LL AA-220 Max Draft Burn With Power Vent Please Help!

Let it go and go to the game!!! Let the boiler do what it does and enjoy life a bit.

Sounds like you're making some great progress!

When you are asking about zones and plumbing, here is what I have plumbed for my coal stoker and oil boiler as backup.

Maybe it can help you visualize what you can do so each boiler can be utilized as needed.

Zones are great at spreading out and staggering the demand of each load.

CoalisCoolxWarm wrote:Sounds like you're making some great progress!

When you are asking about zones and plumbing, here is what I have plumbed for my coal stoker and oil boiler as backup.

Maybe it can help you visualize what you can do so each boiler can be utilized as needed.

Zones are great at spreading out and staggering the demand of each load.

Did you have a pic? I can't figure out why this boiler is now doing the job I had intended, maybe it has a lot to do that's it's not sitting in sub freezing temps and that I quit messing with it? But hey, cannot complain! Think I going to take blrman's advice and just let it be for the season. It's now doing it's job which is all you can really ask. I can make some moves to improve efficiencies during the off season! I might get to do a little welding on that '77 Bronco yet! Actually wish my welder and car hoist was in the barn with the boiler now! It is staying beautiful in there!

Well I wasn't going to post anything today but I just got home and only had to put 3 bags in to fill up the hopper....#120 in last 24hrs and 21* outside with NE wind and boiler was in idle fire??? Doesn't make sense but I'll take it! I might end up liking this stuff yet! I plan to get to Lowes sometime today and buy a tube of that furnace cement and seal up the bottom of the burners as directed.

Dave, I have been running this week without the lid on the hopper.....Is there a reason I should put it on?

swyman wrote:Well I wasn't going to post anything today but I just got home and only had to put 3 bags in to fill up the hopper....#120 in last 24hrs and 21* outside with NE wind and boiler was in idle fire??? Doesn't make sense but I'll take it! I might end up liking this stuff yet! I plan to get to Lowes sometime today and buy a tube of that furnace cement and seal up the bottom of the burners as directed.

Dave, I have been running this week without the lid on the hopper.....Is there a reason I should put it on?

Uhhhhh if it's working my advise is leave it alone.

The boiler is doing exactly what it's supposed to do. It will modulate to match the load demand. If it's mostly idleing, you get a bonus by not burning a lot of coal when it's not needed. That is a MAJOR difference between wood boilers and a coal boiler. The wood boiler will roar and won't throttle down to idle that much without some problems with creosote and such. A coal boiler will go all the way down to barely keeping the coal lit.

Does Saturday morning see less hot water use than M-F?

That makes a huge differerenc whether you want to believe it or not.

I think he was hung up on the amount of POTENTIAL air he could blast into the coal bed. It took some time to realize he needed the CORRECT amount of air for the volume of coal on the beds. Open those things up and it would probably blow burning coal right out the PV. Sort of Kinda like a carburetor, the correct mix not just any old mix.

Kevin

Hello Swyman,

I am glad the LL220 boiler is working well for you now.

The Oatey furnace cement or RTV high temp caulk
in another example is a must to seal the stoker flanges
to the boiler shells.

Plan on buying several steel baskets for the ash so you
have them handy.

I bought 2 more yesterday to have on hand to let the ashes
cool before I bag them up to dispose of them.

lzaharis wrote:Hello Swyman,

I am glad the LL220 boiler is working well for you now.

The Oatey furnace cement or RTV high temp caulk
in another example is a must to seal the stoker flanges
to the boiler shells.

Plan on buying several steel baskets for the ash so you
have them handy.

I bought 2 more yesterday to have on hand to let the ashes
cool before I bag them up to dispose of them.

There is very little air that escapes there. There is no need to seal the bottoms of the grates. As he is learning less fingering the better as with anything mechanical.

The hopper lid should be installed , it is a good indicator of the overfire pressure being to little. If sweat forms under the lid then an adjustment will be needed. If no sweat most likely good.

swyman wrote:Did you have a pic?

Dang, forgot to attach the file!

Sorry, man, here's the pic of my diagram. It's an overview of the system.

swyman wrote:Well I wasn't going to post anything today but I just got home and only had to put 3 bags in to fill up the hopper....#120 in last 24hrs and 21* outside with NE wind and boiler was in idle fire??? Doesn't make sense but I'll take it! I might end up liking this stuff yet!

Most likely you have reached "critical mass" with your system and heat loads.

Coal stokers don't like "recovery" heating, they like "steady" heating. Once you've gotten enough heat into your zones that some are satisfied and don't need to such out every last BTU of the water that flows within 10 feet of it like a giant black hole...then BTUs can get to the next section and some might even make it back to the boiler, LOL.

That is one main advantage of proper zoning. Not only can you deliver Where and When you deliver BTUs to the exact place that is needed at any given time, you can control HOW MUCH heat (BTUs) go to a zone at any given time.

For example, say a given load is on a zone and needs to be heated by 20*. Well, you can either throw 'x' number of BTUs at it in an hour, or '1/2 x' over 2 hrs. Either way works, but what happens when your boiler can only make '3x' and you have 4 zones all calling for 'x'?

You are calling for X times 4 zones = 4x load, but the boiler can only make 3x, so each zone can LOSE heat and start increasing from X to 'X+1' then 'X+2', etc. You can see how the problem starts to snowball pretty rapidly over a few hours.

But if you have zones, they can all get their 1/2x max when all zones are calling for heat, then when the first (branch off the supply loop) is satisfied, the others can get 3/4X, then when the next is satisfied, the last gets a full X. It may only take 1/3x to maintain the zone after it us up to temp.

***

Now the above is NOT a perfect example. In reality the upstream zones usually get higher temp water, but the closely spaced tees like I've used help balance and limit excessive BTU draws per zone. That helps maintain a higher primary loop and boiler temp, which provides more heat to the zones and is less stress on the boiler.

But...zone "can" increase the recovery time of a zone. Hence the "steady heat" preference of a coal boiler. You don't have to heat the entire boiler and loop full of water before you can provide heat to the zones. Therefore, you can provide smaller amounts of heat over longer periods of time, which can result in a much lower average load- especially since "more zones" means even more of a chance of staggering the demand.

This is why many marginal capacity systems tend to spiral downward under extreme loads- like last year's multiple days of -30's. In a zoned system, you could "cheat" by prioritizing which zone needed heat "now", temporarily turn off the other zones, and crank up the aquastat on the boiler. Once that zone was satisfied, move to turn on the next one, and so on.

Eventually, that really cold scenario would result in lower zone max temps and end up in the same boat, but in most cases it can buy us up to a week. Most of those extreme temps don't last longer than that- or we can supplement with propane or whatever. Many (most?) of us have backup heat sources of propane, oil, wood, etc that can be called upon in those uncommon and extreme times.

Glad you are FINALLY getting some satisfactory HEAT out of your system! Hope the info I've posted is helpful for your next evolution.

blrman07 wrote:
Uhhhhh if it's working my advise is leave it alone.

.

That's exactly what I'm doing but I have to admit it's kinda boring! Only thing I have done the last 3 days now is dump the ash in the driveway every morning and top off the hopper. I'll have to tear it apart and clean it in about a week or two. Been doing a full cleanup every skid of coal as per instruction manual. I bought some 1 1/2" wire tube cleaners so I will be able to do a better job on those fire tubes!

McGiever wrote:Does Saturday morning see less hot water use than M-F?

That makes a huge differerenc whether you want to believe it or not.

Not really, my wife and I are the only ones who take a shower in the morning. I have 4 kids and they all take long showers at night after games or practice.

blrman....talking about small world. You know how I was just talking about going to the University of Michigan's Women's game on Sunday??? We sat right next to the coach today at my youngest daughters b-ball tourney. She had a daughter playing on the opposing team. Was pretty cool and she was very nice to talk to!

lzaharis wrote:Hello Swyman,

I am glad the LL220 boiler is working well for you now.

The Oatey furnace cement or RTV high temp caulk
in another example is a must to seal the stoker flanges
to the boiler shells.

Plan on buying several steel baskets for the ash so you
have them handy.

I bought 2 more yesterday to have on hand to let the ashes
cool before I bag them up to dispose of them.

You know I was thinking of buying a few of them but since now I park the Bobcat right in front of the boiler, I may just dump the ash in the bucket and take it out when it gets full? This is starting to go as I had planned it. We'll see how things go but if this keeps up I may not ever move it!

CoalisCoolxWarm wrote: Most likely you have reached "critical mass" with your system and heat loads.

Coal stokers don't like "recovery" heating, they like "steady" heating. Once you've gotten enough heat into your zones that some are satisfied and don't need to such out every last BTU of the water that flows within 10 feet of it like a giant black hole...then BTUs can get to the next section and some might even make it back to the boiler, LOL.

That is one main advantage of proper zoning. Not only can you deliver Where and When you deliver BTUs to the exact place that is needed at any given time, you can control HOW MUCH heat (BTUs) go to a zone at any given time.

For example, say a given load is on a zone and needs to be heated by 20*. Well, you can either throw 'x' number of BTUs at it in an hour, or '1/2 x' over 2 hrs. Either way works, but what happens when your boiler can only make '3x' and you have 4 zones all calling for 'x'?

You are calling for X times 4 zones = 4x load, but the boiler can only make 3x, so each zone can LOSE heat and start increasing from X to 'X+1' then 'X+2', etc. You can see how the problem starts to snowball pretty rapidly over a few hours.

But if you have zones, they can all get their 1/2x max when all zones are calling for heat, then when the first (branch off the supply loop) is satisfied, the others can get 3/4X, then when the next is satisfied, the last gets a full X. It may only take 1/3x to maintain the zone after it us up to temp.

***

Now the above is NOT a perfect example. In reality the upstream zones usually get higher temp water, but the closely spaced tees like I've used help balance and limit excessive BTU draws per zone. That helps maintain a higher primary loop and boiler temp, which provides more heat to the zones and is less stress on the boiler.

But...zone "can" increase the recovery time of a zone. Hence the "steady heat" preference of a coal boiler. You don't have to heat the entire boiler and loop full of water before you can provide heat to the zones. Therefore, you can provide smaller amounts of heat over longer periods of time, which can result in a much lower average load- especially since "more zones" means even more of a chance of staggering the demand.

This is why many marginal capacity systems tend to spiral downward under extreme loads- like last year's multiple days of -30's. In a zoned system, you could "cheat" by prioritizing which zone needed heat "now", temporarily turn off the other zones, and crank up the aquastat on the boiler. Once that zone was satisfied, move to turn on the next one, and so on.

Eventually, that really cold scenario would result in lower zone max temps and end up in the same boat, but in most cases it can buy us up to a week. Most of those extreme temps don't last longer than that- or we can supplement with propane or whatever. Many (most?) of us have backup heat sources of propane, oil, wood, etc that can be called upon in those uncommon and extreme times.

Glad you are FINALLY getting some satisfactory HEAT out of your system! Hope the info I've posted is helpful for your next evolution.

This makes perfect sense and the lack of multiple zones is what was killing me at first. I can't figure out why it is working so well now but I'm just going to keep it the way it as and get working on other projects!!!! Finally I am free from this! (pic below)