Wolf in Sheep's Clothing

When I test fired my AA130, I noticed my workshop was plenty warm. The AA is just like a radiator sitting there emitting heat. This would be ok if it were in the basement of my house, but in a remote building, there is no need to overheat the area.

So, I went to a industrial insulation supplier I know and purchased a 1/2 thick high temperature blanket insulation called Tempmat. Insulation is a labor intensive process.

1st you have to glue stick pins on the shell of the boiler. They make an adhesive for this but it is rated at 190 deg. F., so I used high temperature silcone. It doesn't hold as strong but works for thin insulation. Even with a sharp boxcutter knife, it is tough to cut the insulation cleanly. Note I did not insulate over the ASME stamp and model info.



Next you impale the insluation over this steel porcupine (yes, the pins are sharp). It is tough to stretch the insulation and not get wrinkles in it. There are cup push washers that retain the insulation. The pins are then cut off next to the washer. Gosh, sorta looks like sheep wool.



Then you adhere a fiberglass cloth mesh to the insulation with a insulation cement that is a paste consistancy (trowl grade). A second coat is required to ensure voids are filled and the mesh is firmly imbedded. This gives the insulation abrasion resistance.



Finally, you can coat the entire surface with latex paint. The color I had was blue - left over from painting a room. No sense in wasting it.


I got the boiler back together this weekend and got the coal bin filled. Now when I get some really cold weather, I will fire it up.

Not too neat of a job but should be effective. I have decided to keep my day job and not join the insulators union.

Steam up, I think you did a nice job. Looks good. Keep us posted on the temp difference in your shop.

I have seen some old boilers covered with asbestos insulation; it was probably installed in a similar manner. Looks like a time consuming job.

It would be great if you could do another 24 test to see how the reduced stand-by losses translates to coal savings.

markviii wrote:I have seen some old boilers covered with asbestos insulation; it was probably installed in a similar manner. Looks like a time consuming job.

It would be great if you could do another 24 test to see how the reduced stand-by losses translates to coal savings.

That test will have to wait until next spring when I can get to the auger in the coal bin to meter the coal. I must have moved about 7 tons into the bin as the coal up to the rafters now.

I hope it works our for you. I think during cold weather it'll work OK, but it'll be an interesting test to see how it works out if the weather is a bit warmer. Axeman Anderson offers a jacket from the factory, but they discovered that it just didn't work out. I was told the Axeman needs to lose a certain number of BTU's in order to stay going. If it does not lose the BTU's, then either A: it overheats, or B: it runs so little it won't keep a fire. That's why I say I think it'll be OK during cold weather, as then you'll be using the BTU's but during a warm spell, you may find it overheats.

Freddy wrote:I was told the Axeman needs to lose a certain number of BTU's in order to stay going. If it does not lose the BTU's, then either A: it overheats, or B: it runs so little it won't keep a fire. That's why I say I think it'll be OK during cold weather, as then you'll be using the BTU's but during a warm spell, you may find it overheats.

I think it depends on how well your chimney drafts, and the duration & frequency of your timer cycle. AHS provides an insulated jacket with their boilers, as does EFM. Some people have trouble with their boiler overheating in mild weather, others do not...which points me back to my original point, "it depends".

Freddy wrote:I hope it works our for you. I think during cold weather it'll work OK, but it'll be an interesting test to see how it works out if the weather is a bit warmer. Axeman Anderson offers a jacket from the factory, but they discovered that it just didn't work out. I was told the Axeman needs to lose a certain number of BTU's in order to stay going. If it does not lose the BTU's, then either A: it overheats, or B: it runs so little it won't keep a fire. That's why I say I think it'll be OK during cold weather, as then you'll be using the BTU's but during a warm spell, you may find it overheats.

If it doesn't work, you could do a dump zone, and loose all the heat you saved I think about insulating too, If I could run into some type of "blanket" that could be thrown over in the winter, and taken off in the summer if the fire dimishes. I have been running "good" all summer and it only ran on the timer for 1 minute every hour (unless we used hot water) and it always idles close to 180, I doubt it has bounced off the low limit on the triple all summer long, my ears tell me so

With proper design there is rarely a need for a dump zone. Let's use a very well insulated coal boiler as an example. Assume no demand. But heat production continues because "the keep the fire alive" mechanism keeps on producing heat. The water in the boiler is not circulated because there is no demand. It expands as it heats. Just size an expansion tank to accommodate the expansion. No dump zone needed. The size of the tank is reasonable because it only needs the accommodate the volume of water in the boiler, not the rest of the system water which is not expanding because it's at a much lower temperature.

You will need a dump zone if "the keep the fire alive" mechanism produces heat so rapidly that the resulting pressure is unreasonable. Remember at each demand for heat or domestic hot water the system is effectively reset. No BTUs are lost to a dump zone.

I should note here that the k-6 I have run for the last two years has an insulated jacket. I insulated the bypass piping for the same reason of keeping heat in the boiler and use it only when I need it. I noticed a small reduction in coal consumption after I did the insulation. The dump zone does not activate as far as I can tell. The only time it comes close is after a long hard fire and then the zones shut down satisfied. The boiler temperature creeps up as the coal fire dies down.

steamup where did you get the hard plastic insulation cover on the piping?

Larry

There are two major brand names of these fitting covers - Zeston and Proto

They are available through commercial insulation suppliers. They are also sold on the internet if you search for them.

They are in a variety of sized based on pipe size and insulation thickness.

http://www.knaufusa.com/products/commer ... overs.aspx

Yanche wrote:With proper design there is rarely a need for a dump zone. Let's use a very well insulated coal boiler as an example. Assume no demand. But heat production continues because "the keep the fire alive" mechanism keeps on producing heat. The water in the boiler is not circulated because there is no demand. It expands as it heats. Just size an expansion tank to accommodate the expansion. No dump zone needed. The size of the tank is reasonable because it only needs the accommodate the volume of water in the boiler, not the rest of the system water which is not expanding because it's at a much lower temperature.

You will need a dump zone if "the keep the fire alive" mechanism produces heat so rapidly that the resulting pressure is unreasonable. Remember at each demand for heat or domestic hot water the system is effectively reset. No BTUs are lost to a dump zone.

If their is a high limit like on mine set at 200, that the keep the fire alive timer will not bypass, if all the heat is stored (INSULATED), the times could miss a couble hours, or could go higher on the high limit, but what is the sence (mine idles near 180 with only 1 minute once an hour in the summer). I feel if it's going to loose heat any way, better to bleed it off where you want it(or don't), rather than the boiler room, the hotter the water is, the more btu's lost. I found my honeywell on ebay for $25 and a couple feet of wire, cheap dump zone, over the cost of any fuel.

I use a unispotter
http://www.google.com/products/catalog? ... CFMQ8wIwAg
To attach the studs

last job took a basement boiler room that ran at well over 100 degrees in January to a run temp of just above 80. This and several miles of 2 3 and 4 inch pipe insulation gave a pay back in under 3 years - plus the outlying zones worked far better, and the rooms were always at set point.