My AHS S130 Coal Gun Is Sporting a New Percentage Timer

I finally got around to installing a "percentage timer" on my Coal Gun to initiate the fan periodically and (hopefully) improve my chimney draft for summer operation. Initial setting is for 2% "on" out of every 60 minutes. That translates to 1.2 minutes (72 seconds) of firing every hour. Later I may change it to 3% out of every 90 minutes, or to one of the other total of 960 repeat cycle choices this timer offers. Here is a quick snapshot:

Nice timer and a clean install.

For now, I would not extend the cycle beyond one hour. Experiment with 1, 1.5, and 2 minutes of "on" time and see what it does to flue and boiler temps. The idea is to burn long enough to get the coal "lively", but not enough to noticeably heat up the boiler.

Can you have it work every half hour?

mozz wrote:Can you have it work every half hour?

It works via two dials. The dial on the left is the one where you choose the overall interval of TIME through which it is to repeat cycle. This left dial is settable from mere seconds (beginning with 15 seconds) on up to 24 full hours. The dial on the right then determines the PERCENTAGE (selectable from zero to 100 percent) of the time selected via the left hand dial for which the device you have tied to the NO (normally open) terminal will be "on". Overall there are 960 different "repeat cycle times"/"percentages of on" that are selectable.

The short answer is therefore "yes". You can set the dial on the left to 30 minutes, and the dial on the right to "operate something" for any desired (and also available) percentage of 30 minutes ranging from zero to 100%.

This is off the top of my head, but I believe the left dial is selectable for 15 seconds, then 30 seconds, then 1 minute through 60 minutes (1 hour), then by whole hours up to 24 hours. The right hand dial is then selectable from 0% through 5% "on" in single percentage increments, then it jumps to 8%, 10%, 15%, 20%, 25%. 30%, 35%, 40%, 50%, 60%, 70%, 80%,90%, 100%.

The "percentage of on" cycle begins at the very beginning of any selected "time" cycle. One oddity that I have already discovered and well noted is that changing any of the dials on the fly while the power is still on automatically begins a new "percentage of on" cycle. Meaning that any changes to the dials trigger the immediate running of the fan in my instance. Also turning the power off and then back on again immediately runs the fan through an "on" cycle. It does not "remember" time (or time already accumulated) when the power is dropped, but rather it merely starts over (beginning with "on") when power is returned or restored to the timer.

Edit: This link is to a chart that gives you all of the 960 selectable time slices: http://www.nsiindustries.com/Repository/Files/EJW ... _Chart.pdf

Edit again: Note carefully that the chart has two pages!!!

So...how is it running so far?

Rob R. wrote:So...how is it running so far?

The fan is running for 72 seconds out of every hour, but that doesn't seem to alter the low draft picture by much. I'll know more when the mid-nineties return. I saw my manometer at (or perhaps a bit to the bad side of) zero when I returned home from work a day or two ago. That was when it was dead still, humid, and sweltering hot.

One time today I saw it at 0.005" before firing, and at 0.01" after 72 seconds of timer induced firing. A regular full fan cycle does a much better job of improving the draft. I have not heard it fire once today other than via the timer (but I wasn't home all day so who know if it fired on its own). I know it has not fired on its own since I installed the timer (which was right before I posted the picture). Full fan cycles seem to range from about 6 to 12 minutes.

I have never had much success with a timer cycle under 2 minutes. Coal just doesn't respond that fast. 2-2.5 minutes works well with efm's...might work for you too.

As I watched it (even a few times during the night) I noticed that rather than the boiler slowly and naturally cooling to where it fires (runs the fan) on its own, it slowly heated up to where it was sitting at 198 degrees just moments ago, having gained about 30 degrees over roughly a 12 hour span. I have therefore just changed the timer settings to 1% of 90 minutes (which will fire it for 54 seconds every 1.5 hours).

My initial gut feeling at this juncture is that the timer will probably be turned off before the day is out. By continually heating the boiler up it is not permitting the normal ashing cycle durations to take place and I'm very concerned that as a consequence the fire is potentially rising in the anthratube (which is bad because if it rises too high it will be burning in the hopper at some juncture). It also does not appear to be achieving my primary goal of increasing my draft. It further does not appear to be meeting its secondary objective of improving the situation of my partially to completely unburned coal in the ash pan with my particular batch of Blaschak. It appears that this repeat cycle timer endeavor may ultimately come down to being a solution without a problem for the AHS S130.

lsayre wrote:As I watched it (even a few times during the night) I noticed that rather than the boiler slowly and naturally cooling to where it fires (runs the fan) on its own, it slowly heated up to where it was sitting at 198 degrees just moments ago, having gained about 30 degrees over roughly a 12 hour span. I have therefore just changed the timer settings to 1% of 90 minutes (which will fire it for 54 seconds every 1.5 hours).

My initial gut feeling at this juncture is that the timer will probably be turned off before the day is out. By continually heating the boiler up it is not permitting the normal ashing cycle durations to take place and I'm very concerned that as a consequence the fire is potentially rising in the anthratube (which is bad because if it rises too high it will be burning in the hopper at some juncture). It also does not appear to be achieving my primary goal of increasing my draft. It is further does not appear to be meeting its secondary objective of improving the situation of my partially to completely unburned coal in the ash pan with my particular batch of Blaschak. It appears that this repeat cycle timer endeavor may ultimately come down to being a solution without a problem for the AHS S130.

First day with it, so give it a chance... if nothing else Larry it sure is a pretty ! I love that BX cable and I've never seen such a clean & spotless install (how old is that coalgun? did you do the install?) very nice!

dcrane wrote:First day with it, so give it a chance... if nothing else Larry it sure is a pretty ! I love that BX cable and I've never seen such a clean & spotless install (how old is that coalgun? did you do the install?) very nice!

Per the plate it was made in October of 2009. I believe it might have been a demo unit, or a floor model, or perhaps it was from an order that was placed and then canceled, and I got it at a nice discount when AHS was moving to their current location and selling off old inventory at their previous facility. I installed it myself and fired it up for the first time in October of 2011.

I have disconnected my timer. Experiment over. I was nearly 100% heading in that direction anyway due to none of my objectives for installing it having been met, but when it fired the boiler and then failed to shut the fan off at the end of the cycle time that was absolutely the last straw. Lucky I was there and watching it. Had I not been there the L4081B (high limit aquastat) would have gotten a good workout. As for the timer, perhaps the heat got to it? I just read where it is rated only for up to 122 degrees F. If you plan to use one, mount it remote.