I've noticed many people report that their typical startup procedure with a cold stove is to wait until the stove top temperature reaches 500ºF before beginning to turn down the air. That might work for a small, thin shelled steel stove that reacts quickly to temperature change. but it can be much too late for a stove with a lot of mass to heat up. In today's modern stoves the firebox is often insulated to help the fire get up to temperature as quickly as possible so that secondary combustion and clean burning commence. If the wood is dry the fire can have robust secondary combustion long before the stove top reaches 500º. It's better to use your eyes or a flue thermometer to determine when to start closing down the air, than relying on stove top temp. Turning down the air earlier reduces stress on the stove and on the flue system and it can extend burn time.
Flue temperatures are read with a surface thermometer on single-wall stove pipe or a probe thermometer on double-wall stove pipe. A good point to start turning down the air is about 300º on a surface thermometer and 500º on a probe thermometer. A probe will be a bit more accurate as the probe is directly in the hot flue gas stream. You will need your eyes to determine how quickly to turn down the air and how much. This will depend on several factors like how dry the wood is, the thickness of the splits, the species of wood and the strength of the draft. A good starting point is a 50% reduction with the air control half closed. If the fire gets lazy at this point, then wait a few minutes to let it regain strength. If the fire is still burning very strongly, reduce the air another 50% down to 25% (1/4) open. If the fire is very weak or smoldering then open up the air control until the fire regains strength, then try closing down the air again in 5-10 min..
Examples:
As noted, the setting for the air control will vary, but with dry wood and large splits on a cold start I would typically be starting to turn down the air on the Jotul Castine (F400) with a probe flue temp of 500º even though the stove top temperature was only 350º. From that point the air was turned down incrementally over the next 10-15 minutes. After about 40 minutes the stove top would finally be at 500º.
This morning I reloaded the Alderlea T6 on some hot coals. The is a heavy stove with a lot of mass. The stove top temp was 225º. The doug fir pieces I loaded were on the small side and ignited quickly. I returned to Hearth.com, typing up this posting and went a few minutes past when the timer went off. When I got to the stove there was a big ball of flames inside. The flue temp was at 1000º! and I could smell the paint baking. I turned down the air all the way and the fire settled down quickly. At this point, the stove top temp was only 285º. Had I waited until the stove top reached 500º I would have definitely overfired the stove and seriously stressed the flue system, not to mention wasting a lot of fuel. The stove top did reach 500º about 20 minutes later.
As one can see, with a secondary combustion stove, flue temperatures are more helpful than stove top temperatures. I mostly go by flue temperatures alone for guidance and by the look of the fire. For us, the stove top temperature is only relevant for avoid overfiring and if we are going to be cooking on the stove top. This guidance is for non-cat stoves. For a catalytic stove follow the manufacturer's guidance. A catalytic thermometer is a good guide for when to close the bypass and regulate the air.
Flue temperatures are read with a surface thermometer on single-wall stove pipe or a probe thermometer on double-wall stove pipe. A good point to start turning down the air is about 300º on a surface thermometer and 500º on a probe thermometer. A probe will be a bit more accurate as the probe is directly in the hot flue gas stream. You will need your eyes to determine how quickly to turn down the air and how much. This will depend on several factors like how dry the wood is, the thickness of the splits, the species of wood and the strength of the draft. A good starting point is a 50% reduction with the air control half closed. If the fire gets lazy at this point, then wait a few minutes to let it regain strength. If the fire is still burning very strongly, reduce the air another 50% down to 25% (1/4) open. If the fire is very weak or smoldering then open up the air control until the fire regains strength, then try closing down the air again in 5-10 min..
Examples:
As noted, the setting for the air control will vary, but with dry wood and large splits on a cold start I would typically be starting to turn down the air on the Jotul Castine (F400) with a probe flue temp of 500º even though the stove top temperature was only 350º. From that point the air was turned down incrementally over the next 10-15 minutes. After about 40 minutes the stove top would finally be at 500º.
This morning I reloaded the Alderlea T6 on some hot coals. The is a heavy stove with a lot of mass. The stove top temp was 225º. The doug fir pieces I loaded were on the small side and ignited quickly. I returned to Hearth.com, typing up this posting and went a few minutes past when the timer went off. When I got to the stove there was a big ball of flames inside. The flue temp was at 1000º! and I could smell the paint baking. I turned down the air all the way and the fire settled down quickly. At this point, the stove top temp was only 285º. Had I waited until the stove top reached 500º I would have definitely overfired the stove and seriously stressed the flue system, not to mention wasting a lot of fuel. The stove top did reach 500º about 20 minutes later.
As one can see, with a secondary combustion stove, flue temperatures are more helpful than stove top temperatures. I mostly go by flue temperatures alone for guidance and by the look of the fire. For us, the stove top temperature is only relevant for avoid overfiring and if we are going to be cooking on the stove top. This guidance is for non-cat stoves. For a catalytic stove follow the manufacturer's guidance. A catalytic thermometer is a good guide for when to close the bypass and regulate the air.
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your tee, pipe or liner. Not that I have ever done that. 
Agreed also that the operator must stay on top of what is happening when ramping up a load; Temps soar in a hurry if you have a good bit of air feeding a load that quickly takes off. Use your phone timer to keep from getting distracted. I'm not a fan of running the air wide open for very long when ramping up, although that will vary depending on draft and what stove you run. I have 16' of stack and I am running at around 50% air in less than 10 minutes. I never want to see a "ball of flames" for the reasons you mention..localized stress to stove and chimney parts.
