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I would settle for damming up Edinburgh ;). We are ok, if we ever flooded you would see Noah sail past the window :D. Our drive way washed away the other week . all the stones are at the bottom, oh well wheel barrow time.
 
A little mini boiler update.

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I have the chimney roughed into where I can heat it with the big propane torch and run hot water through the shed floor heating lines now.
So far I have been heating it up to 180 - 190 F twice a day with the big torch and that bene keeping the shed at a pretty comfortable 55 F. I probably would have had it running on used oil by now but this weeks big snowstorm and related issues took priority.

I'm just waiting for a second pump that goes under the house to show up so can finish the plumbing under there and start pumping hot water to the house.
 
It keeps me out of trouble and gives me reason to occasionally feel I am more a tiny bit more skilled than the typical internet surfing bum. :p
 
I got back to the project for a while over the last two days. I got the burner mounted and the oil feed lines plumbed in and even did a test run yesterday.

I'm reusing the oil burner system and oil/nozzle preheat systems from the old boiler. The test roun went okay for the most part. The nozzle was way too big for this boiler though. 1.75 GPH running at ~ 160 PSI so that had to be changed out. Lots of chuffing puffing and soot production on last night run even with the pump turned down to it bottom end limit of ~80 PSI nozzle pressure.

Today I took the preheater assy out and cleaned it up and switched it over to a 1.2 GPH nozzle. It ran much better but ws still just a bit high on the fuel delivery and was still making soot plus puffing bakc a bit so I went down to a 1 GPH nozzle.

After that change I ran it for ~5 hours straight at ~120 PSI nozzle pressure without problems heating both the house and the shed. :cool:

Here's what the oil/nozzle preheater unit looks like taken apart.

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And here it is assembled.

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I don't know why it went blurry and dark in the next shot of the bottom.
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Basically it's a piece of 1 .125" x 4" solid copper bar stock with a 3/8" threaded passage going from end to end in line with the brass nozzle holder that itself is braze welded to it. The 3/8" passage is threaded to increase its surface area plus there is a 3/8" steel rod that fits inside the bore to keep the oil flowing along the threads for maximum heat transfer. Without it the cold oil going in will tend to develop a laminar flow effect where it won't transfer the heat from the copper into the oil evenly.

That passage is drilled offset in the bar so that a cartridge heater can be installed parallel to it. Initially I had a 3/8" 500 watt cartridge heater in this when I made it but it burned out and I only had a 200 watt one to replace it so I added an external jacket type 350 watt heater to the outside to make up the difference. That's the grey jacket held in place with the two hose clamps.

Up at the front just under the nozzle holder is a thermocouple that reads the temperature for the PID controller unit that regulates the heating.

The way it works is used oil is too thick to spray in a fine mist like fuel oil or diesel fuel will on a normal oil burner furnace so it has to be heated up to get it thin enough to spray into a similar fine atomizing mist. To do that raw heavy oil needs to be preheated to 300 - 400F depending on its viscosity. I run mine set at a 350 F but as with today where it's - 15 F and below if the oil is not heated up enough in the supply lines before it gets to the heater assy the 550 watts of heaters top out at ~320 - 330 F and never cycle off. As thick as this load of oil is I would like to have it heating closer to 400F but with the temperatures we are having I would need to be running around 750 watts to reliably manage it.

Still at a the 320F preheat it's atomizing well enough to burn clean but the flame is noticeably sputtery from the oil spray not being atomized fine enough.

So there's the secret to how you convert a old fuel oil furnace burner unit to run old used oil as fuel. ;)
 
Very impressive.
Does the igniter have to be run continuously, or is the flame self-sustaining?
Presumably you have a flame sensor ?
 
It runs the same as any fuel oil furnace where the ignitor is on as long as the motor is on.

No I never had a flame sensor on it before but I may add one, being I just found photo cell one on a junk box the other day, for this boiler being the control system is simpler and I should have at least one or more spare analog inputs on the PLR controler that I can setup to work with one this time.

I use the Teco PLR units from here for anything that needs any degree of sophisticated logic control.

https://www.bb-elec.com/Products/Co...rs/TECO-SG2-V3-Programmable-Logic-Relays.aspx

The SG2-20HR-D are my preferred choice for boiler controllers. I have several that have been in seasonal to near continuous operation for about 10 years now and have never had any problems yet.

https://www.bb-elec.com/Products/Datasheets/SG2V3_Programmable_Relay_Specs_1016ds.pdf

If I didn't already have a few spare SG2-HR-D units laying around I probably would have went with one of the SG2-20VT-D Modbus units and set it up to be home network accessible so I could see what it was doing at any time from any of my home computers.
 
More detailed test and tuning runs today.

The 1 GPH nozzle seems to be a good fit for the system and recovery time with the house and the shed on together is about 1/2 a degree per minute which gives me a burner reserve capacity of roughly 25 - 30,000 BTU's above my maximum heat load. :cool:

I do have an occasional minor smoke blow back on startup so I may have to add a cold air supply that operates independently of the blower and that should also help with dampening a intermittent flame flutter I get when a bit of wet oil runs through the burner. The old boiler had a vent slot cut in the bottom of the door to prevent that effect and having the firebox front plate the burner mounts into propped open about 1/8" at the bottom with a small screw stuck in it seems to cure the fluttering effect so a dedicated cold air supply should fix it plus if it does blow back it would vent the smoke outside.

The steel oil supply line seems to be working quite effectively as a oil preheat of sorts to get it up closer to room temp before it hits the filters and it is up to room temp by the time it does get to the pump. The filter suction gauge showed ~2 PSI suction yesterday at -15 temps so that well within the 5 PSI green range. Today at 10F its reading ~ 1 PSI.

RIght now I have it running with a PID controller as the main boiler heat control and the pumps plus house furnace fan are on manual and it's a nice 70 degrees and climbing! :joyful:

I do see that i don't have enough water circulating to the house furnace heat exchanger though. The pump I put on the house circuit was a mystery Taco pump I had no way to identify so I figured it was a larger one given its size but the flow rate is way lower than what I need. The house circuit holds ~ 2 gallons of water and it takes it ~35 seconds to get hot water returning after the system cold down which says I have at best 4 GPM flowing whereas the old boiler was pushing ~8 GPM on ~700 feet of line using two high head capacity Grundfos UP26-99 units with ~32 feet of head capacity each. One pushing to the house and one pushing the return line back.

I have the boiler set at 190 F but I am only getting about 120 F air duct temps right off the furnace where with the old boiler that would have gotten me 150+ which is about 90 - 100,000 BTU's heating capacity. My guess now is the mystery Taco pump is a older model 007 series which is a ~ 10 foot head capable unit. I do have a spare Grundfos UP26-64 pump laying around which would be a bit overkill (25+ foot head capacity) but it would give me more than enough flow.

At least now I know what my mystery pump is. :p
 
Not a darn thing. :p

I did outrightly buy my friends old 1500 watt Paris Dunn rig the last time I visited a few months ago. Paid them cash plus dropped enough extra on them that they have no excuse to not have on the ground next time I visit later this fall. :D
(still sort of doubt they will have it down by then though. ) :rolleyes:

Beyond that the mini boiler got used all winter. I had a few minor problems I had to rework . The 3/4" line set going to the house got pulled and replaced with a single continuous set of 1" line so now it circulate more than enough water using the single Taco #9 pump. :cool:

Also the the Teco PLR unit and complete smart control system got put in which works very well! The 550 gallon bulk tank that was sitting in front of the shed got moved to the side of the shed where it belongs about two weeks ago as well. The overall oil usage for last winter worked out to look like it's going to be using about a ~ 1000 gallons a year which is about half what the old boiler used, so the overall efficiency is far better which I largely attribute to the mini unit having far less surface area plus being in a well insulated building thus having substantially reduced idle time radiant thermal loss issues.

Since then I have also acquired about 2000 more gallons of used oil plus rebuilt a 3000 gallon bulk storage tank to hold it which at the moment puts my overall collected oil at ~4500 gallons. Rather thinking I will need to get a second 3000 gallon tank in the next year or sooner now.

As for the wind generator I did start stringing the power lines from it to the house entryway shed the other week. I am residing the house so once the new siding is done I will be pulling those into the house entryway where I will have the Grid Tie Inverter system for it.

Mini boiler with completed oil lines and filter plus control systems.
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That's all I have for updates I have for now for this threads related topics. ;)
 
It keeps me out of trouble and gives me reason to occasionally feel I am more a tiny bit more skilled than the typical internet surfing bum. :p
Not with a camera your not :p lol
 
Love the duct tape :). Obviously a vital part of the spec!
 
The Parris-Dunn system must be 70 years old or more, no? What sort of shape is it in? Interesting design, I would love to see pics when you get it installed. What are planning to use for the inverter?
 
The grid tie inverter will be one of my own older designs repurposed to work with whatever generator I end up with. They're pretty easy to build once you know the basics of them.

The Parris Dunn unit was used on their farm from the 30's until the they got rural utility power sometime in the early 50's.
 
More assorted updates.

The Parris Dunn 1500 watt wind generator made its way home last month after sugar beet harvest! The blades are junk and the unit got a bit roughed up on the take down (they torched the wooden blades off, WTF? :mad:) and I got screwed on the bill for taking it down at that. But it's home and mine now!

It needs a major rebuild as well. Bearings are shot and from what I can see the windings are likely pretty bad off as well. I might get lucky on that part but I have doubts until I get it in the shed for the major go through job. :(

I got about half the shed floor epoxied this spring and then the whole project got abandoned for the summer. This week I finally got back to it and cleaned it out so that I can work on bigger projects and stuff this winter. The permanent workbench got built plus the bench top got sanded and covered with the Bar Top epoxy sealer today. Once that's cured fully in a few days I can start doing other things like clearing out the other half of the shed so I can finish the floor epoxy over there and put in the permanent shelving and other stuff that goes on that side.

The boiler been on for ~ two months now and burned ~300 gallons of oil. I also put a double layer of Reflectix insulation on it to cut down on heat loss into the shed. Last winter it would run about 70 - 80F in there just from heat loss off the boiler alone. Now it stays at the ~55 - 60 F the shed thermostat is set at.

Used oil collection netted me another 2000+ gallons so far which puts my on hand stock at near 7000 gallons now or at least ~6 years heating supply if I never collected a drop more. :cool:
The 3000 gallon tank got redone and set so everything that was in totes got transferred just before the last 2000 gallons showed up. It's full and now I need to get a second 3000 gallon tank ready by next year.

This spring a work trip netted me a 1930's - 1940's Burke horizontal mill which I fixed up and plan to have as a permanent fixture of the old shed. I even went so far as to build the stand for it from a old 3/4" sheet of plywood that been outside for a year or two which given the weathering made it a perfect aged match for the old mill. best guess on age and limited identification numbering (no serial number, just machine number) makes it a WWII military production unit.

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Also that trip got me a huge mid 90's Baykal table sheer rig. It came from a fabrication shop that had a bad fire. The sheer is so massive (~3.5 tons) that it didn't get any real damage beyond the plastic components near the top being melted. The rest of the damage is just superficial heat damage to the paint and some minor rusting from sitting outside for the last two years. All major critical mechanical and structural components are fine.;)

Shearing capacity is ~ 100' x 3/16" or 72" x 1/4" steel plate. :cool:

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