AB Compressor Cycles Too Often

[Richard Kollmann, Kollmann Marine Inc.]

RE: Compressor Cycling Too Often

The problem you describe could be caused by a fault sensed by the electronic module but it is more likely the thermostat control. The efficiency of the Adler Barbour and similar units depends on the correct installation of the thermostat. The thermostat control must be located far enough away from the evaporator so that the condensation that collects on it will not freeze and prevent the switch from operating. Repeated cycling of the thermostat can normally be traced to its temperature sense capillary tube touching the evaporator and sending a false signal. The capillary tube is to be kept away from the refrigerant tubing and evaporator except for the area where it is clamped to the evaporator.

 

[Rick D]

A dockmate’s A/B compressor and fan will kick on and run normally for approximately 30 to 45 seconds and shut off. If he leaves it turned on the interval gets shorter. The power and charge seem OK. Any suggestions?

 

[Patrick]

Does the unit keep cool?

I have personally seen several 5-6 compressor units which do this. Three have been on my own boat. I have read about this same problem on the web. It is apparently a very common problem. The compressor will run normally for a few minutes or even hours and cool the fridge ok but then start to cycle on and off endlessly. Once the cycling starts, it stops cooling. After a few hours off, they do the same thing again. The guys in Florida tell me that it is a common problem, that it is the controller, and that it is a $100 repair. No other help from them.The bottom line for me is that it is likely a simple electronic fix but no one will provide the schematic for the controller or tell me what is the likely failure. Typical service marketing / planned obsolesence for some "marine" and many computer products. Looking at the controller tells me that there is no part on it that costs much more than $.50 at Radio Shack. I am not willing to periodically pay $100 for a repair which I can do myself for $.50. Richard, do you have any ideas, suggestions, or perhaps a schematic?