House was built in 1955. Electric. Does have a hot water heater in the laundry room, but that is in the back of the garage attached to the house, not made noises before, then or since.
No boiler or steam radiators. Heating and ac is all electric. I’m in Phoenix Az.
Sounds like it may have been a case of ‘Sympathetic Resonance’
https://en.wikipedia.org/wiki/Sympathetic_resonance
Something in the refrigerator, possibly the compressor or another part of the system, induced some resonant frequency in another appliance and together they would vibrate in sync until one or the other unit stopped whatever it was doing.
Just a guess..................