I noticed in the galley of my new Catalina 375 a hot spot on the counter top below the microwave. I determined right away that the heat was coming from the compressor unit in the front loading fridge below the counter. In the aft cabin I found a vent that supposedly allowed air to cool the fridge compressor.
A simple cheap solution. I purchased a computer 12V (.2 amp) cooling fan and attached it to the vent to suck air out of the fridge compartment. See attached picture. I tied the electrical connection into the engine compartment light for power. The fridge runs much better now and is more efficient. The small fan runs 24/7 unless you turn off the DC master switch to the engine compartment under the Nav station.
I had a similar experience on our C375 #15. The fridge manual indicates there is a fan present in the heat exchanger behind the fridge, in the upper right. I looked through the vent from the aft cabin and noticed that the fan never did come on. This explained why the fridge would compressor would operate for extended periods of time too. I suspected the fan of being defective.
I mentionned this to our local sales rep who found this strange and would have his "refrigeration guy" look at it right away. Right away took a while so I took the fridge out from under the counter. Fairly simple to do, and much easier with a helper. Mounting screws are accessed from the drawer under the fridge. Then just carefully slide out the fridge.
It turns out the fan was not wired right. One of the wires was on the adjacent connector to where it was supposed to be. Just pull connector out and plug back on proper pin. The fan came on right away. The fridge compressor is also running much less.
Note: Isotherm fridge manual is in Catalina 375 Manuals - electrical section (members access only).
Our C320 had a similar issue except the fan was working but there was no outlet vent. That's how I knew there was a fan inside.
Francois Desrochers - C375 Tech Editor
S/V Alizes #15
Lake Ontario
2009 C375