I'm building a homemade boiler

[warno]

I was worrying about putting this on the forum because I know how most feel about somebody building one of these units. But I feel I'm doing a pretty good job so here's my build thread on my boiler. I'm building this at my work place. I started in February this year. Let me know what you guys think. Any comments or concerns by all means let me know.

With what I know now I would have built a gasser but I was fully committed to this design before I came to that conclusion.

My plan was to be into the boiler for less then $1000 and then the cost of the install added to that. I'm doing all the work myself. All welding is either MIG or TIG welding. All joints are double welded where possible.

Here's some progress pics of my build so far

It started life as a 126 gallon upright propane tank. I cut the top out and started with my ash pan.



Then I added some legs and a feed door frame.



Added a heat exchanger adaptor to the tank and a water cooled baffle.





Built a cardboard heat exchanger template.



Then built a heat exchanger



mounted it and started the water jacket floor. My fire box bottom will be lined with fire brick.



Added a front and rear plate to the water jacket



Flue adaptor, water ports and forced air intake pipe.



Sides to the water jacket



A front view



My fan assembly I made up

 

[velvetfoot]

I am always amazed at the skills, never mind the facilities, that people have at their command. Incredible.

 

[Fitter 73]

Nice job so far!
Hopefully you will get some more constructive feed back.
Although I am fairly new to the site and the "gasser" venue.
I am a third generation pipe-fitter by trade, and current owner of a commercial HVAC buisness that has been in my family since the sixty's.
I will say that I have seen some mass produced equipment from different manufacturers hit the market place over the years, that had far less time, planning, and attention to detail put into them.
Keep up the good work, and update us with your future progress.

 

[Jags]

Nice fabrication skills. Your build looks to be a well thought out plan. Very interested in the final performance.

 

[Bret Chase]

That looks good, and definitely not a hack job.... are you planning on getting it ASME certified, or inspected by the state?
or is it not actually a steam producing boiler, and just heats water to 180 or so?

 

[warno]

Thanks for all the positive comments everyone.

I plan on running my aquastat at 180 for the high side. So I shouldn't be building any steam unless I have an over fire situation. It's actually going to be an open system with a over flow similar to a Garn so in the event of a boil over it will dump on the ground.

I'm in the process of getting my doors, all 4 of them, ready to hang. I still need to build hinges for them as well. The top panel is cut and I have my access opening flange and panel cut as well, I just need to get them added on.

 

[duramaxman05]

Good job. Looking forward to seeing more progress being made. I have always want to build one but just havent done it. I would like to build my parents one. Maybe one of these days. Keep up the good work.

 

[OH_Varmntr]

I was worrying about putting this on the forum because I know how most feel about somebody building one of these units. But I feel I'm doing a pretty good job so here's my build thread on my boiler.

It is quite evident you know what you are doing.

What is the capacity of the water jacket?

 

[Bret Chase]

Please don't forget to put in a couple zinc anodes....

 

[mike van]

Lotta rod in there - Nice work -

 

[warno]

It is quite evident you know what you are doing.

What is the capacity of the water jacket?

It's about 120 gallons give or take a few.

Please don't forget to put in a couple zinc anodes....

Is it zinc anode rods? Where can I get those? I found some aluminum ones at the hardware store but that seemed strange. I have only ever heard of magnesium anodes before.

 

[Bret Chase]

It's about 120 gallons give or take a few.



Is it zinc anode rods? Where can I get those? I found some aluminum ones at the hardware store but that seemed strange. I have only ever heard of magnesium anodes before.

Hmm.... in illinois..... Around here, I'd say go to any boatyard. there, not sure.. basically you need a zinc *something* in the water jacket... the zinc gives up it's electrons easier than iron does, so it makes your boiler last far, far longer... You might want to look at a place that sells OWB's.... my cousin has one... and it has zinc anode blocks...

 

[leon]

I would find out if your homeowners insurance will even cover a
non ASME rated "boiler" let alone a homemade one.

And if not make it an unpressurised water stove out of it and put it in outside under a lean to use it.
Any chilled compressed gas is a completely different animal compared to hot water approaching steam temps.

 

[warno]

I would find out if your homeowners insurance will even cover a
non ASME rated "boiler" let alone a homemade one.

And if not make it an unpressurised water stove out of it and put it in outside under a lean to use it.
Any chilled compressed gas is a completely different animal compared to hot water approaching steam temps.

I called my insurance company before cutting the first piece of steel. They are ok with it. And this unit I'm building will be completely open to atmosphere at all times so it won't be able to build any pressure.

Where I work I hold ASME certifications and even with that I didn't want to potential for a "bomb" to be in my back yard.

Thanks again everyone for all the positive feedback.

 

[PassionForFire&Water]

Very intrigued by the combustion concept.
Make sure you burn very well seasoned firewood and have anti-condense protection on your boiler

 

[maple1]

Interesting build for sure - keep us posted.

I can already plainly see you are way ahead of my old boiler re. heat transfer area, and the water cooled baffle spot is also interesting.

Is using some radiant heat off of it part of the plan also? Looks like there might be a fair bit from the exposed bottom part of the firebox, even with some firebrick there.

(Almost looks like a pellet hopper in the background of the second & second last pics, likely isn't though?)

 

[warno]

Very intrigued by the combustion concept.
Make sure you burn very well seasoned firewood and have anti-condense protection on your boiler

Almost all my wood this winter will be oak lumber, from our sheet metal skids at work, mixed with wood from my dad's pile that's been seasoning for over a year now. I'm running a thermomix valve on my return line for my return protection.

Interesting build for sure - keep us posted.

I can already plainly see you are way ahead of my old boiler re. heat transfer area, and the water cooled baffle spot is also interesting.

Is using some radiant heat off of it part of the plan also? Looks like there might be a fair bit from the exposed bottom part of the firebox, even with some firebrick there.

(Almost looks like a pellet hopper in the background of the second & second last pics, likely isn't though?)

I wish I could use the radiant heat from the exposed steel but the insurance company said I have to put it outside my current buildings or they won't have it. So I'm building a small shed around it. It will be cozy wrapped in its insulation blanket and in its own little house.

The thing in question in the background of the pics is our cabinet sand blaster at work.

 

[duramaxman05]

What does running a mixing valve on your return do? I am still learning

 

[warno]

It prevents the return water temperature from going below 140. If your return temps are too low you could shock the steel in the boiler and cause premature problems. Also low return temps around condensing temps could cause condensation in the heat exchanger and flue pipe causing. (Or at least that's what I've read)


I do have a question on wiring for anyone who can help. I'm installing a float switch in the water tank that I would like to shut down the pump and fan assembly if the water gets too low. This is the switch I bought (broken link removed) could anyone tell me if it's possible or how to wire the switch to shut down my pump and fan?

 

[OH_Varmntr]

Warno, I hope to help you with your float wiring question. I'm an electrician at a steel mill, for what it may be worth. I will explain this in the simplest of terms because I do not know your level of electrical knowledge.

First off, what are you going to use to control when your fan turns on? An Aquastat? When do you plan on running your circulator? 24/7 or on demand?

The control power that is used to start your pump and fan relays should be ran through the contact in the float switch. You will need to set the float switch up so that when the float is down, or indicating a low water level, the contact opens the circuit and shuts down the pump and fan.

So in basic theory, if you are telling your fan and circulating pump to run, the signal should first pass through the float switch before continuing on to the relays which start your fan and pump.

If you provide the information on the control system you'll be using I can further assist you.

 

[HisTreeNut]

Nice...on the build (and advice also )

 

[warno]

Warno, I hope to help you with your float wiring question. I'm an electrician at a steel mill, for what it may be worth. I will explain this in the simplest of terms because I do not know your level of electrical knowledge.

First off, what are you going to use to control when your fan turns on? An Aquastat? When do you plan on running your circulator? 24/7 or on demand?

The control power that is used to start your pump and fan relays should be ran through the contact in the float switch. You will need to set the float switch up so that when the float is down, or indicating a low water level, the contact opens the circuit and shuts down the pump and fan.

So in basic theory, if you are telling your fan and circulating pump to run, the signal should first pass through the float switch before continuing on to the relays which start your fan and pump.

If you provide the information on the control system you'll be using I can further assist you.

I sent you a message. Thanks

 

[leon]

It prevents the return water temperature from going below 140. If your return temps are too low you could shock the steel in the boiler and cause premature problems. Also low return temps around condensing temps could cause condensation in the heat exchanger and flue pipe causing. (Or at least that's what I've read)


I do have a question on wiring for anyone who can help. I'm installing a float switch in the water tank that I would like to shut down the pump and fan assembly if the water gets too low. This is the switch I bought (broken link removed) could anyone tell me if it's possible or how to wire the switch to shut down my pump and fan?

If it is not a triple aquastat you should return it and buy a triple aquastat as that is what you need

Is this unit a submerged thermocouple for a honeywell or bell and gosset triple aquastat???

Your going to have to decide how much water you want left in that beast B4 you shut it off
Are you buying a replacement water stove fill plug to control the evaporation rate??

Submerged thermocouples are either installed on the top of the boiler when it is used for hydronic heat
or near the base of the steam chest which is where the water level covers the thermocouple and senses
a boil out and shuts the boiler off.

Are you installing a bypass loop in the home to trick the boiler into thinking that its always warm and to save fuel??

 

[velvetfoot]

I have one of these in my system. They seem pretty commonplace. http://www.homedepot.com/p/Safgard-Low-Water-Cut-Off-120-Volt-Oil-Hot-Water-45-550/203205175 . It uses the conductivity of the water, or lack of it, rather than temperature or a float to trip the boiler. It's specifically made for this purpose.

 

[warno]

I have one of these in my system. They seem pretty commonplace. http://www.homedepot.com/p/Safgard-Low-Water-Cut-Off-120-Volt-Oil-Hot-Water-45-550/203205175 . It uses the conductivity of the water, or lack of it, rather than temperature or a float to trip the boiler. It's specifically made for this purpose.

I have seen those before. Thanks for the heads up on it. I already have my float switch in hand though. I got some wiring help on how to make everything work together with what I have.