The fan blower for a coleman mobile home furnace stays on and begins to blow cold air before shutting off, how do I know if the fan/lower limit switches are the right ones? Model # 7680C856 80,000 BTU.

Go to this site

mobilehomerepair.com :: Index (http://www.mobilehomerepair.com/phpbb/index.php)

It is dedicated to mobile home owners. Has much information to offer. They specialize in HVAC also. BTW They have a part number model cross reference.