leisure line 110 coal boiler dumping constantly

I can tell you what my setup is. I have not had my furnace dump for a while now. (also my first season with it)

First off I am burning buck, so rice is going to be different.

I have the aquastat set at 160 lo, 180 high and a diff of 10. The dump aquastat is set at 215. To help the aquastat read better I soldered together a deeper well and put some heat transfer compound down there. That helps a little bit with the dump aquastat reading the correct temperature.

I also just tap the pressure relief valve every time I fill the hopper since I have noticed air getting trapped in that chamber.

My timings are what I finally have down, this may seem low but I have on for 12 sec, off for 5 min, with the blower speed on medium and the feed rate all the way down.

I'm sure it will be different if you have rice.

The main thing I did was set the dump aquastat to 215. It won't trip until the boiler gets to about 220-225. But with the low idle timings it doesn't get that far up very often, even after a long call for heat and a bed full of coals.

Everything I said might be useless for you, but I hope it helps a little.

ok that might help me i burn buck also so i might try your settings mine seem to be to hot still also im running 36sec on and 10 min off and still to hot .

I tried running mine at your settings but it seemed to be to low. The other problem I had is after high fire it almosts goes out. Any thoughts.

Siff wrote:I can tell you what my setup is. I have not had my furnace dump for a while now. (also my first season with it)

First off I am burning buck, so rice is going to be different.

I have the aquastat set at 160 lo, 180 high and a diff of 10. The dump aquastat is set at 215. To help the aquastat read better I soldered together a deeper well and put some heat transfer compound down there. That helps a little bit with the dump aquastat reading the correct temperature.
I also just tap the pressure relief valve every time I fill the hopper since I have noticed air getting trapped in that chamber.

My timings are what I finally have down, this may seem low but I have on for 12 sec, off for 5 min, with the blower speed on medium and the feed rate all the way down.

I'm sure it will be different if you have rice.

The main thing I did was set the dump aquastat to 215. It won't trip until the boiler gets to about 220-225. But with the low idle timings it doesn't get that far up very often, even after a long call for heat and a bed full of coals.

Everything I said might be useless for you, but I hope it helps a little.

I have a similar problem, but I have a differential of ~25 degrees. Where did you get the heat transfer compound, is that a home store item?

No I don't have any compound my diff is dead on

I had the heat transfer compound left over from buying some computer parts. I'd assume that you can buy it at Radio Shack, but I know you can get stuff meant for computers online. Check amazon, they have nearly everything. Sometimes when you buy an aquastat they include a packet of it to put in the immersion well.

I've never had my fire go out with the 5 min off 12sec on. I like the shorter cycles rather than longer ones. I went from 12min off 1min on (I believe, it might have been 12min-2min) Any timing less then 12 sec on and it seems like the fan barely gets going before it is turned off.

When I did the 12 min / 1 min I would notice it raising the temperature a lot when there was a full bed of coals. With the lower setting of 5 min / 12 sec even with a full bed of coals the 12 sec doesn't raise the boiler temp a noticeable amount, which in turn helps it from dumping. When I picked up the unit I believe the recommended settings were 4 min/2min or 6 min/2 min. That was just way too much for me.

With the current settings I have a nice inch and a half of hot coal, even after 12+ hours of no heat call. Eventually the boiler temp goes so low that there needs to be a call for heat, which then gives a nice bed of coals again.

Summary: I believe short on cycles will keep the boiler temp from rising quickly when there is a full bed of coals, but it will also keep a nice inch or two of hot coals on the bed over long periods of no call for heat.

What's your reostat set at and how lo.g has your been running this way at those settings with mine on 12 arcs on and 5 min off it almost went out again. I think I might have to go to 12 sec on 4 min off

The stoker motor is at the slowest possible setting, the fan is half way ( dial is pointing straight towards the hopper). It sounds like you'll just have to do what I did, and constantly play around with the settings for 3 weeks or so. I would try to specifically monitor it after a call for heat ended, where no hot water was being used.

12 sec on, 4 min off sounds fine to me. I think I had it on that or a little bit but noticed that the bed of coals stayed about 2-3 inches, and I wanted 1-2 inches.

I like keeping the combustion fan at a little higher setting, I'm assuming it will keep the coals hotter. I really have no idea if it has any effect.

I've been running at these settings for 3 weeks now.

Ok thanks I will keep you updated on the outcome.

One last thing I forgot to ask what's your diff on h.igh limit differential

I have it at a 5 degree difference. If it does trip, by the time it reads the 5 degree difference its dumped the boiler down to like 100 degrees though. That's why I soldered together a deeper well for it, I was trying to get the sensor deeper into the boiler. tThe deeper well helped it read the current temp better, but its still just so high in the boiler, the water cools down so much before it reads the difference up top.

Right now it is set to 215, which means it will dump when the boiler temp reaches 220-225'ish. That is the only design "flaw" I see with the 110 boilers, the location of the high limit aquastat.

From what I've read from other posts, I think it is OK for the boiler to get that hot. Most of the boiler components (like the pump and bladder tank) say they can handle 240 degree water. If you have Pex stuff you might have a different story, but I am all copper and iron piping.

Another thought, looking back in your posts, I think my feed screw is only like 4-5 turns out while you said yours was 9 turns out. I adjust it when it is at a long call for heat so the coals are just an inch or two from the end of the grate. That might be a reason why the 5 min off 12 sec on works for me and not you.

Have you adjusted your feed rate? You might have already said that but I missed it.

Yeah my feed is set for an inch of ash at edge a full burn I think I need to give more coal though keeps going out from coal being all burnt up

Did you ever call Matt at LL and have him walk you through all the different adjustments? It seems like you are having an awful time controlling this boiler, and I sure hope there is a simple solution.

I've talked to him and guy that installed it and it just can't seem to be adjusted to find that sweet spot I had it run good for about 2 weeks then it would start going out with coal looking like it was burned up.