jrsdws said:According to the manual: "The #2 heat level light is flashing- The stove’s vacuum switch tripped."
Just verifying then try this on for a moment when you increase the combustion air by opening the damper the flame becomes a lot hotter, that is why the color changed, the now hotter exhaust gases try to get out the exhaust but there is a downslope (looks like that from where I sit based upon the pictures) this down slope actually retards the flow of the gases allowing the temperature to build around the combustion blower, one the temperature there reaches the thermal protection limit the blower shuts down, this causes the controller to toss the #2 vacuum error.
This can also happen if there is enough back pressure in the exhaust to cause the pressure to drop below what the switch requires to stay closed causing the controller to toss the #2 vacuum error.