ERPARKER, TBL01, and BUDMAN - thanks for the replies.
Initially, my wood may have been a little damp from recent rains, but it is seasoned, and I have since moved a small amount into my garage to dry off before I burn it. But it sounds like I am still in that beginner phase. To me it seems pretty random when the blower kicks in but usually 30 to 90 minutes. And I have been closing the by-pass soon as the fire was strong enough to keep going on its own (with the damper wide opened). And I have been cracking the doors to get the fire roaring - but it sounds like my big crime is closing off the bypass too soon - and possibly not waiting for the fire to get hot enough (in regards to the damper).
As far as the thermometer and temperatures go - I am in the blind without even having one. I will get a magnetic one and position it as you two have - so at least I can compare numbers. Is there a free standing thermometer that could be set behind the faceplate and there peered at thru the vent holes using a flashlight (similar as to what TBL01 mentioned)?
Also, during one recent fire the secondary combustion tubes started glowing! I take it this is too hot? It was not intentional - the damper was closed all the way!
As far as heating goes. I have a single story rambler 1400 sq ft built in '66 with an exterior fireplace. Over the past weekend the temps dropped just below freezing to 28 F. The fireplace end of the house was 74 F and the bedroom end was 66 F (There is a vaulted ceiling that separates the 2 sides of the house.) I am very happy with the insert - as last year there was a 8 day power outage and after throwing log after log into the opened fireplace we could only get 55 F in the one room - the rest of the house was 40 F.