Print

[up_in_smoke]

Hello to all, I am looking for some feedback for designing my outdoor wood furnace system.

I recently began researching outdoor wood furnaces and through process of elimination ended up pulling the trigger on an Earth owb Mountain Man 505. It was a hard choice, found a lot of nice furnaces along the way but for my needs and budget this was the furnace for me.

I went through my local distributor who was helpful but I prefer a direct route. I don't like product that has changed hands several times that has incurred price mark ups along the way. I like saving money when I can and spending it where I need it.

I ordered my mountain man 505 with 4 (ports) outputs and 4 inputs, polar wrapped, etc. anything that could be factory done, I did... now I will take over from there. (The reason I didn't order the pumps or anything else is because I wanted to choose what I need, buy local (hopefully) from somewhere that when things hit the fan I know I can find a replacement part without delay?)

Also I had a competitor company come out. The price for their furnace was awesome but by the time they got done quoting my parts and install we went from $8,000 to $15,000. I know I can get parts and do the install myself for cheaper than $7,000. I even sent their estimate to other owb companies who were shocked on how high their quote was. This forced my decision to do it myself.

I attached a quick drawing on my thoughts so far...

I have the earth mountain man 505 plumbed with 4 output ports for:
     1) serve my barn
     2) serve my pool and spa (future use)
     3) serve my home (future use)
     4) spare

I plan on running 4 different loops, independent of each other
 My first run... what I need for this winter

Tomorrow I am setting a 5'x10'x6" concrete foundation myself for ($190) then from the owb I need to run 60' underground to my barn.
I need 1" supply, 1" return, 1/2" water fill line, and electric in the ditch (code requirements say separate electric and water but my well has both???) either way, i contracted someone to dig the ditch 4' deep x 1' wide x 60' long, ($500) i will put the plumbing down one side and electric down the other then the local spray foam guy said he would spray foam around the pipe ($500), I am thinking logstor brand pipe but I would like all 3 water lines in one? Anyone know where I can find this stuff in south-east michigan?

From the feed into the barn I get a little confused. My barn is 40'x40' overall and two stories. The upper level I do not plan on heating, however I am going to insulate it and allow the heat from the open parking area to escape into it. The owb is my primary and only form of heat for the barn. I do have a backup electric toe kick heater in the utility closet to keep the essential plumbing from freezing but thats it. Inside the barn I have a finished off 10' x 40' area that I plan on residing in while I build my house. The entire barn first floor has 10' ceilings and constructed of 2"x6" with spray foam all the way around (not yet, but soon it will). All the doors are also insulated and windows were the best I could afford.

Once the 1" supply enters the barn, I want a temperature gauge, then I plan on installing a 'main' run through the barn walls ending in the south/west corner of the barn where I plan on placing a hanging heater at the end of the supply.

From the hanging heater, I am going to install a 'main' return line paralleling the supply back out to the owb.

My thoughts is having a pump circulating the main line 24/7 and branching off of the main line with the components?

the fist component will be a 20 or 30 plate heat exchanger with mixing valve plumbed in for domestic hot water, i currently have a tankless h2o tank, so plumbing will be a bit tricky, any advice?, i want to heat my water with my owb first then have my electric h2o heater as a backup

next components will be 
6' baseboard heater
6' baseboard heater
15' baseboard heater
15' baseboard heater

installed around the inside of my living area, they will draw from the supply line and drain into the return line. I got advice from a pro that they should all be independently thermostated so that they cycle as needed to keep the heat even and reduce demand but I would prefer one thermostat, any advice?,

(I also think a water to air exchanger mounted elsewhere in the barn and ducted along the ceiling would be cheaper and easier to install then 4 baseboards... but what do i know, the pro told me to go baseboard because heat goes up?)

finally in the area designated for parking I want to install a large enough btu water to air wall hung unit to heat the 40x30x10 portion of the barn when I work on my cars, the rest of the time I will keep it at 50ish but having the ability to knock the chill out to change oil or brake pads would be awesome...

Im guessing the run from the owb through the barn and back with a +10% allowance will put me at a 350' loop. Any suggestions on a good pump?

also any advice and tips on what i should use, shouldn't use and what to run away from... i like shutoffs and isolation so when things go wrong its easier to fix, sharkbite connectors look great, i see 10' straight pipe at my local home depot which might save me from wrestling with a coil, any other tips?

[attachment deleted by admin for space issues]

[RSI]

With 350' and that heat load I would run 1-1/4" pex from the boiler for the main loop.
I Since you don't have a tank on the DHW I would use a 30 plate heat exchanger and put it in the main loop so water is always flowing through it.
All you will need to make it operate correctly with your existing water heater is to use a strap on aquastat on the OWB pipe that disables the electric water heater when the pipe is hot. You should be able to put it in series with the electric water heater.

For you zones (baseboard, etc) I would take the supply and return out/in at the same point in the main loop. (tees as close together as you can get them. Otherwise you will have some water flowing through when the pumps are off and also you won't loose flow to anything that would be between if you were to have them far apart.

[up_in_smoke]

from owb to point of entry on my barn... I have not seen 1 1/4 in the underground insulated jacket?

I talked to a local logstor rep whom stated he has the 2 pipe logstor in any length, pickup only, for 12.95 a foot.

or

Badger has a 1"/1"/3/4"/3/4" 5 wrap for 7.25 a foot, free delivery

I am not trying to go cheap, I would rather spend once than twice, I just don't want to waste money... if I only have 1" from owb to barn does it make since to step it up to 1 1/4" once inside or should i keep looking for 1 1/4" insulated underground?

[up_in_smoke]

also, if I pay the extra $ for logstar 2 line pipe, how should I run my 1/2" water supply line? I would prefer it be in the jacket to keep it from freezing?

[RSI]

Logstor is 26mm ID. The Badger pipe will be 1" CTS (copper tubing size, standard pex) unless you go with 1" pex-al-pex which is the same size as the Logstor. Those two are almost as big as 1-1/4" CTS pex.

As far as I know, there is no option with more than two lines with the spray foam type insulation.

There are other 4 and 5 wrap options available with 3 lines too.

[Scott7m]

1 1/4" insulated is common, even bigger sizes in logstor

[RSI]

Not really a good way to make sure it will never freeze where it comes out of the ground.

You could just put a tee inside into the boiler line and fill it that way. A little harder to see when to turn off the fill water but no freezing pipes to deal with. You could use a solenoid valve if you wanted and run wires out to the boiler if you want to be able to turn it on out there.

[willieG]

Not really a good way to make sure it will never freeze where it comes out of the ground.

You could just put a tee inside into the boiler line and fill it that way. A little harder to see when to turn off the fill water but no freezing pipes to deal with. You could use a solenoid valve if you wanted and run wires out to the boiler if you want to be able to turn it on out there.

this has to be about the best idea i have heard in a long time

[hondaracer2oo4]

I had my lines spray foamed in the ground. My run from the boiler to the house is 75 feet feeding my 24x24 water to air hx. With my calculations to have a 20 degree heat drop I had to run 2 one inch pex lines each way to reduce the friction loss enough to get the proper GPM. I payed $400 for 400 feet of 1 inch pex and I had a local spray foam guy come and spray foam the lines in the trench and spray foam the water tank on the boiler for $500. I lose 1-2 degrees from the boiler to the house. I am on my third season with no problems so far. I too have a T inside my house on the return line to the boiler that I use to fill my boiler. No need to run a line all the way outside just to fill the boiler, that is silly. You will get a good idea of how far down the boiler is on water and how long it takes to fill up really quick. I ussually wait until it gets down to a certain point, than I fill for 1 minute 30 seconds and I am good.

[up_in_smoke]

I had originally planned on filling with a 'T' from inside my home when I was going to go with brand x.

When I elected to go with the Earth unit things changed when I saw the video demonstrating how the 1/2" line fed into the rear of the unit - then once a day, you pull the handle on the front of the unit till water spews out, shut it off, then its good to go?

earth actually sells an underground pipe with (2) 1" pex, (1) 1/2" pex and electrical but a little research on it told me to keep shopping plus my local inspectors won't let the water & electric run together

But like RSI pointed out, its above ground, if the temp in the boiler drops thats prone to freeze?  I don't like that either...

This forum just saved me future $ and time...

I like the solenoid valve idea, bit over my head right now till i do a little research, i can't see the boiler from inside the barn so i have no idea when it would be full, id rather hit the switch on the outside and monitor the fill...

what kind of solenoid/wiring option do you recommend... i am set on the logstor piping now and like i read will either change it to a 1 1/4" standard pex inside or run the pex-al-pex for the same size fittings

with a 350' loop what size and brand pump do you recommend?





[attachment deleted by admin for space issues]

[cranman]

Don't know if all your future uses are going to be beyond the barn but if so you could take 2 sets of one inch that far and only use one for now. One inch isn't going to be enough for everything over that distance. If you run a garden hoose over to the back and use a filler tube from an automatic washing macine , you can hook up to the boiler drain in the lower left side of the picture and just close the valve when the boiler if full.

[RSI]

Asco red hat valves seem to be pretty good. They come in a lot of different voltage options. If you find a deal on one and isn't the voltage you want, all you need to do is get the right coil.

You may be able to use a zone valve also. (I haven't looked at the specs on the lately so not sure if they would be the best choice)
If you want to keep the cost down, a valve for lawn sprinkler system would even work. They are plastic though so if you use that I would put plenty of pipe between it and the boiler line so it doesn't ever get hot.

It seems odd you need to fill it every day. How often do they recommend adding treatment?

[up_in_smoke]

Today I poured my owb slab, I made it 5'x10' with a 2'x2' cavity to run my pipe through. I was going to sleeve it but just as I was prepping to go buy the pvc the concrete truck called and gave me the en route notice.

I got bids on the concrete ranging from $1,000 cash to $1,500. Outrageous, a little elbow grease, scrap wood, few pieces of re-bar and $190 to have a yard of concrete delivered and it's good to go.

I also ordered wood - seasoned mix. I got 2 cords split and 3 cords whole, delivered and stacked for $200. Hopefully I can begin harvesting free wood and allowing it to season for myself now.

The official measurement from the corner of my barn to the corner of my slab is 60' so I'm figuring 75' of outdoor piping will do just fine.

I talked to the only logstor dealer around here. He laughed and said nobody around here ever buys bigger then 1", just not practical. He can get it but it will be expensive, the fittings will be expensive and it will be a waste of money for the added 0.0? increase in pipe.

I also talked to a wood master stove rep, took him weeks to call me back, said he was busy lol. I told him I bought another stove and he got mad but offered his services in install supply at the cheapest rates I will find? Went on to talk about everybody spending their money on logstor only for it to become brittle after a few years. He will show me pieces that the lex pulls right out because the lex expanded and contracted squishing the foam. Said his 3 wrap will do the job, he can get me 5 wrap but will have to order more for the 75' I need?

What do you guys think about his logstor comment, possible or b.s.?

[slimjim]

Put yourself in his shoes, he's trying to make sales, come on you are obviously a frugal and do it yourself guy, read the past posts on here regarding pipe, you want it done right but are questioning the cost, my suggestion to you is don't cheap out on the pipe. I've been selling Logstor exclusivly for 10 years now and have never even heard of a failure in any way due to the pipe.

[up_in_smoke]

Last weekend I had a 4' deep ditch dug and installed my pipe from the cement pad to my barn.

I took the dual 1" logstor pipe, an insulated 3/4 pex fill line, 10/3 w ground underground cable and put it inside of a 6" solid corrugated pipe. I then slid the 6" pipe inside of a 6mil plastic sleeve to seal out the water.

I dropped it in the ditch, laid another empty 6" perforated pipe along side it and back filled it with about 8-10" of sand followed by dirt hoping the water will find its way to the empty pipe first.

My thought is I will have enough wire to run 2 circuits for pumps. I will have an exterior fill line and hose bib off the 3/4 line and the dual 1" for supply and return to my owb.

I took pictures I will get them up soon.

I heard from Earth today and my unit ships next week. So now I have to find a means of unloading the box from a semi trailer, any suggestions? My neighbors tractor can't handle the weight.