Cleaning the boiler tubes in a Greenwood model 300

I'm new to this forum, but am in my 6th heating season with a Greenwood model 300 outdoor wood burning boiler. It burns 1/4 cord of wood every 24 hours, and I presently use some scraper tools to try to keep the boiler tubes relatively clean while the furnace is hot. I would like to know if anyone knows of some sort of a wire wheel tool that will reach in about 4 feet that would do a better job of cleaning the tubes. Stihl makes a tree trimming tool that by removing the chain saw blade, might make a good platform for the wire wheel. Any ideas would be appreciated.

Thanks,

Dick

maple1 said:

Holy crap - that's almost 2 cords a week. That's crazy - what are you heating?

(Sorry, doesn't answer your cleaning question...)

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Ken,

We have a 6600 sq ft metal building (insulated with foam) and a 65 ft tunnel into a 5500 sq ft house with hydronic heat in the two story house. We go through 30 cords a season, and it is good exercise (heats us 4 times?). We are in mid Colorado at 7500 ft MSL and are burning excess biomass of juniper, pinion and ponderosa pine - not ideal.

Your tool idea is similar to one that I purchased from Greenwood with 3 balls on the end. It works OK when I clean during the off season and have one side of the boiler box open.
That way I can extend the rod in and clean between each pipe, then vacuum out the soot. I'm needing a better tool than I'm presently using to clean the boiler pipes from the front with the door open. What brand of boiler are you using? On mine there are two rows of pipes, one above the other with about 1.5 inches between each row. I'd love to see a picture.


Thanks,

Dick

Thanks TS, You are right. I have searched the web and found all kinds of cleaning tool for the insides of the pipe. One of the tools I built is about 6 feet long and allows me to turn a verticle Y looking tool to align with the tubes, then turn 90 degrees to scrape the underside of the top tubes. It will knock any soot and ash, but will not break down the hardened creosote coating the tubes. One has to be careful, because there is insulation blanket touching the tops of the top row of tubes.

Good luck with the state bird of Maine - the mosquito!

Dick

TS,

It is a half day ordeal every Fall, but I have it down OK. I will keep working on a wire wheel idea ... right now I have an idea to take 3 wire wheels - the two outside 6 " in diameter and the other 5 " in diameter and sandwich them together with the small one in the middle. That should brush the bottom and sides half way up the pipes.

Some time I would like to take the top off the furnace and place a piece of thin stainless steep sheet material right onto the top pipes, and then reinstall the insulation which I think would give a little better efficiency.

Best to you guys up in the North Country ... I landed at Lorring (?) AFB back in the early 70's. Are you near there?

Dick

TS,

It's a small world! I have many fond memories of layovers in Bangor, and my wife and I went to the Haystack Mountain School of Crafts to study blacksmithing back in the mid '90's - you live in a beautiful state! But then we love Colorado too....

I am also addicted to everything about cord wood....

Dick

Quincy,

That sounds like a great idea! I already have a rig like that, but didn't put the two together.

Could you elaborate on your storage facts?

The output from my GT300 goes first to a flat plate heat exchanger in the primary loop of a Munchkin 140 boiler. The two systems don't know each other exists. I consider the propane to be the primary heat source, so that if we drive off and let the wood boiler go out, the heating system carries on by itself. After the water leaves the heat exchanger, it goes out to our shop where we have a water air heat exchanger and the excess heat is blown into the 6600 sq ft shop, so the wood boiler always has a load. I tried to run the shop blower on a thermostat, but if you have no load on the wood boiler, the damper closes and it will soot up. Is that what you mean by a hot burn?

This year for the first time we are heating about 4000 sq ft of concrete floors, and in an effort to keep from burning much propane, I have reset the propane boiler to come on at 110 F, and set the mix valve on the secondary circuit (with 9 zone valves) to 100F. I call this LGH (Low Grade Heat), cuz the return temp from the floors is about 80F and the wood boiler is only returning about 150 -160 F water. I know I'm pushing the GT300 hard, but have found a happy medium to where the propane rarely cuts in. We could start a whole thread on how to regulate hydronic floors....

Do you take a side off your boiler each fall to clean the pipes? I find that there is a lot of soot at the back bottom of the unit which needs removing. I'd love to know if anyone has been able to put in a secondary air system for better combustion. After loading in wood, the boiler will chug for several minutes, which is unburned gases igniting. My 8 inch stack temp stays around 250-300 F, with almost no smoke after the initial 5 - 10 minutes.

Thanks for your input,

Dick

Snowman, Thanks for that brush idea! I will try it and let you know how it works on the bottom row of pipes. I may be able to shave it down to reach up into the second row of pipes.

Dick

Quincy said:

Hi Dick I heat a 1000gallon storage tank both the seton clone and the storage tank are in a detached shed.The tank and boiler are regulated by a differential temperature controller which starts the boiler circ pump when the boiler is 12 degrees hotter than the tank and stops circ when 2 degrees cooler .I burn full out to heat storage I do not get any creosote like I did before storage.I have the damper open only a half inch it seems to help with the puffing you speak of and I burn less wood.I cannot remove the side of my home built seton I clean it each year with a shop vac shoved in the exhaust vent of the seton and compressed air with the brake line attachment.The plumbing is in a primary secondary configuration I burn about 8-10 bush cords a year I feel storage was the best addition I made to the system much cleaner burns and frees me up a little not so tied to the boiler.Your stack temperatures are great ,mine at a good burn are about 450 -500 degrees .I do not have any water to water heat exchangers I run pressurized storage .hope this helps Quincey.

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Quincy,

I will definitely try limiting the draft and let you know how/if that works out in my situation. Also, please tell me more about the "brake line attachment" that you mention. Some sort of special nozzle? What temp do you bring the pressurized storage tank up to? How much pressure? I would have to add on to my 15 by 15 shed for a storage tank. Did you build the tank or purchase one?

We do something similar with an 8 panel solar hot water rig to heat domestic hot water, and eventually have it contribute to the house heating. We get 320 days a year of sunshine at 7500 ft, which makes that work quite well. We also generate about 10 KW with solar PV panels, and have a 5.5kw VAWT wind mill (we really don't have an ideal spot for wind).

Thanks,

Dick

Quincy, I do have a nozzle with about 4 feet of aluminum 1/8 inch tubing, and will try that.

How did you insulate the propane tank? I have a 1000 gallon propane tank buried in the ground.

Our solar collectors are drain down into a closed cell foam insulated concrete septic tank. The tank holds about 650 gallons of water, and since it is not closed perfectly I have to refill it with about 100 gallons every 3 - 4 months. Then we have 100 feet of 1 inch copper coil in the tank as a heat exchanger for the closed loop that brings the heat up to the house to an 80 gallon side arm water heater. We only have to turn the the closed loop on at 5m every day, for about 15 minutes, to bring the domestic water heater up to about 140 - 150 F. At our elevation, water boils at about 200F (7500ft). Makes bread making interesting, my wife says....

We are on the grid, with 3 tracking solar collectors and the wind mill which back feed a "net meter". We run some big welders, air compressors, etc occasionally, so being on the grid is nice. The problem is that if we loose the grid, all that equipment becomes "yard art", so this summer we added a battery bank and "grid/off grid" inverter, so that now if we loose the grid we have the option of cutting loose the grid, and having the inverter "trick" the others into thinking we have a grid so that we can feed limited items in the house/shop.

We are trying to get our electricity consumption down to 16KWH per year to just break even ... not there yet while we are under construction with the house.

Hope you didn't get too much snow up there this past weekend!

Dick