First time with a wood boiler. Home built stove needs a tune up.

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K_W

New Member
Dec 15, 2018
4
MI
I purchased a home this fall that included an outdoor wood boiler. The previous owner said it was a homemade unit (modeled after a central boiler) installed when the home was built, 14 years ago.

The boiler seems to be in great shape overall, but I could use some help fixing a few problems.

First, that gasket on the door is totally deteriorated. I found new gasket material in the basement. do i just tack it on with a high temp adhesive?

Second, there is a metal pipe sticking out through the roof to fill the water jacket. It had been previously capped with PVC, but it’s completely melted. There is also some sort of dipstick in the melted cap. Do I just replace it with a metal cap? Does it need to be vented? What’s with the dipstick?

Lastly, when I turn the unit on, there is some sort of actuator that opens and closes a baffle on the door. It doesn’t seem to close all of the way and makes an awful electrical buzzing noise you can hear all the way from the house. I assume that’s not normal, but what is the proper operation supposed to look like?
 

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Good Luck...
Hope you didn't pay extra for the wood fired water heater.
First your unit is not a boiler,boilers are pressurized.
Second unless you have prior experience with a wood fired water heater,i would abandon the unit.
Try to sell it if you can and start reading on here to learn about hydronic heating.After a few months then you should start to plan out a reliable working system that doesn't piss off the neighbors when you are heating your house.
If you have some wood fired heater experience then you can probably limp through the year,but expect using a bunch of wood and making a bunch of smoke.I am going to assume that the lines going to the house are questionable as well.
Did the PO give any indication of wood usage?Were you given any helpful info on the water heater?
I am going to say that there was an overheat situation that melted the cap.You can replace it with anything so long as it isn't sealed.The dipstick i imagine helps to check how much water to add.Being a water heater it is vented to the atmosphere and will evaporate water and require keeping the level up to prevent a overheat situation(melted pvc cap)
Door gasket...probably doesn't mater on that unit but high temp silicon will work for a while.Chances are the gasket was never though about when the door was built,so there is probably just a flat surface to put the gasket on.
The Central Boiler wasn't a good unit 14 years ago when it was copied.
If you have to limp through this year you will get the help you need to do that,but you should start planning on a replacement soon.And start putting up wood so if and when you get a replacement you will have the seasoned wood to use.
 
I have 0 experience with anything of this sort.

the house is backed up with a separate propane furnace, so I’ll be fine for the winter. The plumbing seems to be in good shape? It looks like 2 pex tubes run through a 6”-ish corrugated pipe filled with spray foam.

The previous owner said he had run it every winter right up until I purchased the house. According to him, 5-6 cords will get through the season.

I’ve put up a cord and a a half so far, and just built the covered storage next to the shed in the photo. Most homes in my area have some sort of outdoor wood burning unit to heat their home. What makes this one different than nicer looking name brand model down the road?
 
The fill pipe also acts as a overflow...the dipstick is to measure the water level...I would replace that plastic cap with metal....the "dipstick" appears to be a shotgun cleaning rod. You need to get someone out there who is familiar with these systems and get it checked out...no one here will be able to diagnose it properly with out running it.
 
Could I see some better pictures of the boiler up close. The damper door, the plumbing ports(if visible), the firebox interior and loading door. Anything that could give me a better understanding of what you're working with.
 
I’ve added a few photos, thanks.
 

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For your door gasket, make sure you have enough gasket to get around your door with a slight overlap. If you don't have enough get more. try to make it one piece. If you have enough scrap out all the old gasket and adhesive that might remain. Get some high temp RTV red silicone. I recommend the caulk tube size or a couple regular size tubes.

To reapply gasket, Run a decent sized bead of rtv all the way around the door. Put the new rope gasket onto the rtv and work your way around applying even pressure. Where the ends come together sort of goop the bunch of rtv on each end of the rope gasket then push them together. Now take a plastic grocery that's big enough to cover the whole door and shut it in the door to set the seal. You'll have to make sure the boiler is cooled down to not melt the plastic. Once the rtv is cured peel the plastic bag off and start your fire again.


For the cap on top, get a regular black iron or galvanized cap that is the same size as that pipe coming out. Drill a hole in the center about 1/4"-3/8" bigger than that rod that is coming out of it. Then install that into the pipe. YOU MUST DRILL THE HOLE IN IT. I don't want to scare you but Do not, under any circumstances, seal that boiler vent. As soon as it gets hot it will build pressure and first it will bulge out the flat sides of the water jacket and if the welds don't fail before it hits boiling point it will become a bomb. Flat sides do not take much pressure at all to bend. With it vented at all times it will be fine.


That thing that opens your damper door is an electric solenoid. And yes they can be loud. Basically the contacts are going bad in it. It doesn't hurt anything making that noise other than it's annoying. The one you have looks to be the same as the one I use on my fan damper. I'm guessing that your loading door gets hot and with that being mounted right to it with no heat sink it puts excess heat into it which will wear it out faster. They make alot of heat under normal operation.
 
The air damper should close completely when the boiler is over its high temperature limit and open up again when it drops below the limit. If the door doesn't close fully or sticks open and there is no heat demand in the house, the boiler will overheat. Since its not pressurized it will boil water and vent it as steam until it runs out of water or runs out of wood. At some point you will run it out of water, the steel will overheat and that will be the end of it. No insurance company will go near it.

I have no doubt that 1/2 the wood you would put in it would be wasted. The rest of the wood would go up the stack and out the air. If you have kids you will be contributing to their odds of their getting lung issues.
 
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I would be highly surprised if you could find an insurance company that would have anything to do with that water heater,let alone afford the premiums.
 
I would be highly surprised if you could find an insurance company that would have anything to do with that water heater,let alone afford the premiums.

Dude, he's looking for help, not fear mongering. His insurance company isn't going to give two craps about a wood burner not located in, or immediately adjacent to, his home. Give me a break.

Not everyone has the ability or need to invest in a downdraft gasser. We could at least try to be somewhat helpful.


K_W - I would not hesitate to burn that rig if you can fix the flapper (replace the solenoid?) and get a new vent cover installed. Don't be too terribly turned off by some of the comments here. Hearth.com can be pretty elitist when it comes to wood burning. Outdoor wood burner owners don't generally stick around for long. There are other forums more geared for those burners - give it a google. And good luck with your project!
 
@stee6043 I agree with you totally, we dont all have six figure incomes and this is a hobby thing so we can be self reliant or whatever, run what ya brung man, may not be the most efficient but beats paying the gas man a ton. @K_W feel free to PM me I run a homemade boiler and will help what I can, so will some others on here, they know who I mean.
 
I ran a homemade boiler like that for 3 years at my last house and I am in the process of building another. Make the flap close all the way and be sure to keep water in it and that is really all you need to do. Those solenoids always sound bad, as long as it pulls in don't worry about it.
 
Dude, he's looking for help, not fear mongering. His insurance company isn't going to give two craps about a wood burner not located in, or immediately adjacent to, his home. Give me a break.

Not everyone has the ability or need to invest in a downdraft gasser. We could at least try to be somewhat helpful.


K_W - I would not hesitate to burn that rig if you can fix the flapper (replace the solenoid?) and get a new vent cover installed. Don't be too terribly turned off by some of the comments here. Hearth.com can be pretty elitist when it comes to wood burning. Outdoor wood burner owners don't generally stick around for long. There are other forums more geared for those burners - give it a google. And good luck with your project!
That is what i am trying to do.
I don't have a big income 24K a year in Canadien dollars.
But i built my system myself,a lot of salvaged material,paid for the important stuff like boiler and flat plate heat exchanger ect.
I am voicing my opinion and helping.My opinion is just that my opinion
And i wouldn't bother with that unit even to heat my shop.
My opinion is if the OP is planing on keeping the house and insuring it he may as well get started looking at a healthy usable system.
 
@salecker most insurance companies in the US are not near as picky if the unit is not in a building, the only stipulation my company has is the building a wood burner is in wont be insured unless its a UL listed with proper install in a house. My Opinion, use what you got and take the money you save paying the gas man and save that to buy a new boiler, may take a while to get there but...
 
I'll second the insurance company issue. When I built my OWB I called my company first. They said they didn't care as long as the unit wasn't in a building that is covered under my policy. My boiler is in its owe little shed just big enough for the boiler, plumbing and insulation. Insurance won't cover the boiler itself but still covers my house and garage.

Think of it as an open fire pit. How many people have a fire pit? You really think their insurance dropped them because of it?
 
okay, thanks for all of the info guys.

I don’t want to start a new thread for a question like this but if I’m going to replace next year, where do I start looking? I’ll be heating 3,000 sqft and I’d like the option to run a second circuit if I build a detached garage.