? My fridge is so quite I have to put my ear near it to know if it is running. I can hear the fan if I am out side by the vent. You can check the vent fan by turning the dial to "0" which will shut off the compressor.

 

[DonC]

Here is an example day from last week. Camper plugged in all night. The next morning unplugged and parked in full sun. 6 sodas in the frig, nothing in the freezer. Frig set to max cooling, frig fan on (the factory fan is either manually turned on or off)

time, voltage, frig/freezer temps


9:30 am, 13.2V, 34/20 (5 minutes after unplugging)
2 pm, 12.6V, 45/20
4 pm, 12.5V, 46/20
7 pm, 12.2V, 40/20

The following day the frig did cool down to the 30's. I have advised FWC that the performance seems very random.

 

[pvstoy]

Refrigators need stuff inside to hold the cold. Stick some frozen stuff in the freezer and more sodas and water jugs in the refg space. Fill it up! Once all this is cold soaked then see if the unit will cycle on and off and maintain a constant temp. You can pre cool the water jugs in your house refg.

Just run the unit with the AC plugged into the camper and give it all the power and amps it needs. Then after a couple of days then see what is going on with the refg. If it runs all the time or will not maintain temp around ~34 degrees then you know you have a problem with the refg and take action to fix or replace.

If the refg is working great and holding temp, and cycling on and off occasionally then park in the sun and unplug the AC current to now trouble shoot the solar system.

Do one known variable at a time that you can isolate.

 

[billharr]

pvstoy that is some good advice. The compressor should be running on 12v all the time. When plugged in it is converting 110v to 12v for the operation. If it runs fine plugged in it will be much easier to find the problem with the 12 v side.

 

[DonC]

Will do. I have had it to FWC once and American RV 3 times for this exact problem. I have asked many times what they did to diagnose the problem - how did they concluded that my frig was ok - and they have never told me what they did.

Given my schedule it will be few weeks before I come back more with this info.

I appreciate all the help here.

 

[RC Pilot Jim]

While we are all digesting the data the following are Don's other numbers for day 2 and 3 of the test:

80 watt panel - Solar only test

time, voltage, inside camper temp, frig/freezer temps


Sat - sunny
6 am, 11.9V, 46, 30/20
8:30 am, 12.4V, 49, 24/20
4:30 pm, 11.8V, 77, 30/20
7 pm, 11.7V, 66, 32/20

Sun - cloudy most of the day
6 am, 11.8V, 52, 26/20
10 am, 11.5V, 72, 26/20
2 pm, 11.5V, 63, 29/20
7 pm, 10.8V, 58, 28/20

Mon - sunny
9 am, 11.1V, 52, 48/48

I thought the controller would shut off to prevent freezing the fridge section even on the max setting?