Whitfield Quest WP4 Questions (New to pellet heat)

I just moved into a new house over the summer and it had a pellet stove insert (begin my obsession with pellet heating!). As far as I can tell its a Whitfield Quest WP4. The number under the pellet door is wh-q 28975. The previous owner said it is a 1999 but I think it might even be older.

At first it would shut off after 10 minutes of running so some helpful searching on the forum caused me to replace the low limit switch. Now electrically it works perfectly.

Couple things I have noticed. The damper even at the very lowest setting seems to bring a ton of air into the burn pot. I usually have to run it on the lowest damper setting even with the highest feed rate. Turning it any higher shoots half burned pellets into the side ash trays. Is that normal?

Also I seem to get a "dead" area in my burn pot towards the front of the ultra grate after running for more than 8 hours. I scrape it and it just reforms in another 8 hours. I am using maine woods pellets. I am not giving it enough air to the burn pot?

One last thing. I have a 1600 sqft cape from 1950 that is far from tight. When its over 35 the stove can crank the whole house. Below freezing it can't keep up at all. Does anyone know if this is too small of a stove for this house? I love love love the manual aspect of tuning the Whitfield and am wondering if I should consider looking for a bigger Whitfield insert on CL.

Any help would be appreciated for a pellet newb

It has a knob based damper adjustment that is connected to a cable. I traced it to the back of the stove. I can't find anywhere to adjust it.

Thanks for all the replies!

I confirmed the cable is connected to the swing arm and it does move with the damper adjustment knob. It seems like a small movement of the damper control moves the swing arm quite a bit! With the last bit of turning it left moving it a seemingly HUGE amount. It seems fairly fluid but without seeing inside its hard to know if it goes all the way closed or not.

I think you are right and I have way too much air getting to the pot.

To access the damper do you suggest pulling the whole insert out and working from the back or can I slide it out a bit (without disconnecting the exhaust) and get at it from the top?