Got the chimney cleaned results

[ddahlgren]

Last cleaning November 2012 done again today so well over a year. I have kept the temps up using a probe but rarely reach the safe burn zone if at all on a magnetic thermometer. Generally 220 to 240 with the magnetic one but 450 to 550 with the probe . Also burning my fair share of marginal wood along with some bio-bricks. the results are some soot though not enough to fill more than a part of a coffee can and probably closer to a coffee cup. Zero creosote found I stood and watched the entire effort and he ran the brush many times for around 10 minutes. The soot attributed to 14 months of cold starts and lack of creosote the running at 450 or over on the probe for the rest on the time. The message I think is take the magnetic temp reading with a very large grain of salt. Thoughts?

 

[ridensnow23]

The probe will be more accurate because it is actually measuring the temp of the gases. The magnetic is just measuring the temp of the metal. The flue gases can be hotter without the metal reaching the same temp.

For instance, wood gas burns at 1200 degrees in a non cat stove, but the stove itself probably only ever gets up around 500 degrees.

 

[wkpoor]

My thoughts are (without knowing any particulars about your setup)
1: your chimney probably isn't very tall, say 16' or less and your stove pipe is very short
2: if its a steel chimney some or most of last yrs accumulation fell off during the summer.
So your only really seeing approx. 2-21/2 month of accumulation.

 

[ddahlgren]

My thoughts are (without knowing any particulars about your setup)
1: your chimney probably isn't very tall, say 16' or less and your stove pipe is very short
2: if its a steel chimney some or most of last yrs accumulation fell off during the summer.
So your only really seeing approx. 2-21/2 month of accumulation.

1. Yes 5 ft duravent 7ft single wall. so not much.

Big thing for me is over a year little chance of a chimney fire. The value of a probe is another point to be made in my mind as well.

 

[bholler]

yes a probe is much more accurate but a surface thermometer will still give you a good reference. the main thing is that a probe will respond much quicker and it will always read higher than the surface as long as the probe is the right length. it should be either 1/3 or 2/3 the diameter of the pipe to be in the hottest area of the pipe. the center and the outer edges are a little cooler. but really we don't need to be that particular we mainly need a general and consistent reading of the flue temps. and wow that is a short stack do you have issues with inconsistent draft?

 

[ddahlgren]

yes a probe is much more accurate but a surface thermometer will still give you a good reference. the main thing is that a probe will respond much quicker and it will always read higher than the surface as long as the probe is the right length. it should be either 1/3 or 2/3 the diameter of the pipe to be in the hottest area of the pipe. the center and the outer edges are a little cooler. but really we don't need to be that particular we mainly need a general and consistent reading of the flue temps. and wow that is a short stack do you have issues with inconsistent draft?

The point I am trying to make with the probe is I have spent over a year below the 'burn zone' about 70% of the time yet had just a little soot after almost 14 months.

Draft can be an issue on windy days or if there is any sort of inversion going on. It sure does heat up quick though. I suspect the lack of creosote is because the gases do not have enough time to cool down.