Jotul F400 Castine: am I really overfiring it?

[Sparky31]

New stove guy here, running a Jotul F400 Castine.

I followed the manual's diagram and put one of the magnetic thermometers on the right corner, midway from front to rear. Being a data driven kind of guy, though, I'm also checking surface temps with a Fluke 59 Max IR sensor. The break-in is done and we've done about 6 burns since then.

I am confused about the 600 degF temperature limit stated by Jotul. The right corner almost always runs cooler than top dead center. They say to use a thermometer at the corner, but if 600 degF is the limit for that, surely 600 degF is the limit for the other surfaces, right?

Tonight the corner IR temp was 470, but top dead center IR was at 620. The mag mount thermometer is so far off I ignore it now. I immediately cut the air supply and now top dead center is 518 with the right corner at 440. The mag mount says 380.

Is it really OK for the top dead center temp to be over 600 on the F400? Or is 600 a hard and fast limit for any F400 surface?

I want to keep the temps up for best efficiency but I don't want to ruin the stove.

 

[begreen]

Did they change instructions? Our Castine regularly ran at 650F and occasionally spiked at 700F. It's a willing heater. Past Jotul docs simply said 400-650F are optimal stove top temps. 700F tops is a good margin of safety from overfiring.

 

[Sparky31]

My manual says it is version "P04". On page 8 it says the most efficient burn is between 400-600 degF. This is repeated on page 10. However, upon rereading (again!) I don't see a specific maximum temp specified. I may have conflated the language about the break-in with the language on the temperature range.

Page 8 is also where it says to evaluate the temps with a mag mount thermometer placed on either corner of the top plate.

At least it sounds like hitting 620 at top dead center wasn't so bad.

Do you folks agree with using the higher temperature value read, i.e. top dead center?