"BE" wrote in message

My concern is will this shorten the life of the motor? And, is it ok to
leave the fan on 24/7 for 2, 3, 4, 5 days? My thinking is to leave it on
for whatever the duration of the heatwave. Correct?

Or course it will, the question is how much? Anything mechanical will
eventually wear out. Quality motors with quality bearings can last for many
years. I know of some that have been running 16 to 24 hours a day for well
over 10 years with no problems. I know of some that went to crap in a year.
While you will be using the blower motor more, you already noted the
compressor (the more expensive part) is running less, so why not take
advantage of that?

Keep in mind that starting and stopping also puts a strain on things.
Compressors are often rated with having a maximum of X number of starts per
hour.