Holding plate bulge

 I just got back to Sweet Dreams after being away for seven weeks and found that my Grurnert holding plate had bulged about 2 in and now leaks. The pressure was strong enough to break a metal shelf bracket and bend a 1/4 inch plastic shelve almost in half.  The refrigeration was off while I was gone and all three doors to the freezer and refrigerator were propped open. Does anyone know why this happens.

My boat is hull #63 from 1975 with the original Refrigeration which has worked flawlessly for the last 19 years I have owned her.
Thanks,
Dennis Pelletier
Sweet Dreams, Hull #63

Sounds like corrosion inside the plate.

We try to keep ours running even if away to keep the presures down in the summer heat.
Have you tried pumping down your system into the resevoir before shutting down for extended periods? The old original manual explains the process. This prevents presure buld up in the system as temp and pres go hand in hand. Sorry to hear, we are hull #71 and our old Grunert is still making ice cubes..............for now.