I'm building a homemade boiler

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How do I prevent this from happening in the of shut down months through summer? Will getting everything insulated properly help out?

I don't think you'd get the conditions that would create condensation in the summer. It would likely only be at this time of the year (or early spring), at which time you'd maybe be burning? But having water in there too will likely help and insulating - it likely came from the steel cooling off overnight then condensing moisture as the air heated up faster than the steel did when daylight comes. Were the pics in post 89 with the sun low taken in the evening? If the shed gets blasted by hot sun first thing in the morning that might cause temps inside to raise fast & make condensation. Leaving the door open for good air circulation while your finishing up the insulation & the rest of the job might also help.
 
OK thanks guys.

So, more progress pics now.

I started the trim work on the shed today and did a little more plumbing. I'm learning that a 300 ft roll of pex has a mind if it's own.

Here's what is hanging from the ceiling as of now. Lol

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Both heat exchangers are plumbed up.

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I used the snap on 90 bends to bring the pex through the ceiling. What a treat they were to use. I found that using a big zip tie on the first side snapped in to hold it there while you fight, for dear life, with the other side helps.

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And on the attic side of the ceiling. The coils run in series. This is the second coil in the system.

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This is the first coil in line.

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And where the lines go back through.

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This is the blower fan for the forced air system.

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And I took a quick pic of the shed before the rain really cut loose. I still need a few more sealer screws on the trim but the rain shut me down.

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A blow dryer helps to loosen up the coiled pex. You can also slide the pex through 1 1/4" pvc conduit elbows to make hard 90s without using fittings.
 
I finished the chimney flashing and pulled the boiler back out of the shed for foaming. I have a few things to do to the shed before it's spray foamed but that will get done this week.

I started the flashing at work and finished welding it at home. I didn't get a pic of it mounted up but here's what it looked like tacked.

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I've got a bunch done since the last update.

Chimney flashing mounted
Shed siding completed
Shed is insulated
Boiler is in its final place
Plumbing in garage is done
Electrical in garage is done



Couple pics of progress. sorry no pics of shed yet.

I had this guy supervising the whole thing this morning.

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I had to build the wall out for the plumbing to mount to it. It sort of worked out because now I can use the dead space behind the mounting board as garage junk storage.

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Circulator Pump mounting location

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Pump mounted

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I made up some aluminum mounts to hold the pump

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Thermomix valve plumbed up and mounted

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overall plumbing. It could have been alittle nicer but it will work for me.

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I know, I'm trying to finish things up.

I finished the wiring this morning early before work.

Things that are left to do:

Hook up overflow to shed wall
Duct work in garage
Insulation around boiler
Chimney weather cap
Refractory
Fill for pretreatment
Drain pretreatment
Fill for final time
 
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Couple of updated pics here

Forms for the refractory in the firebox

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Here's my aquastat override switch and indicator lights. The override switch is to shut the fan off when loading wood. You can also see some of the foam job on the inside of the shed

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Here's the ceiling. The foam job didn't turn out nearly as nice as I hoped. Alot of differences in thickness a couple of missed spots, but I guess you get what you pay for.

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Rear shot of the boiler, plumbing and Electrical is all done.

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Main electrical box and aquastat. The switch on the front of the box works with the float switch. If water level is good everything works as it should if water level is low it will shut down the fan and pump. And the switch allows me to override the float switch if need be.

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Inside the box is a bowl of spaghetti. I have a bigger box at work I plan to bring home to replace this one, since I'm already planning for more things in the future. But this one will run this winter.

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Just a couple of closer spots

The fan assembly

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Ground wires

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Drain adaptor goes from 1" make to 1.5" make for my drain hose.

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http://www.woodlanddirect.com/Casta..._a_7c2640068&gclid=CO2l4qCZqsgCFQiNaQodhJkMoQ

I bought 2 of those and I also got some stainless steel needles off of eBay. This is the part that makes me most nervous because if it doesn't go well then the refractory will all crack and break down.

Basically my process so far is:

Heat firebox with little space heater
Pour refractory
Shake out air bubbles with eletric hammer
Let cure for a few days with space heater running in firebox

I have never worked with refractory before so I'm hoping I do it right.
 
I'm hoping the shed won't get that hot. I'll be putting a ridge vent in the shed also so it shouldn't get horrible in there.
 
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Hobbyheater had a post where he was re pouring a base for a Jetstream boiler. He had a process for burning small fires to cure a large amount of fresh refractory, on a thread maybe a year ago.

He said something about a soot ring if I recall correctly.

Maybe if you read that it would help, in addition to what you planned.

Looks like a good project.
 
I put in my refractory tonight. That was pretty much a let down. I only had 100 pounds which seemed like alot, but it definitely was not. I'm going to have to build some hold plates and fill the remaining space with sand since I don't have the money to buy more refractory. I just hope what's in there holds up. I'll get some pics when I pull the forms off.

So for anyone doing a poured refractory piece, do like the packaging says and plan ahead. You only have about 20 minutes of working time before this stuff starts setting.
 
A little more progress today. I pulled the forms from the refractory, insulation around the boiler, I finished the feed door.

The refractory came out quite disappointing. I didn't get it shaken down good enough at all. I guess when it breaks down I'll dig it all out and fill the void with sand like I have to do on the front of the firebox.

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Feed door ready to go on once the fire brick are in the box. I end up filling the open spaces the refractory didn't get into with sand, then I welded the cover plate on half way.

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And the insulation is wrapped around the boiler. I used R30 glass mineral wool for this wrap. The left over pieces I stuffed up on top of the boiler for alittle thicker coverage up top.

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Great job and documentation, but the what scares me is the near boiler pex in the last picture. This has been a failure point often also when a overheat turns to a over pressure situation, becoming a real mess at the worst time. Being that its below the boiler could help but maybe others could chime in.
 
Thanks for the compliment.

Are concerned that the pex will melt off of the fitting? Also my boiler is an open system with a vent line, so that should eliminate the possibility of over pressurizing.
 
Sorry, I think your covered also understanding that a non pressureized system should stay below 190degf for water quality reasons as well, carry on!
 
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After work today I finished up the front of my firebox. I plated in the front with stainless steel and filled the void with sand.

The firebox isn't bad to get into unless I'm wearing my welding hood, then it's a nightmare. Very tight fit. But the front is done. Now I need to put in my firebrick and fill it up for the first fire.

I pulled the TIG welder out of the garage and set it up outside. Less then ideal but it had to be done.

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Yesterday I plumbed my vent line through the shed wall and redirected my drain line out towards the front of the shed.

Tonight I added my ridge vent to the shed and put my fire bricks in the box. All that's left is the duct work in the garage and the feed door on the firebox. I have a part time HVAC installer coming by tomorrow to help me get my duct work in. I'll also be putting the feed door on the fire box tomorrow morning. I hope the hinges hold up, the feed door is probably 80 pounds now after loading it up.

Some pictures

The bricks in the firebox are a combination of ceramic and standard firebrick.

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Here's where the vent line comes through. I built a little cover over it.

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Here's a shot of the vent line inside the shed.


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And the drain line reroute

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Home made ridge vent it has 2" hole that goes down inside the shed.

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If this 2" hole isn't enough I have a pilot hole drilled from the inside to add another 2" hole for more vent capacity.

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