Fridge - works on AC but is 'weak'

chilly81 wrote:

-Or could the AC element just be degraded - not working as well as it once did, and would be worth replacing that element?

Most likely this, but not as in being defective.

The problem is more than likely due to low voltage, as mentioned above which is a very common problem in campgrounds, esp. in the summertime with a lot of folks running AC units. The Norcold electric heating element is rated 300 watts at 120 volts. 120 volts is the standard nominal voltage of electric appliances and devices in NA (with a few exceptions) and is the voltage listed by Norcold.

The output of any electric heater with a resistive element in it varies as the square of the voltage. At 108 volts, the output of the heater would be (108/120) x (108/120) x 300 = 243 watts (down by 19%). If the voltage got down to 105 volts (not unusual), the heater output would be (105/120) x (105/120) x 300 = 230 watts (down by 23%).

When the CG voltage gets really low (around 105), you can see it will take quite a bit of capacity away from the heating element and thus cooling capacity when the outdoor temps are getting high. Unless you invest in an autoformer, running on propane is the solution. It would help to have a power line voltage monitor plugged into a receptacle inside so you can always see what is going on.

As an aside, when voltage gets down below 105 volts, it leads to damaging AC units. An EMS unit like a Progressive Industries (highly recommended) or a Surge Guard will automatically shut your incoming power supply off and protect AC units and anything else that can be damaged by low volts. If you encounter low voltage frequently, getting an EMS is very cheap insurance.

Low voltage is an RV-ers nemesis. We're at a CG in Wa. that has been as low as 105 volts and I get lukewarm coffee out of our coffee maker. Pffft...