Home made boiler, new at posting here

[Chainsaw_Maniac]

I am planning on having my circulator pump running all the time (most new circulators have 3 speeds) since I will have a storage tank and a heat exchanger to my home pressurized propane boiler. I think the inside of the firebox (from firebrick to firebrick and top of combustion firebrick) is 27" wide by 26" deep by 22" high (to the top of the top firebrick).

I have been thinking about a secondary fuel source (ex. an oil boiler) heating the same set of rads as the wood boiler. I'm still go with the thermostat though. The reason is that the propane or oil boiler wouldn't be running all day and I'd just be circulating relatively cold water, wasting electricity and making noise.

 

[Chainsaw_Maniac]

........His system holds so much water, there was concern about expansion. I have heard: for every 55 gal of water, it will expand 1 gal when at full temp.......

Yeah. A relief valve is a must on any bioler system. Mine is just a copper pipe that would release the water into the basement. It's set just before the boiling point at a pressure that would ensure my pipes don't burst.

 

[leon]

boiler

About your boiler;

In my past experience the half bricks do not stay in one piece and will crack.

I have had a smurf with a flame thrower blowing a foot long flame out of my
bottom draft/ash pit door so keep that in mind.

The other thing is the entire interior should be lined with firebrick to absorb
and release heat into the firebox and water jacket. you can use angle iron
welded to the walls and floor to hold the firebricks in place and also allow the firebrick
and boiler walss to expand and contract properly.


My firebox is filled half full with firebrick using a piece of 12 by 12 channel iron covering
half the depth of the firebox and coal grates and I wish I had done this 28 years ago.

I think after a while you will really want to line the firebox with full firebrick using angle iron
to hold it in place and allow for expansion and contraction as the half bricks wil crack due to the
drilled holes and thier being thinner from my experience.

 

[feader72]

Just a question, but why only 80 gallons of fluid? I know different size OWBs use various size tanks, but 80 gallons seems small. Of course, I don't have a degree in thermal transfer differential between different materials, I did stay at a Holiday Inn Express last night.:msp_tongue:

Shea

hahaha that was funny sir, yes the boiler holds about 85 gallons plus I have a storage tank which is 80 gallons, for a total of 160 gallons. There are lots of pros and cons with how much storage to have but on the boiler side, hopefully it wont take long to heat 80 gallons i.e. fast recovery but Im not sure having so much storage capacity would do me any good when the circulator pump is continuosly running?? could be wrong, im open to more suggestions.

 

[feader72]

Yeah. A relief valve is a must on any bioler system. Mine is just a copper pipe that would release the water into the basement. It's set just before the boiling point at a pressure that would ensure my pipes don't burst.

No I wont have any relief valve because the boiler is non pressurized, it has a gravity fed expansion tank, its totally open with just circulation pressure, which i imagine wouldnt mount to much

 

[leon]

hahaha that was funny sir, yes the boiler holds about 85 gallons plus I have a storage tank which is 80 gallons, for a total of 160 gallons. There are lots of pros and cons with how much storage to have but on the boiler side, hopefully it wont take long to heat 80 gallons i.e. fast recovery but Im not sure having so much storage capacity would do me any good when the circulator pump is continuosly running?? could be wrong, im open to more suggestions.

The more thermal mass being water or firebrick you have allows you to retain heat and give off heat to the water supply feeding the heating system.
The converted to water UUUUGGGHHH!!!!, steam radiators are also a great way to store and retain heat in a home IF AND ONLY IF it is well insulated and or the radiators are away from the windows of the home and along the interior walls.

 

[tooold]

The systems I have seen have both a pressure relief and a expansion tank.

 

[leon]

No I wont have any relief valve because the boiler is non pressurized, it has a gravity fed expansion tank, its totally open with just circulation pressure, which i imagine wouldnt mount to much

Your going to need a low pressure cap or elbow with a screen to
reduce /condensate/steaming vapors from escaping as well.

 

[feader72]

Without air supply for the grate area, I think you are going to have a dead firebox. My Country wood stove has similar secondary burn tubes but also has the main draft that brings preheated air in above the door. The air washes down across the glass, then goes into the grate area at the bottom creating a swirl action in the chamber. My stove will NOT burn just using the secondary tubes for air. A different woodstove design brought air in the back 2 lower corners, through the grate area, up across the iron doors, through the top area and out the pipe. The neighbors shop stove brings air up through the grate area through holes. It works until they plug with ash so he burns with the door open. My point is you want your fresh air where it counts...down where the fuel is...the grate area.

Sir, I fully understand where you are coming from and I had the same thoughts, but look at it this way, its basically the same thing. The main draft gets heated via the sides or however and then the air gets sucked (draft downwards) to the fire, so why then wont the fire just suck air from the first 2 of my upper secondary tubes downward?? Thats where Im confused too, but again I wont know until I try to fire it, the problem is there will be no effective way to view it since I dont have glass door. My neighbor has an epa woodstove with those upper air tubes and when I follow his intake air it goes like this : intake air goes around the sides where the tubes connect to and then continues to air wash for the door which also helps provide primary air but its still the same air feed. Any other thoughts sir? Maybe I should also drill a big hole in the top of the air tube to allow for the "air wash" downward to the primary combustion.

 

[feader72]

About your boiler;

In my past experience the half bricks do not stay in one piece and will crack.

I have had a smurf with a flame thrower blowing a foot long flame out of my
bottom draft/ash pit door so keep that in mind.

The other thing is the entire interior should be lined with firebrick to absorb
and release heat into the firebox and water jacket. you can use angle iron
welded to the walls and floor to hold the firebricks in place and also allow the firebrick
and boiler walss to expand and contract properly.


My firebox is filled half full with firebrick using a piece of 12 by 12 channel iron covering
half the depth of the firebox and coal grates and I wish I had done this 28 years ago.

I think after a while you will really want to line the firebox with full firebrick using angle iron
to hold it in place and allow for expansion and contraction as the half bricks wil crack due to the
drilled holes and thier being thinner from my experience.

sir, thanks for the input, but my pictures do show I have metal strap and bolts which hold the bricks in place on the sides, the pictures I provided show that some firebrick is missing on the sides, this is because I ran out and had to wait to get more but they are now finished so the whole fire area (grate, logs and tubes etc) are surrounded by firebrick. The strapping holds the brick tight, if they crack Im not too worried as long as they dont fall down / collapse. the upper (top) firebrick are held in place by t angle iron 3/8" thick.

 

[feader72]

one more pic

Ok this last picture, is when the boiler was installed in the "shack". My wife named the boiler "spongebob" because is a big yellow square hahaha (the insulation is not pretty but its meant to be fuctional).

If you look real close at the shack you can see the gravity fed expansion tank in place, its an old 100# propane tank that I modified, cut up etc. Please note : I dont know that I would use a propane tank again, not because if the initial hazards but because of the smell, thats right, they stink to high holy heck. I first took off the valve on top to let the tank air for a few days, then I drained the oil (just let it come out on my garage floor and used some oil sorbent to pick it up) it wasnt much oil but omg even after i got rid of the oil sorbent, it still stunk up my whole garage, worse part was some of the oil got on my work clothes and the smell just made me sick. Anyways, then I filled the tank with water and let it sit for a day to get into the pores etc. Then emptied it, stood away from it and tested that all fumes were gone with a cutting torch, it was good to go.

now when its time to fill the boiler with wood, we can just say "go feed spongebob" hahaha :smile2:View attachment 211633

 

[huntindog1]

Hello and good job, you need a baffle plate up above your secondary air tubes and on top of the baffle plate you need some kind of high temp insulation like ceramic fiber , short term fix for a insulation layer on top of the baffle plate is take fiberglass insulation and take the backing off then rap the insulation in some super heavy duty aluminum foil.

Or better yet lay fire brick up on top of your baffle plate then lay the insulation on top of it.

The baffle plate should sit just on top of the 2ndary air tubes and seal at the back of the stove and sides so the smoke has to go up and curve around the plate not escape around the sides or back .

Plate should come foward about 2/3rds the way towards the front of stove so 1/3 is left for smoke to escape.

lastly put some kind of small viewing window just big enough to see if secondary burn is happening.

 

[feader72]

Hello and good job, you need a baffle plate up above your secondary air tubes and on top of the baffle plate you need some kind of high temp insulation like ceramic fiber , short term fix for a insulation layer on top of the baffle plate is take fiberglass insulation and take the backing off then rap the insulation in some super heavy duty aluminum foil.

Or better yet lay fire brick up on top of your baffle plate then lay the insulation on top of it.

The baffle plate should sit just on top of the 2ndary air tubes and seal at the back of the stove and sides so the smoke has to go up and curve around the plate not escape around the sides or back .

Plate should come foward about 2/3rds the way towards the front of stove so 1/3 is left for smoke to escape.

lastly put some kind of small viewing window just big enough to see if secondary burn is happening.

Sir thanks, but I already have firebrick on top (which is what I think you are referring to about the baffle plate, its just firebrick) I believe I posted apic of it already but Ill include it in this reply in hopes that I get what you are referring to.
pic : View attachment 211635View attachment 211636View attachment 211637

 

[benp]

Ok this last picture, is when the boiler was installed in the "shack". My wife named the boiler "spongebob" because is a big yellow square hahaha (the insulation is not pretty but its meant to be fuctional).

If you look real close at the shack you can see the gravity fed expansion tank in place, its an old 100# propane tank that I modified, cut up etc. Please note : I dont know that I would use a propane tank again, not because if the initial hazards but because of the smell, thats right, they stink to high holy heck. I first took off the valve on top to let the tank air for a few days, then I drained the oil (just let it come out on my garage floor and used some oil sorbent to pick it up) it wasnt much oil but omg even after i got rid of the oil sorbent, it still stunk up my whole garage, worse part was some of the oil got on my work clothes and the smell just made me sick. Anyways, then I filled the tank with water and let it sit for a day to get into the pores etc. Then emptied it, stood away from it and tested that all fumes were gone with a cutting torch, it was good to go.

now when its time to fill the boiler with wood, we can just say "go feed spongebob" hahaha :smile2:View attachment 211633

Spongebob, that's great!

 

[tooold]

If it starts slow, try blocking the top part of the open door with cardboard. Leave about one inch gap on the bottom for the air to come in. If the cardboard starts burning, just shove it in the firebox. If it works good for you, make a reusable one out of metal.

 

[feader72]

If it starts slow, try blocking the top part of the open door with cardboard. Leave about one inch gap on the bottom for the air to come in. If the cardboard starts burning, just shove it in the firebox. If it works good for you, make a reusable one out of metal.

so the purpose of the cardboard would be just to aid it in starting with extra draft?? Sir did you see on the first page of my posting where i posted pictures, there is a post called "more pics" and there is a photo "114_4791" it shows the door and in the center of the door is a pipe end cap with a rod for turning it. This pipe cap was installed just incase I needed more draft than what is supplied by the tubes. That pipe cap has multiple holes under it with a grd8 bolt n nut welded so that it can unscrew and allow more air into the fire for starting purposes. That would be pretty similar to the piece of cardboard correct? Thanks again for all your input i apprecaite it

 

[CJ1]

I dont have a picture of the return to the boiler, but Ill try to explain as best i can, when you are looking at the front of the boiler (door) on both right and left sides near the bottom are where the return comes in (both sides) and I made a balance tube that goes from 1 input to 2 outputs (return is one line but split it / balanced tube to 2 ends on both right and left so that the return flows equally on both left and right sides, it also has internal baffle to divert the return water omni directional?? wording might be funky there). I dont fully understand your post tho', might just be me, but the water exits out the top of the boiler in the center of it just back near the exhaust and from there it goes to the storage tank (an 80 gallon hot water heater that was repurposed and re insulated, I changed both the in and out on the tank from 3/4" ip to 1" ip) from the storage tank it heads out to the house and when it gets to the house it goes to the y strainer then to the heat exchanger. After it exits back from the heat exchanger, goes back to circulator pump and then the return to the boiler via the balance tubes. You do not think this is adequate? can you please clarify for me?

The only place you have to worry is in the boiler itself, you don't want any dead spots or places of no flow. Especially with a small volume of water. You will definatly want to leave your pump running. the problem with a small volume of water is if the boiler is at full burn and you loose power, the pump stoppes and the water will boil very quick. That is not good. Even if the air door/blower automatically shuts. There is alot of stored heat in metal. All of mine were open vent and auto shutdown. I had 1 person mess with the airdoor on his unit and it hung open. Unit ended up going to steam and blew one of the side seams out of the water jacket. Thes units have a 1-1/4" open vent and it was not enough to keep from building pressure. They hold over 400 gallons of water also. CJ

 

[tooold]

Just so the air gets to where it needs it. You could always direct it toward the bottom of your fire. By the way....good job on your project.

 

[feader72]

The only place you have to worry is in the boiler itself, you don't want any dead spots or places of no flow. Especially with a small volume of water. You will definatly want to leave your pump running. the problem with a small volume of water is if the boiler is at full burn and you loose power, the pump stoppes and the water will boil very quick. That is not good. Even if the air door/blower automatically shuts. There is alot of stored heat in metal. All of mine were open vent and auto shutdown. I had 1 person mess with the airdoor on his unit and it hung open. Unit ended up going to steam and blew one of the side seams out of the water jacket. Thes units have a 1-1/4" open vent and it was not enough to keep from building pressure. They hold over 400 gallons of water also. CJ

ok so basically your saying that I should probably also research a battery backup (UPS) that would supply enough electricity for say 1 hour in emergency situation to power the circulator pump correct? that was one of the reasons i selected the non electric air intake regulator so i would only have to concentrate on backup power for the circulator. furthermore by your reply, it actually sounds as if i should plan on having the circulator run at high speed (3 speed circulator) so that the water is continuously moving around?

 

[shelbythedog]

Secondary tubes look quite similar to those in my Quadra-Fire, definitely have not had a problem with them plugging. Only difference is that above my tubes there is a cement board like layer, about 1/2" thick, which is insulated by a ceramic blanket. The thought behind that is to insulate the burn tubes and get them hotter. I think you are onto the same idea putting fire brick on the top of your firebox. The one issue that jumps out at me is ash removal. Are you going to have to remove the grates every time you want to scoop the ashes out? I burn right on my firebrick, no grates, then just reach in and scoop the ash out. I certainly wouldn't want pull hot grates out once a week to make room for an ash scoop. Regardless of any critiques we have for you, the project looks great, you definitely have a talent many wish for.