"Jim Sherman" wrote in message
news
I'm a snowbird and worry about a furnace failure while I'm away. I've
heard that there is a temperature sensing switch that will turn on a lamp
if the house gets too cold. I'd like to set a lamp in the front window so
my neighbor can check the place as he drives by without coming inside.
Does such a switch exist? Who sells it? Thanks in advance.

How far away does the neighbor live? You could just get one of those remote
thermometers and put the sensor that you would normally put outside in your
living room and give the neighbor the inside unit. He could then check the
actual temp regularly.