The small Econoburn gasifiers have no automatic shutdown when the unit is out of fuel so the combustion fan runs on forever or the owner notices and shuts it off. Everybody has their own way to overcome this using timers and temp sensors etc. Which way is simplest and best?
Econoburn out of fuel control
- Thread starter powerspec
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brenndatomu
Minister of Fire
Look in the "Everything Tundra" thread at the top of the main boiler room page, you will find in that 100+ pages, its there somewhere, (click the link below to go to a "glossary" of the thread) where some of us used a programmable temp control to override the damper when it got to a preprogrammed temp...you could do the same to shut off your blower...
maple1
Minister of Fire
I have a flu gas temp stat on my boiler that turns the boiler pump off and on. Did you ask Econoburn if they have a solution or suggestion? I would not want to have to live with that.
salecker
Minister of Fire
Could you elaborate on your flue gas temp stat? I am also wanting a shutoff 99% of the time i am at home when it needs to be shut off.I did fall asleep one night and the fan ran till morning.Probably pushed a bunch of BTU's out the flue that night.
maple1
Minister of Fire
It came with the boiler, which came from Smokeless Heat, so might be able to get there. I don't think there are any ID markings on it. But I can check next time I'm by it. Suspect it's Euro. Will try to maybe get a couple pics.
It's a pretty simple setup. Has a probe surface mounted on the smoke pipe just outside the boiler breach. Just an open/close switch, has a dial adjuster on the front to set it to desired setpoint. I also wired an A-B switching aquastat thru it with 3 strand wire - so if the flu stat doesn't start the pump, the aquatsat will when boiler temp gets up to its setpoint. If you are controlling a fan you'd want that to be running right from the get-go when everything is cold - so not sure exactly how you'd wire it in, it's not the same controlling principal, but there must be a way.
I've been running my 100 since 2009 and early on I didn't like the fact that the blower wouldn't shut off, so early on I modified mine with a TET612 also called JLD612 relay controller to sense flue temp to shut down the fan after the burn. A " K " thermocouple is mounted in the flue as it exits the boiler and tells the relay to shut down the blower. These gadgets are totally programmable so you set the temp where you want it to shut off whatever it is connected to. As you can see from the boiler photo , I actually have 2 of these mounted on my boiler as I added another one a few years back when I finally added storage to my system. This one controls my boiler to storage pump which shuts down after the burn is complete. These relays can be found on ebay or amazon for about $35 and have worked well for me all these years. You must purchase the thermocouple seperately.
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maple1
Minister of Fire
brenndatomu
Minister of Fire
I use a differential between the flue temp and boiler water temp. When the boiler is fired from a cold start this differential is timed out for 15 minutes, after that time the differential is watched, when the flue temp declines at end of burn to less than 10 degf above the boiler water temp it shuts the draft inducer off. This is done through a one shot logic and momentary button to start the inducer, timer to ignore the temp for 15 minutes and maths logic to watch the differential that opens the inducer contact at end of burn. This is all don in the Datafourth maq20 data aquasition system. I suspect it could be done on a basic plc from automation direct.
These relays are very programmable and I have mine set so that the blower needs a minimum of 180 degrees in the flue before it will activate , so I simply start a normal fire and watch the flue temp , when it reaches 200 degrees or better , I close it all up (doors and damper) and turn on the toggle for the blower and off she goes. At the end of the burn the flue temp must be down to 120 degrees to indicate the burn is actually done (and not simply idling ) and the blower deactivates.
Those controllers are easy to use. Can also be setup to be involved and complicated.
I use two to controllers automatically shut off the blower and pump/circulator like others.
There is a setting, called hysteresis, that has the on setting higher than the shutdown reading. It is user adjustable. Prevents short cycling among other things. Separates the on and off as much as you want. Break on fall here. Also adjustable.
So the temperature rises fast at boiler startup. It passes the hysteresis on/auto setting fast. At the end of burn, the slow fall of temps kicks in the lower off temperature.
On mine and maybe others, the PID controller can restart the "on" circuit if the temperatures rise after shutoff.
So for example the circulator can restart again once the blower is off and there are a few more coals than usual.
I use two to controllers automatically shut off the blower and pump/circulator like others.
There is a setting, called hysteresis, that has the on setting higher than the shutdown reading. It is user adjustable. Prevents short cycling among other things. Separates the on and off as much as you want. Break on fall here. Also adjustable.
So the temperature rises fast at boiler startup. It passes the hysteresis on/auto setting fast. At the end of burn, the slow fall of temps kicks in the lower off temperature.
On mine and maybe others, the PID controller can restart the "on" circuit if the temperatures rise after shutoff.
So for example the circulator can restart again once the blower is off and there are a few more coals than usual.
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