Harman TL 300 questuion

I don't know how the blower would effect the temp that it registers.
But, you shouldn't turn on the blower until it gets up to the proper temp.
Starting your blower to soon will cool off the stove.
If you notice that it drastically effects the reading you may want to try placing it in the upper right hand corner just above the door.

Another option is to contact, James04 he also has the TL-300 and he uses a flue thermometer.

I also have a TL 300. I plcae my thermometer right on top, right above the fire. This gives me the reading for the hottest point on the stove. It is an interesting question about how the blower would come into play. I will have to check that out this season.