Another Refrigerator Runs Continuously Problem

[JESSEDIVER49]

I have a 30 year old Grand Banks with a single engine room-located refrigeration system for my separate freezer and refrigerator boxes. Each box has its own EV and temperature control. It's a Grunert holding plate system with fan-air cooled condenser. System still cools freezer to 30 degF but control system does not work properly and compressor runs 24/7. Old control system has a box with 2 magnetic relays to turn 110v motor on/off from temperature controls. Questions - should I just replace entire system with something modern? if so, like what, Sea Frost, or ? is there a new "control system" I can buy? I've already asked Grunert and still waiting for response but it appears response will be an entirely new Grunert system.

 

[Giggitoni]

Our GB is 29 years old and has three boxes attached to the original compressor. About two years ago, maybe three, I noticed that it was remaining on for longer periods of time. I had a marine service tech come out to check things out. He had to add coolant to the system and checked for leaks (there were not any).

It's been running strong ever since. Our system runs for about 20 minutes then shuts down for an hour or more depending on the ambient temperature.

The tech showed me a little window on the compressor. It's a window to see the coolant circulate around the system. It's a good thing to not see bubbles rushing by the window. If there are bubbles present, then the system may need additional coolant.

Something to check out. BTW, I leave the system on 24/7, even when I'm gone.