Air conditioning does “run” like a runner runs, but a joke is:
 
Q: Why did the AC compressor sweat?
A: Because it had to run all day.
 
The joke was posted on Twitter by HVACEDONLINE on May 28, 2011.
 
       
Twitter
HVACEDONLINE
@HVACEDONLINE
Why did the AC compressor sweat?
Because it had to run all day.
9:15 AM - 28 May 2011
   
Twitter
Harding Heating&Air
@HardingHVAC
Why did the AC compressor sweat?
Because it had to run all day.
12:30 PM - 12 Apr 2012
   
Twitter
CARE Heating Cooling
@CARE_Heating
Why did the AC compressor sweat?  Because it had to run all day.  #hvachumor
10:25 AM - 21 Apr 2012
   
Twitter
Mid-State HVAC
@Midstatehvac
How about a laugh to break up your day.  Why did the AC compressor sweat? Because it had to run all day!
1:01 PM - 2 Jun 2012
 
Twitter
Comfort Htg & AC LLC
@ComfortHtg
Q; Why did the AC compressor sweat? A: Because it had to run all day.
3:57 PM - 6 Jun 2018
 
Facebook
A & G Air Conditioning Services
July 2, 2018 at 10:02 AM ·
Why did the AC compressor sweat?
Because it had to run all day.