Gas and Oil Home Heating Furnaces - furnace cuts off

Bare with me please, this is my first time trying this on the internet. I have a coleman gas furnace. The problem is that the automatic reset limit switch keeps cutting the furnace off. It appears as if everything is working as advertised. The unit is only 9 mo. old and has only been used for the last 4/5 mo. I have a seperate A/C unit outside that worked fine throughout the summer. I'm curious if it could be the blower speed set too low for heating mode? Any help would be greatly appriciated.

Thanks!

Rich

you are referring to the high limit, you may need more airflow due to undersized return, or very possibly dirty indoor coil from the a/c. at this age it is fully under warranty. get a tech out there.

Have you been doing the preventive maintenance on it (at least new filters and belt if it has one)? If the air filter is dirty, this is exactly what should happen!:(

Being an authorized Coleman repair service in Arizona for residential and manufactured home units, I agree with HVAC4U's advice. There are several probable causes for high limit switches tripping off ranging from lack of airflow to ignition/fan board problems and should only be repaired by an authorized repair service, otherwise, your warranty could become void. If your unit was installed by a state licensed contractor then you need to call the installing company first as they are the one responsible for warranty work on the furnace. If you cannot contact the installer, consult the warranty paperwork that came with the furnace for instructions on who to contact or you can call Norris Air in Tempe/Phoenix for assistance.