I have a Philco No-Frost side-by-side refrigerator/freezer bought in 1970.
The freezer does not stay cold enough. I am using a freezer alarm that goes off when the temperature gets above 15 deg F:
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can't get the freezer to stay below 15 degrees for more than a few hours. I wrapped the alarm sensor in foam and put it at the bottom of the freezer, consistent with the instructions.With the freezer door open, sometimes I notice a boiling or sizzling sound just like the sound of water dripping into a hot skillet or onto a hot stove. Is it supposed to make that noise?