OWB piping types

[ktm250rider]

We have just about decided on a boiler. Most likely going with a woodmaster. Just need to pick a size. We seem to be right in the middle of all the manufactures for sizes.
The woodmaster dealer around here sells the black corrugated pipe with "bubblewrap" foil insulation around the PEX pipe. He seems to be a one of the better dealers I have talked to. They even drop off an excavator as part of the purchase to dig the trench to the house. There doesnt seem to be any charge for this since they use the pricing right off the internet. I mentioned the urethane insulated piping and he said that the urethane breaks down from condensation and doesnt recommend it.
I cant find any information that PU foam will break down from moisture. It seems to be a great moisture barrier.

 

[rx7145]

Well I have the urethane insulated piping. I have 50 feet going from the shop to the house and 15 feet from the boiler to the shop. The first two years I had the boiler I just put the pipe on top of the ground. Even with 180* water on the lines it would take a day to melt the snow off the top. I never had any problems with condensation. Now it was pricy about $11 a foot. I had a friend go the cheap route (I'm not sure what he used) but a year later he was digging it back up.

Moral of the story: Don't get the chep stuff, The only person you cheat is yourself.

The "bubblewrap" foil insulation might be ok. I would just worry about water getting in. If the lines get wet they will loose heat. They must stay dry.

I would worry about condensation in the "bubblewrap" lines more because there is a air space that water could condence in even if no water leaked in.

Hope that helped.

 

[rx7145]

As far as size: Bigger is better!

I wish I had the bigger size.

 

[hockeypuck]

We have just about decided on a boiler. Most likely going with a woodmaster. Just need to pick a size. We seem to be right in the middle of all the manufactures for sizes.
The woodmaster dealer around here sells the black corrugated pipe with "bubblewrap" foil insulation around the PEX pipe. He seems to be a one of the better dealers I have talked to. They even drop off an excavator as part of the purchase to dig the trench to the house. There doesnt seem to be any charge for this since they use the pricing right off the internet. I mentioned the urethane insulated piping and he said that the urethane breaks down from condensation and doesnt recommend it.
I cant find any information that PU foam will break down from moisture. It seems to be a great moisture barrier.

I also have a wood master but I got my pipe from the local central boiler dealer. Do not buy the bubble wrap stuff, especially if you are putting it in wet ground. Spend the money on the good stuff. YOu will be glad you did. I hear many horror storys of people trying to heat up the surrounding water table because they used cheap pipe or installed it improperly. How exactly is a fully foamed pipe going to condensate?

 

[MS-310]

Look for microflex, it has pex-foam, the best out there. 10.50 foot

 

[blunt]

Never heard of OWB's ... how do they work?

 

[windthrown]

Never heard of OWB's ... how do they work?

Outdoor wood boilers. Basically they are a firebox surrounded by a water tank. Heat the water and pipe it to your house or greenhouse or garage or shop, and use a heat exchanger for space and water heating. You can look online at www.centralboiler.com for a good explaination.

 

[windthrown]

I mentioned the urethane insulated piping and he said that the urethane breaks down from condensation and doesnt recommend it.

Scratching head... I have never heard of the issue of condensation breakdown with polyurethane. It sounds like bull to me. UV maybe, but water contact? Methinks not.

I used PEX lines. One red for hot and blue for cold/return. They come in white and colored tints. I sleeved them wiht 3/4 inch foam insulation and then shoved the pair of them into 4 inch corrugated flexible black drain pipe. The idea is that you do not want the pipes coming into contact with ground water, which is the main thing that will rob heat. Keep the inside lines dry and away from the edges of the pipe, and they will be fine. This idea seems to have caught on, as I see this exact same stuff selling on Ebay now. That is the cheapest way that I could do the run to the house. It works fine. No problems after 2+ years.

 

[ericjeeper]

I made mine up myself

I shoved on armourflex un split , Each line is seperate Than I wrapped them together with the foil bubble wrap. Then I used a roll of shrinkwrap to hold it all together. Then I slid them into a 5 inch corregated field tile. Along with severa runs of wire. some 12-2wg and some 12 gage 3 wire (well pump wire) And I sent out a 3 pair of 18 gage for thermostat controls.
Whatever you do, I feel each line needs to be totally independent of the other. No sense in giving up heat on the way to the house by letting it rub off on the line going back to the boiler.

 

[ktm250rider]

Yeah Id rather deal with a little possible condensation than worrying about the water table.
I was wondering about the seperation thing as well. Most of the prebuilts are run right next to each other. This dealer said that his return line is still running hot so there shouldnt be much heat loss between the two lines. I dont remember the temps but he was saying his return line runs about 140 with an input of 170.

I couldnt find out where around here (NH) to get the microflex.

I did talk to a wood doctor dealer that has a new boiler coming out thats supposed to be EPA approved. Unfortuneatley, she says they have none to look at since they are all selling as soon as they are built. Theres no way Im spending close to 10 grand by just looking at pictures on the internet. Anyways, she sells all kinds of "bubble wrap" insulation but doesnt even recommend it for boilers. Pointed me towards Flexsul-seal which looks pretty promising.

 

[Butch(OH)]

I used the Urecon pipe as is sold by Woodmaster on their web site and highly recommend it. http://www.outdoorstovesupplies.com/Categories.bok?category=Insulation:Urecon+Insulated+PVC+Pipe
Like other good systems it is not cheap but as others have said how much ground do you want to heat? Mine is buried about 30" deep and last winter at no time could I tell where my pipes are buried due to thawing or snow melt. One other possible advantage is that I can pull my pipes without digging up the Urecon pipe. There is contact between the supply and return using this system but the heat taken from the supply is taken back to the boiler thus it is not lost as in ground loss. Believe me you will not have problems with heat delivery because of a little heat going back to the boiler, my model 4400 unit just idles to heat my house, shop and water but I am glad I went with it because of the extra fuel capacity as compared to a 3300.

 

[ghitch75]

here is what you want

http://www.cozyheat.net/logstor.htm

 

[MS-310]

Yeah Id rather deal with a little possible condensation than worrying about the water table.
I was wondering about the seperation thing as well. Most of the prebuilts are run right next to each other. This dealer said that his return line is still running hot so there shouldnt be much heat loss between the two lines. I dont remember the temps but he was saying his return line runs about 140 with an input of 170.

I couldnt find out where around here (NH) to get the microflex.

I did talk to a wood doctor dealer that has a new boiler coming out thats supposed to be EPA approved. Unfortuneatley, she says they have none to look at since they are all selling as soon as they are built. Theres no way Im spending close to 10 grand by just looking at pictures on the internet. Anyways, she sells all kinds of "bubble wrap" insulation but doesnt even recommend it for boilers. Pointed me towards Flexsul-seal which looks pretty promising.

My idea is----- if you dont have to pay shipping get what every type you can get....(not the bubble wrap) logstar, microflex, thermoflex....any of them will do....

 

[GRH]

Do it right the first time otherwise you will have to dig it up like I did. I built my house last year and trenched the lines in January. I was in hurry due the weather changing and put 1" pex line in their own individual 4" non-perf drain tile. I wrapped the pipes with 3/4" wall split foam. The supply line got a stone puncture in the drain tile and began to fill with ground water when the ground began to thaw in March. The whole tile got filled with water to the point where it ran into the house where I have the lines coming in. I also had a large thawed out area from the house to the boiler so I was burning wood to heat the ground. Fortunately my sump pump well is right below so no damage occured. I only use my OWB in the winter so I rented an excavator and dug up the lines in May. This time I over killed it and dug deeper and installed 4" perf pipe, tee'd it in the middle and trenched it to daylight. I ordered 20 ton of round 2's and covered the perf pipe with half of it. I again made my own individual supply and return lines but this time I installed non-split 1" wall armorflex over the Pex line. I also wrapped the outside with 2 wraps of 1/4" reflective foam that was leftover from my infloor system, I then ordered a 500' endless bag roll from McMaster Carr and slid each insulated pipe setup in that, then (barely) installed 4" non perf drain tile over that and then 2 more layers of endless bags over the tile. I shallowed up how deep I went with installing the tiles to 2' below the ground (on top of the round 2's) and backfilled the remainder of round 2's on top for coverage 2" above the top of the lines. Now there's only about 1' of earth on top and plenty of drainage. If this setup leaks I'm going to eat nails. Fortunately I am able to do this myself so all said and done it still only cost me $7/ft due to already having some materials on hand.

 

[rx7145]

here is what you want

http://www.cozyheat.net/logstor.htm

That's the good stuff. Man, it went up in price. Still worth it I think.

 

[ghitch75]

That's the good stuff. Man, it went up in price. Still worth it I think.

same stuff used for the past 5 years put in about 10 rolls of the stuff...i like it anyway

we sell it for $12.00 a foot

 

[blunt]

OWBs dont seem to have much of a foothold here in NZ. Some similair type boilers around but nothing quite like the OWB.

They look very cool

 

[windthrown]

OWBs dont seem to have much of a foothold here in NZ. Some similair type boilers around but nothing quite like the OWB.

They look very cool

Well heck, they actually work too! We put ours in 2 years ago, and shut off the house heater and water heater, and started saving like, $300+ a month from October through April. When we installed it I figured a 5 year payback. But they have jacked up electric rates here several times now, and now it is gonna pay for itself in about 4 years. That includes a nice near-new Stihl MS 361 chainsaw and the gas to run it to cut wood too. And we have to cut the trees here anyway to thin, clear snags, cean up windthrow and the like on this 100 acre wooded parcel. The wood is free... which helps a lot. And on top of that, we can keep the thermostat in the house at 70 F. or even 80 F. if we want. Before we were keeping it at 65 at night and 68 in the evening, and we were cold all the time. Also we have all the hot water we want all the time. A warmer comfort level is great to have, especially in winter months when it is cold and wet and miserable outside.