On my 10th season with my Kuuma Vapor Fire 100.....

[brenndatomu]

Rough rule of thumb is that external mag thermometer reads about half of what a probe type will...

 

[brenndatomu]

I have a thermocouple mounted in the stovepipe right outside the VF, it very rarely goes over 400*F...if it does that usually means that either the HX needs cleaned, or computer is turned up, not on low anymore.
280-350 is a pretty normal operating for me, on low, which is where it stays 95-98% of the time for us...might move it up to medium for a "polar vortex" in January occasionally.

 

[R Henderson]

I have to concur with this I stuck one of those magnet gauges on just for fun a few days and I stayed mostly 175 to 205. So likely internal temp would be over the 250 threshold. However I have found that it burns so clean the temperature swings doesn't really hurt it none. These are very easy furnaces to run by far the safest imo. I have a very similar setup 2 45s about a 20" section of single wall, somewhat shorter 18' chimney 6" insulated stainless inside large brick through middle of house. Baro been on 4 the whole time and flaps fairly regularly.

 

[Jwilly]

Thanks for all the responses everyone. Sounds like my magnetic thermometer is right on track then. My only concern now is the ice build up on my famco wind cap. My chimney is a 25' tall cinderblock chimney on the exterior of the house, and i have a 6" liner running down it. I wonder if i should have insulated it... hmmmm

 

[brenndatomu]

I wonder if i should have insulated it... hmmmm

Yup!