insert-- stretching out burn time

[mainstation]

Hello I have recently installed, professionally, a Regency I2400. The exterior chimney is fieldstone, approx 30' high facing Northwest. The installers told me they had to use 5" SS flex instead of 6". The chimney is straight up. I have been burning this unit for about a month and have noticed it burns well but overnight burns are non existent---maybe 4-5 hours max. It draws really well even with the insert draft closed, the door seal is new. The wood is well seasoned hardwood, hard maple/ash. I was wondering if there is anything I can do to improve burn times, or is the height and diameter of SS flex drafting the fire? Any help/opinions are welcome thanks.....

 

[stejus]

How big is the box? Is it under 2 cu/ft? I have an HI300 which is a Regancy masked with a Cast Surround and I can get 8 to 10 hour burns.

 

[BrotherBart]

What are you calling an overnight burn? At the end of the 5-6 hour burn is there a bed of coals in the firebox?

 

[mainstation]

What are you calling an overnight burn? At the end of the 5-6 hour burn is there a bed of coals in the firebox?

Well, I would like to see 6 hours for an overnight burn. I am waking up to small glowing coals, fine ash in the morning. I can usually resurrect the fire with a bit of split cedar kindlin and some Ash splits. I have this theory in my head that the 5" is acting like a big straw and burning the wood not neccessarily too hot, just too quick and I was wondering if anyone had any similiar problems with tall chimneys and smaller SS flex. Any remedies or advice? The stove is approx 15 years old, R14 Regency, with a cast plate on the plenum , instead of the firebrick shelf I had on my I1100.