Hey, All, So, I've been wanting to get a OWB setup for a couple years now...its looking like that is going to happen for the next heating season. I'm in the thinking/researching stage right now. Any input is appreciated. This is going to be a long post, but I'm also using this as a place to organize my thoughts. I have a couple in-laws with OWB, but their setups are different animals than mine (radiant-in floor, water-air exchanger in forced air furnace). Current setup: 1,800ish sq ft ranch style house, full partially finished basement for another 1,400ish square feet. Many improvements made over the years to increase insulative properties. Hot water baseboard radiant panels (not the fin style) through the upstairs (10 total panels), 1 radiant panel in the basement laundry room, 4 cast iron radiators in the basement. Currently fired by a 200K BTU old-as-Alabama propane boiler system located about 1/3 of the way to the center of the basement (length-ways) and dead-center width-ways. Everything is on 1 zone right now, plumbed in with steel pipe, and a circulated by 1 B&G 100 series pump. Hot water comes off the boiler with 1 1/4" or 1 1/2" pipe to the far west end, T's, and steps down to 1" pipe to along the perimeter of the house to feed the panels, T's again in the far east end back to 1 pipe to return cold water to the boiler. This system is more than capable of maintaining ~100* inside/outside temperature differential, which is a lot more than I would need (I've never personally done it, but the previous owners were and elderly couple that kept it about 78* and said it could do it well below zero). Desired Setup: There are a few things I want to accomplish here: 1.) Remove all the iron pipe supply/return lines and replace with PEX. The current lines hang down from the basement ceiling about 12" for unknown reasons, I only have a 7' ceiling in the basement, and I'm 6'3". Do the math, duck or get a headache. 2.) Establish multiple zones. At a minimum the basement and upstairs need to be on separate zones. 3.) Keep the old boiler for back-up heat. Purely for back-up, I don't want/need to rely on it to carry and of the load for generating heat unless I have a catastrophic failure of the OWB. 4.) Thermal storage. I have plenty of room in the basement to add storage, however my options on getting a single big tank down there are somewhat limited. 5.) Move the wood and the mess outside (wife's request). I want a boiler outside the house, but it doesn't necessarily have to be a traditional "OWB". I'm open to building a boiler room in my current shop, or a highly insulated structure to hold only the boiler, storage, and some firewood. I'm not opposed to a OWB, but it doesn't have to be the only option. 6.) Make DHW during the heating season. Current propane water heater is getting expensive with my big family. The actual boiler I choose is only one part of the equation here. I know I need: Expansion tank Circulation pumps and/or zone valves DHW plate exchanger Heating system plate exchanger Drain/fill valves, isolation valves Air removal Insulated underground pipe Temperature gauges for various parts of the system Pressure gauge(s) Thermostat and zone/pump controller Probably more stuff I'm not thinking about right now or don't know that I need. Questions Should I run a "home-run" from a manifold setup to each radiator/panel? I've have considered going all-out and installing a wi-fi thermostat in each room to control each radiator individually, but that may be cost prohibitive (haven't researched yet). If I do go with storage, how should I extract that heat from storage? I see 2 options. First option would be to circulate the storage in the "open" part of the system and have a heat exchanger to the "closed" part of the system. Option 2 is to have the storage be part of the "closed" part of the system. What size plate exchanger should I get? I know I can go too small, but can I go too big? I plan on running 1/2" barrier PEX to each radiator. What size and what type of piping for everything else? What else? Right now I'm focused on everything else but the boiler...I'll research boilers later on in the process.
First, I am not an expert. -You could do a home run from each room, but that depends on your access or how much your willing to tear into everything to make the runs, it would make an impressive manifold wall completely split up. I personally would keep the current covered runs and just work on getting the head whackers hidden, instead of a thermostats, use TRV's and bypasses on each radiator, not sure if TRV's will work on the baseboard panels though. -I would keep the storage separate from the gas boiler, no need to heat that with gas. -Bigger is better? -From my reading, 1in pex is good to 100k btu so that is somewhat boiler dependent. Location of the boiler wind direction, underground run, Edit: Location of the boiler -wind direction, underground run, distance of run, proximity to wood storage, access to the boiler area(mud season) Things I'm thinking about if I do the same
You will benefit in many ways doing this. Free excess heat off the boiler for your shop, along with a much more enjoyable loading & maintenance "experience". Design in some wood storage and easy wood handling. Aren't "OWB's" open or non pressurized?
I'll give you a lengthy reply! LOL I have a stainless OWB and one advantage if you want it inside is you don't need to insulate. I made a 20' x 20' building but in hindsight a little bigger would be nicer. I like to get all my wood for the heating season in there. I do still but if was bigger it would be easier to move stuff around. of course that all depends on your heating demands. I'm heating a well insulated 36' x 50' 2 story farm house with full basement, 36' x 50' attached garage with 2 zones of radiant floor heat and all my hot water. Averages around 13 cord for 14 years of use now. 1st year with no insulation in the house was 29 cord! I used block on 3 sides with filled cores so easy stacking and no bug issues. Front is stick framed and screwed/bolted together so I can get the boiler out easy if needed. Door was made for easy loading and walking into the bed of a normal truck. My goal was to have it blend in so most won't even know it's there. Pipe is run underground into the basement under the new garage floor. You can see it coming in here on the middle right top(the 2 green pipes). I used smooth bore (hiQ) field tile so I can easily pull new lines if needed. Even layed 2 ropes in there. Can't stress enough to keep drainage arouind the pipe. I have a 4inch field tile under the line backfilled with pea gravel. You do NOT want water around it. When I installed mine, they did not have premade pipe. You just put the lines in with some split foam insulation. The stuff today is way better. When it enters it goes to the main pump you see near the floor. You need to have an expansion loop as mine is one the ceiling before it comes down. From the pump, it goes to the water heater. Simple side arm. I shut the valve off when heating season is done and switch the electric back on. Easy an trouble free. From there it goes to the lowest pipe to the zone valve for house heat. I have an hot water oil furnace with one thermostat. I run 7 plate heat exchanger. I kept that a quick easy install as well. Tied into the house line and it runs to the heat exchanger. When the house calls for heat, 3 way zone opens and exchanger works. Oil furnace pump runs 24/7 along with wood furnace pump. The oil furnace running constant keeps it quiet and the heat up and down is gradual. No tinging if you will. The 2 zones in the garage floor have their own pumps and thermostats. You can see them on the left (orange lines) and returns in the middle. from there it goes back to the boiler. A mistake I learned that I did was the heat exchanger is mounted wrong. It should be up and down as opposed to flat as I have it. Being flat will cause it to plug quicker I was told. I just replaced mine after 14 years. It was still working but couldn't keep up in extreme cold. I'm going to try to clean it out for a back up. Another thing I was not told to do was to install a strainer. I had an pump impeller(cartridge) die and they are plastic. Send the remains on into the system. I put one in now after the main pump. That leads to another suggestion. Put valves everywhere. I have a lot as you can see and it makes fixing things SO much nicer. You don't have to drain the system and priming/air in system is basically a non issue. I used all poly, brass, copper and stainless in the new system to keep corrosion issue low. I've added water one time in 14 years and a 1/2 gallon on corrosion inhibitor in all that time. A month ago my dealer hard tested my water and said it was borderline and to add the rest of the 1/2 gallon and he said it looked amazingly good. I attribute that to the materials used. For this reason I'd highly suggest to keep you systems separate like I did. This will allow you to fix you house system at a later time if you insist on updating. I would try it first to see if it will be okay to live with. The way I have mine, I still have the oil furnace as a backup if needed with basically work involved. Feel free to ask any questions. I am not a pro at this and don't claim to be. This was first install and I did it before I had any online help. My dealer was great, luckily. I would have killed to have what is available here now. Draw your whole system out so you can figure out the runs and sequence of things. This will make it look and perform better with lower costs. With an OWB there is no need for heat storage. The boiler is that. Unless you have a huge hot water loss from showers and such you can use a second water heater tank. Remember, your hot water will be 185 degrees so you will "water it down" via a tempering valve or mixer so you technically will have more storage there already.
Well, plans have changed a little. Going to do a phased approach and only install just enough stuff now to get it 'working', then go back in and replace all the radiant panel plumbing later. I just don't have the time to do both right now. We have some remodel plans that we're now 100% sure on that could cause quite a bit of rework if I did it now. Not a big deal for now. I'm fairly certain I'm going to get a Heatmaster GS200 boiler. Going to look at them again tonight most likely put in an order for one. Got my plate exchangers picked out as well as the main recirculating pump that goes on the boiler. I have an unused 22x25 slab of concrete that was used a long time ago for the patio next to an inground pool. The boiler will set on this slab and I'm 99% sure I'm going to put one of those metal carports on it to serve as my woodshed. Concrete will be nice to keep the mud situation to a minimum. I'll have to run about 30' of underground line to the house. I haven't picked this out yet. Still researching. Going to run direct burial wire and 2 runs of 3/4" schedule 80 conduit between the house and the boiler. I'm not sure if I'll ever need the conduit, but it won't hurt anything to have it there. I'm kinda torn on where to put the plate exchanger for the baseboards. I'm coming in on the far East end of the house...which is also the easiest place to cut in to the existing boiler return line. If I do it that way, my run to the DHW exchanger on the far West side is going to be extra long. I'll probably just do that since this is mostly going to be redone at a later date.
Lukem over at the "other" forum they have a good place for your questions. The Boiler Room - Wood Boilers and Furnaces I think they have an underground supply (insulated pipe) sticky along with some other good stuff although they were very snobbish about OWB's the last I followed them. That was a while ago. Hot water is hot water no matter how you make it and the info is still good.
I looked at some of that stuff. I don't have far to go compared to some installs, so I'm not going to worry about $...just want the best there is. I'll see what the boiler dealer carries. I'd like to buy local from him if possible.
Ordered the boiler tonight. It should be here in 4 weeks. Lots of prep work to do between now and then.
Got started on some of the prep work. Still a long way to go. 1.) Slab marked so I can notch it with a concrete saw to get the PEX lines up to the boiler. Going to try to cut it this weekend if my BIL brings his saw over. 2.) Got the tempering valve for DHW all ready to install, along with a bypass valves to the heat exchanger. Maybe get that knocked out this weekend too. 3.) 1" pex lines for the main loop in place and ready to tie into the heat exchangers when they get here. 4.) Power pulled over to the wall and ready to lay the direct burial wire. 5.) Removed paneling from basement wall, new studs and insulation, and plywood up on wall where my future "boiler room" will be. This is also where the lines from the boiler will come in the house. Still need to: 1.) Trench and lay underground PEX, power, and spare conduit. 2.) Plumb in heat exchangers. 3.) Drain existing boiler and create tie-in for heat exchanger. This is just temporary so I'm not going to get carried away. Just need to make it work. 4.) Install pump on boiler, connect underground lines. Seems like there should be more on the "still need to" list. What am I missing????
I decided I'm going to use ThermoPex for my underground lines. I like the idea of closed cell foam, but the freight on any other brand was cost prohibitive for the length I needed (35'). Got a call from my boiler dealer today and the delivery date was 4 weeks later than what we had hoped for, with a good chance of going beyond that. He was able to find a leftover 2017 model that's actually cheaper....and can be here in a week or 2. Time to hustle and get this done. Ideally this is done before bow season starts so I don't miss any time in the woods.
Did you paint the plywood where everything is going to be mounted? Awful frustrating once things are mounted, plus paint on lines looks half azzed If you do all the inside stuff now, it's all plug and play on the outside, which gives you more time with the dealer to pick their brains on everything else boiler related, instead of doing the little things while he's there doing the install. The heatmasters look really nice and have some good reviews elsewhere.
Got my slab notched...for some stupid reason it was 6" thick. Saw would only cut about 4.5" so I had to beat on it quite a bit. Got the old metal pipes in the boiler return line removed and ready to plumb in the new heat exchanger. Took two men, two 18" pipe wrenches, two 24" cheater bars, 47 cuss words, and 3 beers to get them out. Going plumb in the heat exchanger for DHW tonight if I can get off the couch.
