I agree with “party lines”.
I would add:
_black and white TV.
_floor furnaces.
We had central heat as most people did. However our house was extremely drafty. And my father kept the thermostat at 60. No wonder we all dreaded taking a bath all winter.
And my cousins’ family farm house had central heat on the main floor, but only an opening in the main floor ceiling with a grate on the floor above. The heat was supposed to eek its way through to the bedrooms above. I recall staying over several times when there was frost on the inside of the windows. They eventually got electric blankets for everyone to make it bearable.
This was in rural Iowa in the 60s