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whole house rocket mass furnace

Posts: 3
Location: Pittsburgh, PA zone 6a
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I've been reading up on rocket mass stoves and furnaces for the past few months, and I have a basement remodeling project coming up, and I've been seriously considering putting one in my basement. Piping it to a chimney is a non issue as I have two currently unused chimneys that begin in the basement, they may need relined I'll have a qualified technician check that out, but that is a different topic. And there are many good plans for the rmh already. However I have been thinking about getting an 85 or 110 gallon salvage or overpack drum to cover the 55 gallon drum and attaching a blower or air handler to it so that I can push warm air through the existing duct work in my house. I'm wondering if anyone has ever tried this or has any thoughts on the implementation of this.

Fyi it is a large essentially unused basement that I will be turning a portion of into basically a 500 square foot studio apartment, and I intend to spend a fairly significant amount of time down there and I like fire, so tending the rmh should be a non issue.
Posts: 4154
Location: Northern New York Zone4-5 the OUTER 'RONDACs percip 36''
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Joseph Miller : Location, location, location, for the rest of the year we are asking people to go to the top of this page to the Permies toolbox, find and press > MY PROFILE and
at the next page ad your general location and local climate number if you know it ! This and more information on the final total are you Hope to heat with a Rocket Mass Heater
RMH, will help us answer you questions, as is you are getting two answers

A 6'' system with a 30 gal or 55 gal drum over the top as your heat exchanger is all that you are going to need, for the size of your apartment, However, counter-intuitively
if you had Two identical Rocket Mass Heaters one with a 30 gal drum on top and one with a 55 gal drum on top, Both of them would have to radiate the same minimum amount
of heat for the creation of the heat pump that pushes our hot exhaust gases 30' horizontally before exiting our Vertical final chimney! Because the smaller 30 gal barrel has less
surface area to radiate off of, it will radiate off the same minimum amount of heat energy as the 55 gal drum, but do it at a higher Temperature !

This is exactly the same effect as when your 3 yr old wants up in your lap they are such a good cuddle, with a smaller skin surface area to weight ratio, or mass to volume they
must radiate off the excess calories of respiration at a higher temp to maintain 98.6~ish

I am assuming that part of your utilities for the upstairs are in the basement, this should have its own ability to supply itself with 'make-up'air and your cellar apartment should
have its own ! Be aware of the BIG THREE what can cause you problems with smoke back into your basement from you Rocket Mass Heater RMH. Your Clothes Dryer is number
one trying to get your RMH to draft correctly while attempting to run your Clothes wryer is an exercise in frustration, fortunately during the whole of your heating season it makes
perfect sense to unhook your dryer vent from its out door connection and vent the heat and exhaust of the dryer into your living space as a way to 1) cut down on all fuels use
and to 2) keep more heat in the building 3) keep more moisture in the building which allows you to be comfortable at a lower Temp. After you have unhooked the dryer vent hose
and plugged the hole to the outside with temporary insulation you can use a pair of panty hose as a lint trap or buy a water trap, a commercial way to handle the common practice
of unhooking your dryer in winter ! this leaves the other two, which are similar but need a combination attack to solve, the fan in the Range Hood above your cook stove should
be a 2-3 speed fan and never run faster than the slowest speed during heating season ! The exhaust fan in your bathroom is a nice thing to have during times of summers 100%
humidity, it really should not be needed in winter a 2 -3 speed fan set to low is usually all that is needed here! If you have problems with the 2nd or third sinners I would add 5-10'
0n to my exterior chimney !

I am sorry I was confused by your saying you were trying to create a studio apartment ! See rule #1 location, also total number of square feet,then see the rest of the post below !
If your reason for placing an over pack barrel was solely to have a way to attach ductwork to blow hot at through you system,then You should be aware that you will need to supply
your improvised plenum with cold air returns to or pay to have a custom built plenum and a return cold air duct system put in, as the cold air is cooler and denser, the cold air
should be sized smaller, a small mistake in sizing air flow can result in an intractable whistling duct work every time the fan comes on !
joseph miller
Posts: 3
Location: Pittsburgh, PA zone 6a
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To answer the first, I live near Pittsburgh, PA zone 6a.

I'm not overly concerned with whether I have a 30 gal or 55 gal drum, nor with the temps of the drum surface. If I weren't planning on covering it with another drum and circulating air around it, I would most likely use the top to heat/cook soup, tea, or whatever.

I'm intending on hooking this to the main air ducts for the whole house, not just the basement. I hadn't considered that the clothes dryer would screw up the draft of an RMH however when I said that my chimneys were unused I had forgotten that one chimney does vent my hot water tank, and it has always drafted just fine. There is a CO detector nearby with an alphanumeric display that has never uttered a single blip. I'm sure that an RMH would create a stronger draft than what amounts to a slightly larger stove burner, but that is a moot point since as part of my basement remodel I'll be getting ride of that thing, maybe I'll build a semi-portable RMH out of it for a little outdoor warmth in the later months on the patio at my bar. Also I'd recommend asking if people are use gas or electric clothes dryers before recommeding that they be vented internally during the winter, some people are just incredibly dumb, my mother-in-law unknowingly tried to kill everyone in her entire house with that trick. Most people in my area happen to use gas, I'm the anomoly with an electric dryer. I haven't decided whether or not I'm going to put in a range hood, the only time I run the one upstairs is when I'm cooking something that creates a lot of smoke. Also I haven't decided on whether to put in an exhaust fan in the bathroom, the main bathroom hasn't had one since I moved in and we seem to get along just fine without it. The chimneys are ~25-30 feet in height and align pretty well with modern building codes for chimney height and placement in relation to the roof.

The RMH would be located close enough to the existing furnace and duct work that getting the thing hooked to the duct work shouldn't be a major issue. The mass bench would extend along a nearby wall.

Also I'm not unrealistic I don't expect that this would heat my entire house in a manner that would entirely satisfy me, haowever I do think that I may be able to put a nice dent in my home heating bill, especially since if I take a little bit of time here and there I can get about as much free wood as I could want, alternately wood is about $80 per cord stacked if I buy unseasoned wood during the spring, and since I have a dry unused detached garage that's made out of cinder block and poured concrete with decent air circulation, I'd say I have an OK place to let it dry out.

Any of this help?
allen lumley
Posts: 4154
Location: Northern New York Zone4-5 the OUTER 'RONDACs percip 36''
hugelkultur fungi books wofati solar woodworking
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Joseph Miller : We seem to be talking past each other, With all the appliances with fans, they are creating an area of high pressure on the Discharge side and low pressure
inside your house, this Will suck air into your house regardless of where the air comes from,the more we tighten up your house the more problems we get with a back-
drafting condition, My point is the Rocket Mass Heater is not only not immune to this condition, but is highly susceptible !

Please consider going to> www.makinghouseswork.cchrc.org/2013/what-is-stack-effect-and-how-does-it-affect-your-home/ While slightly more technical than your average
infomercial, if you watch the video with an open mind you will understand how a poorly latched attic ladder , or even a 2nd story window open can gravely affect your ability
to create a good draw in you basement ! Pay close attention at 5:50~ish !

Alternately, you can go to the Permies toolbox, select Search, and then on the next page enter "Stack effect'' in the search engine, and click on Google Search and do a
Permies- wide Search for that information !

If you are going to build a Plenum over the top of the RMHs Barrel, then any time you have a fire in your Rocket, you will have to flow air over the outside of your barrel,
regardless of whether your upstairs spaces are -'calling for heat'- or not, If the barrel is not cooled ether by convection or radiation, the temperature within the Heat Riser
will quickly match the temperature of the barrel, the system will stall, and with zero draft to carry your hot exhaust gases away down the length of your horizontal chimney,
your Feed Tube will become the only working chimney and fill first your Basement, and then your house with smoke !

Please understand that what you are suggesting has been proposed in these pages, and many others have set off to build working units Very similar to what you would like
to do ! If any of them have been successful at similar ''Damn the cost, I Am going to make this work !'' Project, they have been singularly reticent to come back here and
brag about their successful Builds ! - - I Know I would not be so shy ! For the Good of The Craft ! Big Al !
I have always wanted to have a neighbor just like you - Fred Rogers. Tiny ad:
Rocket Mass Heater Plans: Annex 6
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