Reznor F50 fan cycling (limit switch)?

[sprchrgd1]

My garage furnace fan cycles on and off quite frequently until the exchanger warms up completely. I really don't want it 65 to 70 degrees in the garage while I am in there just to keep the fan from cycling. Anyone have any tips as far as limit switch settings where I could keep the furnace set at say 50 degrees and not have the furnace fan kicking on and off?

 

[bookman51]

Might be a bad fan delay switch. I had that on one of my Farenhart electric heaters.