Underground PEX

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I don't currently have an OWB. I am using a add on wood furnace rated for 200 BTUs. It shares the existing duct work for the hot air oil fired furnace that has not fired in over a decade. I plan to convert to hydronic heat, with radiant floor on the first level, and cast rads on the second level. I will run feed lines to the attic and feed the second floor with legs from each rad. This house has been 65-70% remodeled on the interior, making it much easier to feed rads from the attic.

At this point I'm planing ahead of my schedule. Concrete pad, underground lines, then shed by June / July. I will be adding the boiler in the fall. The boiler shed will sit right where I process my firewood. It takes far to much of my time to process the wood, season it, then move it to the opposite side of the house where the bilco doors are to feed the indoor wood furnace. Not to mention this hot air duct system dates to the 50s and sucks. Total run from OWB to house is just under 150'. That is with a little length to spare, so I think my measurements were 141' including a couple feet into foundation and into shed.

I hope I'm painting a clear picture here.

After reading through the sticky thread, I have decided on the manufactured foam lines. I'll eat the cost up front once. 1-1/4" is my best bet.
You will have a totally different system than mine. The hydronic floor and radiators are closed systems and you will need to set up plate exchangers, mixing valves(most are 110-130 degree systems), manifold systems.

I want to go there eventually but the cost is around $16k to add that to my house. Much more even heat and more efficient in the end.

It would behoove you to have a professional HVAC person to design and tell you what to build. I will stick with my forced air until the remodeling happens in a few years.
 
You will have a totally different system than mine. The hydronic floor and radiators are closed systems and you will need to set up plate exchangers, mixing valves(most are 110-130 degree systems), manifold systems.

I want to go there eventually but the cost is around $16k to add that to my house. Much more even heat and more efficient in the end.

It would behoove you to have a professional HVAC person to design and tell you what to build. I will stick with my forced air until the remodeling happens in a few years.
I will have to have a system designed like you said. I'm trying to minimize my time and labor on feeding the indoor furnace by having an OWB at the wood pile. Even if I added a water to air HE at the oil furnace duct work and a stand alone water to air in the kitchen. There currently is no heat in the kitchen. With the indoor furnace, I have to prepare the wood, load it back into my truck again, drive it to the opposite side of house, throw as much through the bilco doors that will fit before jamming up the stairwell, go back in basement to transfer wood to other end at the furnace, and repeat. 4wks later, repeat the loading process.

For insurance reasons, I cannot have wood stoves until I pay off the house. That would have been my original solution. I would have added 2 stoves, and just run the furnace on the coldest days as supplement heat to the stoves. Where's the "bang head on brick wall" emoji?

Feeling a bit frustrated ..... 2nd winter here and the house hasn't been comfortably warm. Not to mention the parasites that live here with their hands held out.
 
Thinking a bit more ..... This forced air system has never been enough to heat this house from the start. The wood furnace was added in at a much later date to relieve the oil expenses. It has 2 water loops in the firebox that are not in use. I could add water storage and pull heat off of that to get it to the opposite end of house, that remains colder, and the kitchen with no heat. Kitchen was originally heated with a wood cook stove that the previous owner eliminated long before I got here. The duct for the kitchen heat was disconnected also. Even if I reconnected the one register, the room before the kitchen barely gets heat. Separate crawl space for the kitchen.
 
@Medic21 Great information. It seems like a lot of the OWB salesmen I’ve talked to over the last few months don’t know the nuts and bolts about hydronics. What you’ve spelled out is the nuts and bolts I’ve been looking for.

@all night moe what make model of OWB do you plan on getting ? Personally I’ve been thinking about getting a G4000 from Heatmaster.
 
For insurance reasons, I cannot have wood stoves until I pay off the house. That would have been my original solution. I would have added 2 stoves, and just run the furnace on the coldest days as supplement heat to the stoves.
You can have a wood furnace, but not a stove, WTH?! Who is your ins co? I'd get a new one...many ins companies have no problem with properly installed wood heaters...just charge $50 more per year for the privilege usually.
 
what make model of OWB do you plan on getting ? Personally I’ve been thinking about getting a G4000 from Heatmaster.
Home built gassifier. I've been studying them for a few years now.
 
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@Medic21 Great information. It seems like a lot of the OWB salesmen I’ve talked to over the last few months don’t know the nuts and bolts about hydronics. What you’ve spelled out is the nuts and bolts I’ve been looking for.

Most dealers sell, get their commission, and not give a chit after. Around here it’s just another product at a lawn and garden store or feed store.

We have a really good Heatmaster dealer here in Norther Indiana and an exceptional Crown dealer in southeast Michigan.

Find one that has support after the sale.
 
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The hydronic floor and radiators are closed systems and you will need to set up plate exchangers, mixing valves(most are 110-130 degree systems), manifold systems.
Revisiting this thread as I'm way behind my scheduled goals. Got hit in the pocket hard last year. The financial setbacks are still reverberating. Any reason, other than being 110-130* systems, that these should be closed loops?
 
You can’t run an OWB at those low of temps or you will have a premature failure.
Ahh, gotcha. I already understand that. It just wasn't clicking in my mind. I was thinking closed for oxygen barrier reasons.
Revisiting my other thread, This Old House, is also answering this. I'm overthinking things. The FPHEs will be worthy investments, to keep these radiant, closed loop, systems separate from touching the secondary loop, that I learned from you.

Thanks for all your help.