out door boiler installation with a slab house foundation any suggestions

[shmodaddy]

Hello guys newer to owb been around them but never installed one. My main question is what is the best way to enter my house that sits on a slab. My thoughts are to excavate down along the side then "tunnel" in a foot and come up thru the floor providing there is no footing. I am sure one of you have came across this before as I am sure I'm not the first to do this. Any suggestions very much appreciated!! Like I said this is the first instal for me so any help about any thing is great! I have been reading your forums and have found much advice . Thank-you very much

 

[Medman]

I have a slab that dates from the late 50's and is about 4 feet thick - the whole thing. I came up the side about a foot above grade and put in 90's through the wall. Then I built an insulated box around the whole thing, about 10" by 8" by 20" high. I had a friend cap it with white aluminum flashing to match the siding and trim. Not perfect, but the only option in my case. I put heat trace around the exposed pipes in case of freezing if I happen to be away for a while, but no problems so far. If you have the option to tunnel under the slab, go for it!

 

[shmodaddy]

Well that was a thought of mine also to 90 into the side of the house and box it in and insulate the hell out of it. And heat tape also.

 

[Tennman]

Our boiler barn is a slab. I had the advantage of pouring concrete around two, 6" corregated plastic drain pipes to provide my pex conduits into the barn. Had the barn's slab been already there, I would have done as you suggested. Dug under footer by hand far enough to go straight down thru the floor the old fashioned way with chisels or maybe coring saw. Hopefully someone else here can give you a less work intensive suggestion!

 

[rkusek]

Ditto on what others have said. I unfortunitely was not able to put any PVC pipes before floor on pole barn was poured. Since it was only 4" thick, I borrowed a core drill bit and and made a couple holes afterward about 12" inward. Packed it tight with dirt after the Pex lines were in place and sprayfoamed. I would still recommended circulating the water periodically if not continuously during extreme cold weather. I've been debating whether I should let mine run continuous again this winter, set up a method to make sure it cycles periodically when there is no call for heat, or take the chance that it won't freeze up. If it freezes up you're done for the winter so maybe 60W is no big deal. Not sure how much heat I lose by cycling continuous but it does greatly simplify things. I would try a test hole with a core saw to see how thick the slab is. You may have to build a chase like Medman, but is would be nice to avoid that.

 

[shmodaddy]

Thanks for everyone's advice. I plan on putting the boiler about 25- 30ft from the house on the east side due to space constraints. Plus main furnace ducting is right there along with hot domestic water. Any thoughts on my "plans" is greatly appreciated! Any "I wish I would've done this or that when I was setting up" are more than welcome also. Planning a bit of oversized concrete pad to allow plenty of working room plus lights for firing at night.

 

[[email protected]]

I recently completed installation of a Biomass 40 system. My house is slab on grade with an integral 12x18 in footer, and the boiler is housed in a slab on grade remote building located 100 ft from the house. I opted to tunnel under both slabs, which was the right decision for me. I cut 14 in squares in the slab with a concrete saw, and used a demolition hammer to knock out the concrete. I excavated the tunnel with a shovel and wrecking bar. All told, the project required 5 hours to complete.

 

[Sawyer]

I have photos of my chase construction on my Garn blog. I can not measure a degree of temperature drop between boiler and HX.

 

[bigburner]

done slabs a lot, usually, under most conditions, you can go under a rat wall footer or threw a frost wall footing [block is easy]. just punch a hole on the inside [good measuring is a must here] core bit, saw, hammer drill or just beat a hole with a sledge hammer. This is not as bad a job as it may appear, couple hours should get it done. Old fashion hard work. shovel and post whole diggers

 

[shmodaddy]

Ok guys its been a little bit but thought I would would update you all some on my project. Things moved a little slow for a while here at home as crops and field work was calling heavily but did go under the house and up through the slab as many of you suggested. Holy cow the concrete was 12" thick there. I used a hammer drill with a 1 1/4" bit to drill a center hole then half inch holes around that. Then JACKHAMMERD out. Phew! So I got my first warm up out of that heater. Did that on Fri 10-7 I had dug my trench with mini excavator Thursday night. On sat then I poured a pad to set boiler on. Today 10-16 I was finally able to place pex in the ditch and get covered with dirt. YAY! slowly getting there just not enough hours on the day.

 

[jebatty]

What are you reasons for using an OWB when you can eliminate the smoke and reduce your wood needs by 1/2 to 2/3 with a gasification boiler installed in a shed on a slab? I replaced my OWB with a Tarm gasifier in 2007 and could not be more pleased.

 

[shmodaddy]

The price was right on this boiler. And can't simply afford a new Gasser right now. Let alone all the storage issues. Its a used boiler that know well not some Cl problem child. Reading about your gassers I agree that they seem to be the way to go. Hopefully I can upgrade eventually. (Fingers crossed )

 

[jebatty]

Hope your project continues to go well. Plan for the future. Enjoy the present.

 

[shmodaddy]

Roger that!! The way I figure any wood heat is better than none.