ARB Fridge doesn't seem to be staying cold for as long as it used to

[dfinn]

I've got an ARB Classic 50qt, maybe 5 years old and I've got the insulation wrapper on it.

Lately it seems like it's running very frequently and just doesn't stay cold for as long as it used to. Today, it's an overcast rainy day in Oregon and it's maybe 70 degrees. I've got the back hatch open to give the fridge plenty of airflow. The fridge kicked on and got down to 36 degrees about 2 hours ago and it's back up to 43 now. The fridge is full but not stuffed, there's a mix of "normal" stuff in there (beer, soda, meats, veggies, dairy). I don't have any data to go on but it seems like it used to stay colder for longer. Anyone else have much to compare that to?

I probably wouldn't even notice it but I'm struggling with an undersized house battery and no sun for solar today so I've been keeping tabs on it. On warmer days it seems like it runs almost non stop.

 

[NatersXJ6]

Do you have an actual thermometer in it, or are you just going off the display temp?

A good first step would be knowing if the display is accurate.

 

[Herbie]

Also, your battery problem might be your fridge problem.

The efficiency of the compressor motor changes with the input voltage. If the battery is headed south, the compressor won't be as efficient, which further stresses the battery in a feedback loop

 

[john61ct]

Yes a fresher battery putting out higher voltage, less sag when the fridge cycles

can make a big difference.

But also seals stiffen, insulation breaks down, refrigerants leak. . .

 

[dfinn]

I’m dealing with the battery situation shortly but what I’m observing with the fridge is how quickly the temp (yes, I’m using the built in gauge) rises in between the compressor cycling.

I feel like in the past it would have stayed colder for much longer in between cycles

 

[NatersXJ6]

You can change the thermistors in them. I’ve never done it, but it sounds pretty easy.

I would verify it against a second thermometer first.

Not that this will change cycle times, but I would also make sure the coils and compressor compartment are completely clean.

 

[john61ct]

Yes any change blocking airflow over the hot bits can have a big impact.

But if the temp sensor is right that seems more like insulation failure or leaking seal on the hatch?

 

[dfinn]

I regularly blow out the fan and coil area with compressed air and I do usually notice a slight improvement in how it operates when it’s nice and clean. But I’m more focused on what is happening when it’s not running.

I’ll get a dedicated thermometer when I get home and compare it to the LED screen.