Stack Pipe Temps

Don't know if this data will help or not since mine is not a boiler and is much smaller btu-wise than yours, but on the 90k mag stoker after running full out it will get to about 280* on a 2" probe temp gauge inserted into the 6" flue pipe about 15" up from the exhaust. The stove temp will be about 600* on the upper sides which is the hottest part, read with an IR temp gun. Interestingly the IR will read about the same as the probe gauge on the flue pipe.

That is interesting that the IR reads the same on the exterior of the smoke pipe as the 2" probe. I'm thinking of investing in a IR temp reader. What make and model do you have and are your pleased with it?

This is the one I have, it wasn't very expensive and I found it on amazon if I remember correctly. I only use it for the stove or to drive the cats nuts so my use is limited but it works fine for me.
I will post a pic of the IR and probe gauge at some point when the stove has been firing for a while to show the temps each is displaying. It is idling a lot this morning since it is not very cold here.

Found a previously posted pic at idle for comparison of IR versus probe gauge reading:
with a better angle of the probe gauge face:

AA130, w/ it's 5" breech, goes from standby, then w/ a heat call, then back to standby, internal stack temp at 20" does max out very near 300F

Now understand that this temp is after 2 passes, back and forth the length of the boiler in different layers of water jacket.

The fire/flame/heat is entering the water jacket by a large fan into the jacket at around 1000F in a rapid cyclonic vortex motion for the 2 passes.
When the CO gases light off at the top of the fire pot, there is a muffled roar as if a oil gun was ignited. inside there. Haven't measured this temp..but it's near 300F out at the stack as mentioned.

I know all about that roar!! When I open the fire pot plate at full run it is pretty incredible to see, hear and feel that heat.

Picture is worth a thousand words:

Well, I picked up a IR temp gauge at HF today. Seems to work fine. Things are addictive!

Here are some temp readings. The first shows the temp of the side of the boiler. The second is the reading on the outside of smoke pipe adjacent to the internal gauge. (Note difference). Third is the reading on the fire port opening plate. (Hot!!!)

Can anyone tell me how to convert a movie taken on my iphone (.MOV) to one that I can upload to the site (WMV, etc.)???

Townsend wrote:Can anyone tell me how to convert a movie taken on my iphone (.MOV) to one that I can upload to the site (WMV, etc.)???

Email it to your computer, use windows movie maker to save it as a wmv file.

Townsend wrote:Here are some temp readings. The first shows the temp of the side of the boiler. The second is the reading on the outside of smoke pipe adjacent to the internal gauge. (Note difference). Third is the reading on the fire port opening plate. (Hot!!!)

Your IR gun measures much more area than the laser spot. In the comparison of smoke pipe and internal temp. The gun is also measuring the probe dial and probably the control near it. I would expect a 100 degree difference.

Franco, the directions with the IR gun explained the measuring cone. I took multiple readings on the pipe from different distances including the back area from where the internal gauge is. I used the previous pic because it showed both readings. All measurements were consistent with approx. 225F.

Hi Townsend. I see your boiler is uninsulated. You should definitely insulate your boiler. It will cut down on fuel consumption, and lead to an increase in steam generation. The increase in efficiency is worth it. There are some folks that will tell you to not insulate it, but it is illogical, as the purpose of the boiler is not to heat the surrounding space, but to generate steam or hot water to send to the radiators, and / or generate hot water with the coil. Keeping the boiler uninsulated, heats the surrounding space at a far greater expense than adding a radiator above the water level that drains into the return, or to add a hot water zone, or add a steam coil to an indirect blower to supplement the direct steam radiation.

The best way to insulate the boiler would be fiber-blanket (ceramic, or the soluble one) covered with fiberglass lagging cloth, and cover that with lagging paste (bridging encapsulant). Once dried, you can put a nice coat of paint on it.

For applying the fiber blanket, you can either tack weld the little clip rod to the boiler, or just slide some steel or copper wire through the fiberblanket and twist it tight with pliers. They actually make fancy lagging wire pliers. Running the wire on the outside will leave a little indent, which you could always use the fiberglass tape to cover the indent.

You will also want to insulate your steam distribution piping from the boiler on. This will all help increase efficiency, save fuel and get steam to the radiators faster.

All the best to you. Glad to see you back.