RMH Cleaning: Seasonal Clean Out

[matt walker]

Well gang, I just went through my first major clean out of the RMH in my home since the install. I've used it as the sole source of heat for one full season and about half of the season before that. I expected to find some build up, but really wasn't sure how much to expect, or what it would consist of.

Today was the day. I took off the inspection cap for the clean out under the barrel first. There was a build up of incredibly light, almost so light you couldn't feel the stuff, black fluff right there at the cap. As I cleaned that up and reached back into the main flue path, under the barrel, I got into a little heavier fly ash. Light grey, with some dark speckles, this looked like what I expected. It was ash, and had no grit that I could discern. Also, no sticky residue or any indication of any creosote build up. It had built up quite a bit though, mostly on the bottom of the flue pipe. At this location it was probably 2" deep, so was starting to constrict the CSA a bit, although my heater was running great even up to the end of last season.

I used a shop vac, with the output routed through 20' of dust collection hose to outside. I have a 10' hose on the intake of the shop vac, so I was able to snake it around, up into the barrel, and the other way to the first T. It did a great job, blew a little light ash around the house, but not too bad considering. Made a BIG mess outside though, which needed hosing down and probably could use a pressure wash to really move it along.

Anyway, after that I proceeded to the first clean out, which showed me the long run from the end of the bench back to the 90 under the barrel. This one has about 1 1/2" of the fly ash on the bottom of the flue, with a buildup of the lighter black "fluff" all around the flue. Again, it was taking up some CSA, but nothing much. I was able to get the vac hose all the way back around the corner and get the flue totally clean. I had bought a 7" flue brush for this job, and used it because I had it to clean the black fluff off the sides/top of the pipe, but I don't think it was necessary. There wasn't much there.

Then to the last clean out at the end of the other bench. Again, light fly ash on the bottom and fluff all around. Now there was only 1" or so on the bottom, and I was able to get the vac hose back to the back corner to meet what I had done from the other side, and down the other flue to the bottom of the exhaust.

Overall, I'm exceptionally pleased, and relieved. I really didn't know what to expect, and in all honesty I thought it would be much worse, especially considering I hadn't done it last summer. The whole thing took about an hour, I made a bit of a mess, but less than I used to make cleaning the flue/chimney of the old box stove. Actually, as for dust in the house, it was pretty much on par with shoveling out the firebox monthly on the old smoke dragon box stove. I've got some photos I'll put up later. I'm really happy to share this report, this is something I've not seen much real dialog or photos of people getting inside these things after regular use.

[mannytheseacow]

As always, very valuable information Matt! It's great that you have so much experience to share with these heaters beyond just the build stage. Building just being the beginning, I know early on I was curious what it would be like actually fitting one into my life, and this is good info on how your RMH is performing that I haven't really seen anywhere else.

I can't wait to not be producing ash. I was never cold last winter, but I have a 6 gallon metal bucket that I filled with ash DAILY. I was burning primarily walnut and hackberry supplemented with a little oak and elm. The walnut and hackberry are great for long burns- I seriously lit a fire in October and kept it going through March- but gosh they produce a lot of ash! I'm sure my RMH performance will be a little different just based on the kind of wood I am burning in it. What have you been burning? Is there a dominant species?

I've got quite a shed full of wood split and ready for burn season this year. It's been cut well over a year and baking in the covered shed with semi-open sides for close to six months now, split. I'm excited to see how this stuff burns. Admittedly, I used to throw about anything into my potbelly with the hopes that the longer it burns, the better.

I imagine what you're burning in your heater is very relevant to the ash you are producing? Although the type of heater and combustion are certainly important, too!

Regardless, I have placed many cleanouts in my RMH and plan to monitor ash regularly and clean when necessary, just so I can sleep well at night! I've had a few very small burns and so far I'm not really seeing anything at all, but I'm looking forward to some cool weather when I can fire it up and let it burn for a good long time.

[matt walker]

[matt walker]

OH! I just have to add, DON'T VACUUM YOUR HEATER UNLESS YOU RUN THE EXHAUST OF THE VACUUM OUTSIDE! Sorry to yell, but holy cow, I can't believe the mess out doors. If I had fired up the vacuum inside and started going for it, I probably would have just sat down and cried. This stuff is so fine, so black, so invasive, I think you would absolutely destroy your living space if you accidentally blew it all over inside. Just had to add this in case I wasn't clear above. I can just see myself not ever having done this, scanning a thread like this and just being all "Cool! Just vacuum it out. I can do that!." Then proceeding to wreck the house.

[pa_friendly_guy]

Good Job Matt. I am glad you thought to run the exhaust outside. That could have been one of those Learning Experiences if you hadn't. It really didn't look too bad in there after burning green hemlock and pine for over a year. There really is very little smoke from these heaters. That is one of their best features in my opinion.

[Oddmar]

Next time Matt, just pop off the caps, run your cleaning brush through to knock all the gunk loose, re-cap the cleanouts, then put a gas-powered leaf blower down the feed chamber. That should blow it right out...

Or do the brush thing, put bricks over the cleanout caps, then squirt a little kerosene into the cold burn tunnel. Wait a few minutes for fumes to fill the drum, then light a match and throw it into the feed chamber. Might be a good idea to put a paving block over most of the feed chamber opening to reduce blow-back. And maybe wedge a 2x4 between the drum top and the ceiling. And stuff the oven area with an old bedsheet. Possibly sitting a block on the cast-iron heating area would be good too. But i'm sure it would work.......

This recipe is provided for informational purposes only. No similarity to persons living, dead, (or undead) should be inferred.

[pa_friendly_guy]

I'd pay money to see you use the kerosene thing and wait for the explosion Matt. I don't see what could possibly go wrong. Putting a 2 X 4 on the top of the barrel wedged against the ceiling is probably a good idea though. When it explodes it won't take of like a Rocket.