snap disk to cut off fan ?

[lotawood]

Apologies to the OP for the hijack.

TC, I had looked at a ceramic sheath to lengthen the life of the thermocouple. Maybe I need to find the bargain kind. The prices I saw initially made me think I could by a decades worth of thermocouples before the ceramic sheath would pay off.

I got a 2 inch k type probe to replace the 4 inch probe from last year. It takes one inch to get past the insulation mat.

I'm also going to try a cooler location for the second PID thermocouple for the pump. The first one is in almost the hottest spot, in the view hole cover for the gasification chamber. The original end of fire sensor that failed, was at the end of the heat ex-changer. That is where I'm going to put the second probe. I can't put it in the chimney because of the extra air from the draft inducer dilutes the temperature.

I would be interested in the flue/water temp controller.

 

[Fred61]

I have the Ekoster 2 controller on my Eko 25 which has the ability to shut down the boiler based on water temperature.

Upon cold start the boiler fan will shut down if water jacket does not reach 70 in 30 minutes. After my longer batch burn or no fuel the fan will continue to run until boiler temperature falls to 70 and will continue to run for 30 minutes then shut down. I don't use the feature much since I'm determined to manually shut it down in order to save some charcoal for an easy light on the next fire. It has worked flawlessly for those times I could not be around or was called away during a burn or when I walked away from a fire lighting session before confirming I had a sustainable fire.

None of his interferes with my circ. launch temps. because I transferred that job away from the Ekoster to a Tekmar 156 and am using a circ. launch temperature of somewhere around 174. The features of the Tekmar including the differential feature allows the pumps to shut down without continuing to pump through while the boiler is cooling to that magic 70 number.

 

[jebatty]

Might 70C (158F) be quite a bit low? I regularly heat my storage up to 190F, and if the draft fan kept running it would actually work to cool down the boiler. I have my Tarm draft fan off at 100C, as I want it to shut down to leave a few coals to start the next fire and to make sure it doesn't cool down my system.

As for a ceramic sheath, a good idea. The Tarm has the sensor bulb in a steel tube at a top corner of the smoke box above the hx tubes. I have a separate K-type in the flue for a high temp draft fan shut down at about 550F. That sensor lasted 3 seasons before it quit working. At times when I added wood before the load burned down the draft would push the flue to as much as 700F.

 

[Fred61]

I agree. I think the 70C temp is fixed in the Ekoster. Not positive since the last time I visited it was when I set up the boiler 7 years ago. The long story is that the Ekoster only allows 80C maximum boiler temperature. I cheated by strategically placing the temp probe up into the insulation and placing the Tekmar sensor in it's place. Now the Ekoster is reading about 15F lower than the actual boiler temperature but I still can sense and read the temperature with the Tekmar.