Have a Carrier Gas Furnace Model #58MSA. Has stopped working and code #23 comes up, which the owners manual states have service call. Live in area where service calls are hard to come by and am also a DIY type of person. Any suggestions. Thanks Steve

Look on the back side of the blower access door for a legend as to what exactly the code 23 means.

I am guessing pressure switch stuck closed but that is just a guess.

If code 21


21 GAS HEATING LOCKOUT - Control will NOT auto reset.
Check for: - Mis-wired gas valve -Defective control (valve relay) (circuit board)

Just waiting to see what code 23 means. Then I will try to help. Make sure you are reading the blinking lights correctly.