who is the boiler expert on here???

I need to modified a naturally aspirated IWB to have a fan on the front like OWB's do so I can control the air going in and water jacket temp better.

 

Don't know that we have a boiler expert here. Not me anyway. I have in in-door wood gasification boiler. But a boiler expert I am not. I had a couple HVAC guys who do a good number of boilers install mine for me.

 

I worked for my dad's boiler shop for a couple years, my dad still has his boiler wit about him.

We have an iwb in the basement of the cottage plumbed into an LP boiler all feeding fan coils and kickspace heaters.


What model do you have? I know our iwb has a fan at the intake. Also what kind of circulation pumps and gpm in the setup?

 

Currently I have two taco pumps one is the 009 and then I got a 0015 taco with a speed selection since this IWB originally had a 3 speed Grundfoss on it that didn't work. The system overall works but I have it necked down to 6" instead of the 8" (?) that comes out of it. I am going to correct that and put the right pipe on before winter.

30gal IWB - I made this boiler atmospheric instead of pressurized since it had 2 pin holes that dripped in the front. Those holes have since stopped dripping since it's not pressurized. I just ran a tube off the top pressure tube and ran a vent hose to the top of my roof line. The air delivery is a port hole with a plate over it that is supposed to open and close when the coil spring above it expands and contracts when it's hot or cold. It doesn't work... I have to babysit the dang thing for 3 hours to get it leveled off and warmed up until i can shut the damper 7/8 closed and just trickle air in to keep it going. I also filled it with antifreeze so that it wouldn't freeze when i'm not in the shop during winter for a couple weeks. I tried to slow the heat release down by putting the 0015 taco on it and using the three speed dials. However when i did that it tended to boil the water jacket and blow the atmospheric vent tube off and fill the shop with antifreeze steam. I fixed that by putting the 009 taco back on to circulate the water faster and take the heat out. I bought the 0015 pump new off ebay but it didnt seem like it was pumping water at all. I am hoping to install a "air fan" on the front for more precise air delivery that will run off a water jacket thermostat. This would in theory keep the fire down to a lower and more even heat and not boil my water jacket. Hopefully the air fan will also allow me longer burn times too. I don't know if that will allow me to switch back to the 0015 pump or not??? I just want to get this little boiler to the point where i can fire it up and count on it to heat the shop for 9-12 hrs.

250gal Dahl OWB - this older boiler has the same set up as above and would like to switch it over to air feed based on water jacket temp as well.

The long term plan is to use one boiler at the house and one at the shop. I have 450ft between the two so just using one boiler to feed both isn't an option since good insulated pex is $8-$10/ft.

So basically I need the name of the parts I need for the "air fan" set ups to control my air feed to the fire box

 

those are kinda big pumps for most applications. what didnt work about the grundfos?
i would replace the coil spring and try to get that working properly before investing much into retrofitting a blower on the front.
if the firebox is big enough you might try lining it with firebrick. this will allow you a smaller fire that is easier to control throughout the burn. the brick will give you a more even heat output and continue to release heat to the water jacket even after the fire has gone out.
sorry, i know none of this answer your direct question of how to rig up forced air. my experience is with negative pressure downdraft burning and storage.

 

nuts, I need to at least do the forced air set up on the 250gal boiler. I don't think those springs work too well for my small IWB application either. I want the proven method of forced a air fan. it will be easier if i can put the same system on both units so the parts will all be the same. The grundfoss was old enough I couldnt get the rebuild insert for it so I just stole the 009 off the bigger boiler. I know it's way more flow than I need but it also helps heat the shop way quicker! I will experiment with the 0015 pump to see if I can get that fixed.

I know there's more expense to the forced air fan but I think it will pay off with longer burn times in the long run. The main thing is I go to work or sleep for 10hrs before I can refill and it would be nice to come back to hot coal bed to start it up again... The other thought is that i would like a more consistent heat which i'm not getting now. It will get 85*F in the shop when I'm there and run through the wood too quick. I'd rather have a longer burn with more consistent shop temp. I am going to try and do more insulation in the shop too...

 

Post a picture up of the boiler that you want to put the fan on.

You may have to fab one up.

 

I have no problems fabing stuff. I have a metal bandsaw, 2 welders, and a oxy/ace torch... Not much will slow me down.

 

30gal IWB - red hose is vent to roof line

 

This is the basic idea, out the fan flat against the front door so it doesn't impede loading it. And attaching it with an 90* elbow that I will fashion from something.

 

Here is the dahl that I got for $150. No air pump either but some sort of electrical damper system on it. I filled it with water and it holds and doesnt drip at all. Planning to flush it out good and put a big sediment trap on it to catch any rust. Also trying to find someone that does closed cell spray foam so I can get it covered with 2-3" to insulate it.

 

Does the iwb have an ash pan that you can open? I ask because once in a while I open the ash pan on our iwb at the cabin to get a fire going. The intake fan is on a t stat and won't turn on until it gets some heat going.

 

Is there no draft control run by a thermostat now? If that is the case, I would think it would be better to use something like I linked below instead of trying to install a fan and pressurizing a chamber that was meant to run on draft. If you have never seen one, they go in the water jacket and have a thermostat that you set. The arm and chain connect down to a draft door. As the thermostat gets hotter it begins to lower the arm and close the air off. The whole thing is purely mechanical. I'm not sure that makes sense?

New Horizon Corp, Inc.. Danfoss Draft Regulator

 

I will add an extra air intake next to the fan for this reason. I kinda already thought about that and do want the t-stat to handle the air and heat once the shop is warm but getting the jacket up to temp takes more air...

 

Yes that makes sense and I'll go take a look now. It's all air control to me... Neither boiler has a working air damper control system on it.

 

On the gassifier in my user image the primary control is what I linked to. It only turns off the fan once it hits the maximum temperature but the stat is what tries to keep it at the desired temperature.

 

I still want to know the name of the air control fan and price both options. If not for the IWB, I will probably go that route on the Dahl 250gal

 

I would think your best bet would be to find a brand of boiler that uses something like you have in mind and price a spare. Mine won't help you much unless you want to take a trip to the Czech Republic and pick it up there.