IF you turn them ON then they will only actually run when the fridge is above the temperature setting. If it's below that it will simply sit there in stand by mode until it needs cooling inside the fridge. Pretty much the SAME thing happens in summer time as if the fridge ran all the time it was "turned on" it would freeze everything in the fridge. There are no gradiations of "on" with an RV fridge (or any other type), they simply run a higher percentage of the time when they need more cooling.
2011 F-150 HD Ecoboost 3.5 V6. 2550 payload, 17,100 GCVWR -
2004 F-150 HD (Traded after 80,000 towing miles)
2007 Rockwood 8314SS 34' travel trailer
US Govt survey shows three out of four people make up 75% of the total population