Coalpail.com Forum

Axeman AA130 anthrastat. Seemed the fire was burning a bit high, no fresh coal on top. Boiler is hardly running these days, timer only, maybe a bit in the mornings. Took out the 2 screws on the anthrastat cover and saw the adjustment was at 120ish. Cranked it back up to 140 with a allen wrench. I do seem to remember this happened once before and I know I had it set at 140. Vibrations causing it to slowly loose adjustment? Shall I take it out and see if I have a screw loose?

I have NEVER seen the adjustment move from vibration, or from any other source, EXCEPT a 1/8" Allen wrench. That is baffling, because most of the time, you never have to change the setting . I am anxious to hear more about this condition.......I have seen the ashing arm adjustable support loosen and move....even wear completely though, but not the anthrastat setting.

Could the ashing lever stop have moved on the arm, too?. Vibration would worry me, because there is none on any machine I've worked on unless the fan was going south
and had lost a piece/segments causing the imbalance. A dry bearing box could cause the bearing surfaces to take a dirt nap, but I know you check those.

How to calibrate your anthrastat ?I have moved the scale without using the Allen wrench! What setting for the summer for hot water ?

I think it's normal vibration from the motor running. Fan wasn't perfect when I rebuilt the unit. Just wondered if that's enough to change the setting if something in the bimetal or pointer is loose.
How I noticed it this time and last is like this........ Go down the cellar to check on sump pump or ashes or whatever. Boiler kicks on with the timer, I notice the ash solenoid isn't energized (which it normally is 95% of the time), fire is high up to the feed, half a bucket of ashes so I blow it off. I have been scrapping the bottom of the coal bin out and burning shovel fulls of fines and mud so I figured the high fire was from all the small fines.
Taking the screws out of the anthrastat cover shows the pointer at 120, it was exactly like this last time maybe 6 months ago when I saw a high fire. This was a factory anthrastat in the box I got with the unit, the original I thought was out of wack and just swapped them 2 or 3 years ago, so I have a spare I may have to calibrate with hot water. Pretty sure the adjustment is a type of threaded rod with some sort of tension locking on it, will have to dig the original one out and see.

Just to report some of my tinkering:

I've been experimenting w/ a digital controller w/ it's thermocouple clamped onto the Anthrastat's probe.
So far I have been just monitoring the digital read-out portion and haven't re-wired over to have the digital control to take over.

mozz wrote:Shall I take it out and see if I have a screw loose?

You're asking US if you have a screw loose? Oh, Man! That's a loaded & easily answered question!

OK... Kidding aside... When you adjust it using the Allen wrench, does it have some friction? Or does it move very easily? I'm thinking they have a certain level of friction.....if yours is looser "than normal" then maybe vibration effects it more than one that is "looser than normal". How long since it was adjusted last? Maybe check it once a week & see if it is slowly changing? Odd one for sure....let us know what you find?

Ok, swapped out to my old original unit. I guess I cracked the knob by over tightening the set screw was the reason why I switched to the new one. Anyway, the bad unit. Water warmed up to 130, turn the screw down first then slowly turned the allen screw clockwise and it switched on at 130. Now at 140, as I turned the screw up, it still switched on at 130. Also sometimes the meter would read 500 ohms when it switched on, other times 1 ohm. This tells me the large micro switch is going bad and has corroded contacts. Probably can't get that particular switch anywhere any longer, i'll have to take the unit apart and get the current ratings on it and see if I can make anything work. Might even have to drill out those tiny rivets and clean the contacts and put it back together, I have some miniature rivets here somewhere. Screw appeared rather tight and I don't see how any vibration could make it turn from 140 to 120, twice. Alzheimer's or senility or sleepwalking or mechanical failure are possible causes. Now the old original unit had a cracked knob so out to the junk box drawer shed garage to dig for a replacement. Old military pointer with brass insert with 2 set screw, this ain't gonna move. Drilled a hole for the allen wrench, works great. Set this one at 140 adjusted the knob, tightened the set screws, rechecked a few times, good to go.
And of course, wife is gone to Pittsburgh for 4 days and I decide to use the stove and just the same hour she is supposed to come home. So she walks in the door and sees wires hanging out of a pot of water and of course asks " What are you doing? " "Fixing the coal boiler" I say. "Oh".

O.K. Mozz, I will give you a hint when it comes to unpleasant incoming comments regarding any repair. You MUST deflect any criticizing of the dirty, dust making boiler itself. You should minimize the problem by pinning the blame on the small part that is the temporary difficulty. In your case it would go like this" No big deal here Honeybunch ,it is just this little switch that is a tiny bit out of adjustment. This type of thinking is very helpful for getting the heat Off while you are in the process of getting the real heat On. Mike

Thanks for the follow-up. Most EVERY knob I see on anthrastats is broken. Bakalite or whatever the material is is NOT tough. NOR is the round stud it is affixed to........a flat would have been nice.......Why aren't we all using an updated thermo-couple of some sort with a digital display.........

We are waiting for McGeiver to give us details.

Still tinkering, but it is sure nice to see a digital readout at a glance.
Sorta same as the Coal Guns.

I'm thinking something like this.
http://www.ebay.com/itm/PID-Digital-Temperature-C ... 35d5985e35
Need to get a piece of stainless tubing welded to a flat piece and try it out. Don't know if steel or copper would last when placed right into the ashes. Also have to find something that remembers its settings, the specs on these Chinese things don't tell you all.

I am working with that very setup right now......now for a datalogger. Still funny that you can just set a cumulitive repeat timer at 10 minutes for every hour the auger runs.....and it works quite well.

mozz wrote:I'm thinking something like this.
http://www.ebay.com/itm/PID-Digital-Temperature-C ... 35d5985e35
Need to get a piece of stainless tubing welded to a flat piece and try it out. Don't know if steel or copper would last when placed right into the ashes. Also have to find something that remembers its settings, the specs on these Chinese things don't tell you all.

That is perfect!!!

The SSR is a must for the inrush current of the ashing solenoid.
That is how AHS does it on their Coal Guns to.

I just leave the old Anthrastat probe in place and clamp the thermocouple junction tight close to the end. Doing this to replicate the same temp zone of the original.