home made outdoor waste oil boiler experiment

[TheEquineFencer]

I was looking for info on a track torch and found this thread. here's my .02 worth from someone that uses hot water to heat my shop throught radiant heat in the floor. #1 question, what are you going to use to get the hot water from the heater to the heated spce? Pex piping, it rated for 200* only. if you buld pressure you get more heat, this would be a bad idea. if you using pressurized hot water you'll open a big can of worms. I'd add a LOT more tubes, you'll need a lot of surface rea to heat the water in a reasonable time. If this is a not pressurized vessel, just run a vent line up above the water level. For cutting the holes, use a hole saw to fit the pipes, they make a neater cut. If you heated area is above the top of the heater you will not need a pump unless you heater exchanger is really large. natrual convection will turn the water over for you more than you think. I'd use a copper heating coil and not a radiator for the exchanger, they transfer heat 100% better than a car radiator if that's what you were planning on. I have a new uncapped air handler here at my shop I've not used yet. It has everything for cooling and heater for a chiller system. It's rating is 12 Tons. I was going to use the copper coil for additional heating and then run ground water through the Aluminum cooling coil in the summer for A/C when it get's hot but my ground soil has too much clay for a shallow well I was planning for. I was working on something similar before the tornado came through, so my plans have changed a bit now. If you're going to burn waste oil only while you monitor it, I'd look into a babbington ball burner. They are easy to build if you want a neat burner. Go to youtube and look up my SN and look at the info on the burner. There's a Yahoo chat group that works with them too. I have the pipe here to build something like you're doing. But I was going to lay a section of 9 inch pippe on the side, capp both ends with some 12ga, cut a 4 inch hole in each end, run 4 inch exhaust pip through the middle and put a babbington ball burner in the end. I was going to tap the pipe on top and bottom for water connections and let the convection move the water to parrallel to my Taylor water heater. I'm just throwing some ideas at you, so don't take offence. Floyd.

 

[gardrail]

TheEquineFencer : I appreciate everyone's comments and suggestions. Even the ones that say this isn't such a good idea.

Quite honestly this is quite an undertaking for me as I've never welded anything water tight - or pressure tight. This has been quite a learning experience and a fun experience. The reason I haven't posted on this thread for a while was due to a combination of work, and other projects that pushed this on to the back burner. I have to admit I was somewhat irritated in myself when I found out there was a boat load of pinhole leaks in my welds on the bottom of the unit.

Some background on the pinhole leaks.... After cutting down the excess pipe lip on the bottom, and grinding down the welds I discovered that there was a bunch of slag intermixed with the weld. That was from my first few attempts of playing around with manual arc on a 60 year old Dayton welder. I managed to get the surface ground down flush, and grind out a bevel a week or so ago, and finally welded the bottom up good and tight. I tested the welds by using my air compressor and hooking a regulator up set to 10psi. After spraying down the welds with soap, and spot welding the little bubbles that were left - the bottom is now completely leak free.

I'll need to inspect the two water outlets on the sides to make sure they don't have any leaks, then check the top (I think there's one or two up there). So far she's coming along just great

I have to agree with TheEquineFencer on the number of heat exchanger pipes... Based on what I've worked with on this one, some additional concerns I have deal with air flow and will enough air be able to be sucked in by the siphon burners in order to maintain a good burn of .3 gal per hour....

PEX tubing is also a concern now that I've read the most recent post. The burner unit & boiler will be down hill from my house - possibly 10 feet lower than the basement. With 10 feet of head - it looks like with a cold system I'll be siting at 5psi. Even with this being an open design; I'm wondering if 5 - 10 psi would be too much pressure for the pipes to deal with. My original ideal was to get some 1" PEX and run that from the boiler up to the house.


Anyways - thought I'd post an update and to thank everyone for the comments!

 

[Train]

Anytime there's a waste oil burner thread I'm glued to it. Not quite sure what the concern is on the Pex. I just installed 400 feet of it and the stuff I used was rated at 100 psi at 180 degrees Fahrenheit. Now mine was for fresh water coming to the house but I know there's Pex rated for hot water heating.

 

[Raspy]

PEX can handle the pressure and temp it's rated for, but I don't like to push the limits.

In your case the possible problem will be stagnation temps that then go to the PEX. Don't let the boiler get up to boiling or full of steam, and then have that high temp water get to the PEX. This can happen with a pump failure or it the thermostat is off and then comes on, etc. Also, since the boiler is below the house, the hot water will thermosyphon up the piping. This can bring very high temps to the PEX too. Run Copper or iron pipe for at least some of the distance and be careful of unexpected high temps. This is a problem with hot water solar systems too, that are not set up right.