[Bubbles17]

Why dose my furnace blower alway blow in High speed? I oly runs for so long then quits & starts right afert that. I will show a code of 33 during the cycle & then it will show a code of 13 after it shuts down. What can I do to fix these problems?

 

[NiNe O]

What do the codes mean? Should say on the door somewhere

 

[Bubbles17]

13 means Limit switch lock out. & 33 Limit or flame roll out switch is open

 

[NiNe O]

Roll out switches are the switches around the burner box, they must be manually reset by pushing the button on them. Limit switch has auto reset . Try resetting roll outs and cycle heat

 

[NiNe O]

How's your filter?