Hitzer 50-93 rear damper door sticking

Hey guys been running a Hitzer 50-93 for about 6-7 seasons now and i still feel like a newbie using the thing.Maybe someone here can help me with a couple dilemmas!
First one is the damper door on the stove keeps getting stuck open after it reaches temp and the stove starts to over burn. Couple times found the side temp at over 600°! Makes me nervous to think it could burn the house down.
The second one is blow back after shaking the stove. I know that it is the residual gases built up from the shake but how do you keep it from making the big poof sound and making my dog run for the hills? Thanks for any help given.

B, are your ash door vents open at all? --try 1/8" if not.

No but i will try that when i shake it next. Thanks

Any positive results yet B??

If the flap is stuck open, first make sure it is not binding and free to move. Next with good light inspect the bi-metal coil for any binding. Work the control back and forth while inspecting.

Normally, after a long burn and ash buildup the flap should be open fairly wide as the stove cools. This provides the extra air to burn gas generated from the fresh coal. If the flap sticks open and the stove is over heating and you manually close the flap before shaking, that can cause the puff back. Find out why the flap is sticking open.

sounds like the bi metallic vent door has a worn spot in it. The pin/that rides in spiral part is worn or spiral plate in there has a flat spot. Take a look up in there from underneath if you can't see, let it burn down coal thats in it, take bi metalic spring bow off back of stove. remove knob and cover and see. Very simple system. Not hard to repair if you understand how it works. Be sure underside fire ash doors gaskets seal tight. door gaskets

You guy's both hit at what i was thinking. Checking the spring and damper door jist good to hear it from others. As for the poofing i tried what another person on here told me to try. Opening the ash pan door slats a little bit for more air flow. Did it tonight and so far no poof but that was only one shake. So we will see. Thanks for the input.

At tending time; If your fire is on the low side, you need to liven it up some before adding coal. You don't want to cover the red hot coals. If you do, chances of a puff back are high. I've had my back flapper door stick open when a puff back. A few things you can do if the fire is low. 1.) Crack ash pan vents open. 2.) Reach under the hopper, and hoe the red hot coals forward just a little. That hole you created will fill with fresh coal dumped in hopper. The red hot coals you hoed forward will ignite the fresh coal. 3.) Without touching the settings, simply turn the fan off. The stove will build heat faster, closing the flapper door.