Let's say I have our (Norcold) fridge temperature set on level 5 and the temperature is holding steady. But if the outside temperature goes up or down the fridge temperature does too. If it goes up, I have to change the level to 6 or 7 to keep the fridge temperature from getting too high. If the outside temperature goes down, I have to lower the setting to 4 or 5.How does one deal with this situation without constantly playing with the level setting?

It is possible to get a replacement sensor that has a "dial" on it. I have not tried this--but apparently they give better results that the eyebrow buttons.I have a twelve volt fan that helps circulate the air which helps.In summer time it is important to use the drain tube in a manner that creates a "trap". That prevents warm outside air from comming up the drain tube.

This does not make sense, for a correctly operating refer. You set at 5 and lets say that gives you a temp of 38 degrees. REGARDLESS of the outside temp, the refer WILL RUN to keep that temp of 38 degrees. Setting it to a lower (8) will NOT make the refer maintain the 38 degrees faster. Unless you are opening and closing the refer too much, but even so, the temp set of 5 will still maintain 38 degrees. ALL the temp setting does is run the refer until the set temp is reached. I hope you are not like my wife and think that when it is 80 degrees in our house, setting the AC at 65 will cool the house down quicker than setting at 70 degrees:B Changing the set temp on an RV refer will not decrease the time it takes to reach set temp. I will bet you have some sort of digital temp sensor readout? Now, I would replace the Temp Thermister. Cheap to do and a BAD Thermister will still OHM out and test good. Doug

Some (all?) Norcolds have a diagnostic thing you can do as explained in their manuals. You can check for a thermistor fault etc.

Hi dougrainer,If I understand you correctly, #5 setting is (for example) 40 f. So the fridge will be in cooling mode until the fins are 40 f? Then it cycles " off".But the sensor clips onto the cooling fins. They cool the fridge by convection of the air inside the cavity. So adding a fan may help to even out the temperature in the fridge?I'm always grateful for your insights into these items. I do know that the Norcold from my 1987 RV appeared to work better than the Dometic in my 2005 RV.

Our Norcold which is usually set at 6 will vary between about 33 and 38 with no correlation to outside temp. (No way to explain it as due to outside temp variations.) I replaced the thermistor, but that had no effect. A couple of years ago, it was getting up into the low 40's so I called a mobile tech. He installed baffles in the rear of the fridge which should have been done when I bought the new trailer and the dealer swapped out the residential for the Norcold. That improved the performance during hot weather and kept it below 40. Since then, have learned to live with the inside temp variations.

Fridge temperature depends on ambient | Good Sam Community

MEXICOWANDERER
Explorer
Jun 21, 2020
I cut my teeth on lithium bromide liquid absorption chillers. The units are 25' in length, weigh 9 tons, and require a boiler and cooling tower. There wasn't one on the face of the earth that was automated. Even though these systems utilize cooling towers and fans a more change in wind direction required manual adjustments. Note the plural, adjustments...

You do not want to know what happens if the lithium compound overheats.

Now mix in complexity with lowball construction cost versus longevity. Be thankful if your absorption unit performs to your expectations of performance and longevity
Edd505
Explorer
Jun 21, 2020
What model? There is an issue with the 4 door models.
red31
Explorer
Jun 21, 2020
As a manual reader I've seen this in both norcold compact and dometic

Maybe the OP could share what fridge is in his truck camper?
dougrainer
Nomad
Jun 20, 2020
red31 wrote:
some of those small fridges sans freezer DO NOT HAVE A TEMP CONTROL (thermostat), you are the thermostat, the propane flame is adjustable from small to smaller.

The have a temp control. It is called a BYPASS TSTAT on the LP side. I have never seen a small RV LP/120 refer NOT have a tstat. The tstat control is usually on the OUTSIDE back of the refer. You have to open the outside access door to get to it. The BYPASS tstat works like this--- You light the LP burner and IF the refer needs to cool, the flame is normal flame. When the refer inside temp is reached, the BYPASS Tstat lowers the LP flame to a pilot level and stays lit, but not enough BTU's to operate the cooling unit. When the refer needs to cool, the Bypass tstat raises the flame to normal level to cool. Doug
red31
Explorer
Jun 20, 2020
some of those small fridges sans freezer DO NOT HAVE A TEMP CONTROL (thermostat), you are the thermostat, the propane flame is adjustable from small to smaller.
pianotuna
Nomad III
Jun 20, 2020
Just to elaborate on dougrainger power comment

Power varies by the square of the voltage.

120 x 120 = 14,400

115 x 114 = 13,225

That represents a power drop of over 8%

If the wattage on the fridge is 325, at 115 the power is reduced by over 25 watts.

Just another reason I love my autoformer--even in winter.
MEXICOWANDERER
Explorer
Jun 20, 2020
Food safety
Freezing hazard

Were my primary commandments.
opnspaces
Navigator II
Jun 20, 2020
hedgehopper wrote:

How does one deal with this situation without constantly playing with the level setting?

My solution is I just don't worry about it.
dougrainer
Nomad
Jun 20, 2020
pianotuna wrote:
Hi dougrainer,

If I understand you correctly, #5 setting is (for example) 40 f. So the fridge will be in cooling mode until the fins are 40 f? Then it cycles " off".

But the sensor clips onto the cooling fins. They cool the fridge by convection of the air inside the cavity. So adding a fan may help to even out the temperature in the fridge?

I'm always grateful for your insights into these items. I do know that the Norcold from my 1987 RV appeared to work better than the Dometic in my 2005 RV.

Fin temp is 10 degrees COLDER than the temp in the refer. The Thermister senses the FIN metal temp. Now, HOW you pack the refer makes a BIG difference in how well it cools. You need at least 1 inch space on the back wall for convection air to flow UP that back wall and THRU the fins to remove the heat. Plastic ziplock bags and such inhibit this air flow if pushed against the back wall. I think you mentioned the Drain tube for the evap drain pan. Norcolds have a Check Valve installed in the end of that tube that stops outside hot air migration to the inside. Dometic's need that "P" trap loop to prevent that air migration, but I would bet 99 99/100 of Dometic installs do not have that P trap made. Yes, the small battery operated fan inside the refer blowing air up thru the fins will help a lot. Lots of variables on temp hold. How long you open the door. How OFTEN you open the door. Putting warm/hot items in the refer. WHAT your CG 120 line voltage is. WHY? Because most use the Auto function which will operate on 120 if 120 is connected. The Line Voltage can drop dramatically if you have lots of RV'ers and they have their Roof AC's on. The 120 element will NOT put out the required heat to cool the refer better/faster if the line voltage is below 115 volts. When your line voltage is low, run on LP until the line voltage increases. There are lots of variables that HOME appliances do not have to put up with, but RV appliances do. Having a DIGITAL 120 volt wall plug readout is a must for any RV'er. The plug in NEEDLE type voltage readouts are useless. They have too great an error range for accuracy. Doug
CarnationSailor
Nomad
Jun 20, 2020
Our Norcold which is usually set at 6 will vary between about 33 and 38 with no correlation to outside temp. (No way to explain it as due to outside temp variations.) I replaced the thermistor, but that had no effect. A couple of years ago, it was getting up into the low 40's so I called a mobile tech. He installed baffles in the rear of the fridge which should have been done when I bought the new trailer and the dealer swapped out the residential for the Norcold. That improved the performance during hot weather and kept it below 40. Since then, have learned to live with the inside temp variations.