Q: At a mechanical system, a level working space of at least _____ inches by ____ inches (deep and wide) should be provided in front (or at the control side) of the appliance for service and maintenance and inspection.
A: Answer is here
According to which code, Ben? IRC Mechanical Code requires 3 inches and 12 inches (IRCM 306.1.1), respectively. Then, it allows exceptions for installations into existing spaces that conform with the manufacturer’s instructions.
Did you ever think of making reference to your sources for answers, since there is no single answer to the majority of these questions throughout the USA?
I was going with 36x30, but I got my winter weight on
30x30
with 24 walk way no more than 20 ft long
Now…we also have some NEC clearances to the electrical portions as well we would like …care to guess what they are?
Without using a measuring tape, I like to have an arm’s length of open workspace in front of the electrical panel (and both arms width wide in front of the panel too).
Hey Ben, FedEx me one of your arms. 
Speaking of arms, my brother Nick has an arm span that is longer than his height. Very unusual for human beings.
My arm span is probably longer than Nick’s height, so???
By two feet?!
WOW :shock:
That is an amazing differnence.
Just like a gorilla…sorry Nick, Ben left you open on that one.
Does he drag his knuckles?