Garn is up and running

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$90/cord for mixed maple/yellow birch over here. Lakeland Times in Minocqua had an add for $120/cord on oak, don't know if they are selling any.
 
Ya, at 67.5 a cord it's not even worth my time to "scrounge" for wood. It's nice to have the truck come in and put it right where you want and in a nice pile.
 
I agree with Rick and George...after a couple of years of burning the Garn, one looks at the temp and knows to:

1. Build a fire or not.....depending on temp outside and knowing if you will need the heat or not. instanteous.
2. Whether the HX is in need of cleaning. Has it been a few months minimum and getting up in the high 500's on every burn? Well, it would likely benefit from some scrubbing. But, I have only done it once a year and I know I lose some efficiency.


Other than that, there really are no other decisions. OK, time to clean out the ashes? When you open the door, you know the answer to this instanteously as well.

For me....the only thing I don't know instanteously is my water level, as I never yet installed a site glass to allow me to check this. But I also have learned that IF the manhole seal is nice and fresh, when I put the lid on right (about a fingertip gap evenly all around), and a little brick on top of it....then I won't lose water at all unless I overboil....and then that really only happens once. SO again, this is a known really as well (and would be exactly with a site glass) and every 6 months when you take the water sample....you KNOW the answer to your water level....or just put more in when she is open.

The only other thing to "learn to know", for me, is the manhole gasket. Just seems like it can't take too many manhole cycles before needing to be replaced. Maybe 3 or 4. Then I find it breaks/loosens in just on area, which is enough for steam to vent....and then you get a little wet insulation....and your water level becomes more unknown. OK, so replace it every 18-24 months. Just need to find the right stuff to stop giving Dectra $20 for a strip....though really that isn't too bad.

Oh yeah, and for me, the anodes. Everytime I open the beast every 6 months, it is a new rod. WIsh I knew why....and Mike keeps saying it isn't water.....has to be electrolysis. I should look into this more....but it is grounded to the motor grounds....
 
I had problems with my manhole cover leaking till I installed a 3/4" backer rod ring on the manhole. I now get no leakage. The backer rod takes out the minute voids between the seal and the manhole riser. I found if I was not getting any vapor out of the overflow tube when the temperature was 170-180 degrees that my manhole cover was leaking.
 
Oh yeah, and for me, the anodes. Everytime I open the beast every 6 months, it is a new rod. WIsh I knew why....and Mike keeps saying it isn't water.....has to be electrolysis. I should look into this more....but it is grounded to the motor grounds....

I was chatting with my electrician friend about this style boiler and running the electricity to a new panel. He thought that grounding this unit properly and grounding the service with the shallow depth to SHW may create a challenge. Wonder if this is attributing to your premature anode wear?
 
We always bond the Garn tank itself right to the main service ground in some way or another.
Just looked at a 2000 that has been in service for 5 years and the anodes are just now beginning to look like they should be replaced at the end of this season.
Grounding and stray voltage, especially in older home can be a significant issue at times and something to be aware of on any boiler system.
 
Heaterman: is the insulation board intended to separate the boiler/tank from the corrosion present on the concrete slab? Or was the thought to just insulate the bottom?
 
Heaterman: is the insulation board intended to separate the boiler/tank from the corrosion present on the concrete slab? Or was the thought to just insulate the bottom?


Just to insulate the bottom of the Garn. A 4' wide sheet is the exact width of the skids under the Garn which are about 10" wide and run the length front to back. We've found that a 2" thick piece of standard density EPS will compress about 1/4" over time.
 
We always bond the Garn tank itself right to the main service ground in some way or another.
Just looked at a 2000 that has been in service for 5 years and the anodes are just now beginning to look like they should be replaced at the end of this season.
Grounding and stray voltage, especially in older home can be a significant issue at times and something to be aware of on any boiler system.

My experience is similar. I have been running almost 3 1/2 years and the anodes are showing some scale but are at least 2/3rds left. I am bonded to my main service panel which is grounded to three ground rods below and outside the footings of the basement and a 90' section of 1 1/2" copper that runs from the basement to the old well pit that is 14' below ground level. I did not run a separate ground for the Garn as I figured my best potential is at the main service panel.
 
Here's what I have tried with the grounding. I removed the paint from the lifting flange of the garn (on the back end) and I think drilled a hole there....or was the hole there? No matter. I ran an 8 AWG copper wire, bolted through that hole and connecting to the garn steel (no paint), over to the ground coming into the Garn building. This ground is the copper wire in the 12AWG wire coming out to the building. This line is fairly long (likely 100' or so) and goes to the main panel in the house. At one time I also had the 8 AWG wire running to a ground rod I installed just outside the garn barn along the roof eave....where it should be fairly moist.


My main panel has a couple of ground rods driven into the ground. I have about a foot of dirt here and then all shale....so I drove the rods as much as I could...not easy...and they are on a 45 angle as opposed to being straight down and deep. Ground is generally wetish were the rods are as they are along the roof eave.

Whereever I have a pump installed, it's ground is tied to the ground lug on the pump housing. I've assumed this is going to provide a ground for all the sections of copper piping I have that are "separated" from others via PEX. My thinking is that all the copper in various "regions" (I have the Garn barn region, the outside oil boiler shed region, and the house piping region. Each region is "insulated" via buried pex running between them...save water conduction). Each of these sections is tied through their pump ground wire. Each section is roughly 40' apart from the other, with the oil shed in the middle.

Is there more that I can do? Should I run a larger dedicated wire between all the sections? I have always wondered if my earth connection is good enough....would improving this help? I'd think it would be about keeping all the sections at the same potential. Perhaps relying on the 100' 12AWG connection back to the main panel is the problem? And then another 50' length to the oil shed (with the oil boiler)? Everything is in conduit, so I can, in theory, fish through a heavy wire. Pull ropes are all still in place.
 
Electrolysis - results from a "noble" metal (i.e. copper, bronze, brass, etc.) in close proximity to steel (a sacrificial material). It can also result from improperly grounded equipment and/or an improperly grounded electrical service to a building. No water treatment can prevent this form of corrosion. Connect only non-galvanized steel pipe to GARN® WHS and ETS units, and install dielectric couplings where copper pipe connects to steel pipe. Sacrificial anode rods provided with your GARN® reduce the potential for this type of corrosion. If, during periodic inspection, the anode rods have decayed significantly, it is most likely a result of electrolysis.


This is from the Garn manual. I would advise to have an electrician and your Garn Rep over and go over your install. It will be a small cost to preserve your investment. It sounds to me like your main panel may not be grounded correctly and it floats around until it finds a good ground IMHO

you could post pictures of your install. there are many here with great knowledge.
 
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Bruce, is your neutral bonded to ground or enclosure at any point beyond your meter base or main service disconnect? Did you run three wire or 4 wire from your service disconnect to your service panel in the house. I am visualizing your power going from the house to the Garn building?
 
Dielectric unions are about the worst things ever invented for the plumbing industry. They cause or fail 100% of the time. I have never removed a Dielectric union that wasn't closed up and fully corroded inside. Whether it on a boiler,water heater or anywhere in the piping system.
However I will say, I have NEVER. Seen an electrolysis failure in the 23 years in the trade. Please don't take this the wrong way, as I am not suggesting someone circumvent the almighty "CODE". But I have seen 200 year old farm houses with not a stitch of grounding to pipes with perfectly fine and wide open galvanized pipes. Yup, not closed up at all. I have seen hundreds of water heaters and boilers with brass or copper directly tied to steel or cast iron without a smidgen of build up, corrosion or early anode failure. If fact these are the best looking and oldest heaters I come across. City water or well water, treated and untreated.
I in my professional opinion, know that bonding alone accounts for the majority or all of the corrosion found in,at,or around a dielectric union. In 1 year a 3/4 DU will close to a quarter inch or less with bonding, by removing ALL bonding from the piping, or in cases where everything is pex, the corrosion is near non-existent. This is for South half of Michigan.
Electrolysis only needs millivolts to start doing its thing. And I find it suicide to use dielectrics on a Knight ,Viessman,or HTP, but some do, about as smart as bonding pex too.
 
George: I have triplex running from the meter into the house panel (3 wire). In the panel, neutral is bonded to GND via the "green screw" in the panel. At no other place does the neutral tie to GND. I have a subpanel with 4 wires from the house panel out into the garage/addition (attached) but all power for the Garn/heating system originates from the house panel.

What if the ground and neutral were bonded out at the meter and in the house panel? While I understand this would then require 4 wire going into the house panel (treated as a subpanel).....what is the suspicion if everything heating system originated from the house panel? For this level of electrolysis to be occuring, I assume there has to be a potential difference between the plumbing somewhere, introducing the few mv to help force it along. Hence my thinking that if everything is tied back to the same point, it shouldn't be a problem. BUT, 100' long 12AWG copper will perhaps allow for some mv level differences? But far as I know and can tell, no current should be flowing through any ground.....

Out the back of the garn, I have black iron for ~8' and then a brass ball valve and then I switch to copper. This is on the supply and return. We had a considerable discussion years ago here whether it was OK to go from black iron to brass to copper and it was deemed OK (and it was also deemed OK by the Garn dealer). No copper straight to the Garn....no copper straight to the black iron. Brass in between. But there are no di-electric coupling adapters.

Given the rate of anode rod consumption, I am assuming there must be a problem holding everything at the same potential.....Given fairly long distances, pex isolation between segments of plumbing, I can only imagine that these potential differences are at work.

EDIT: I just measured the potential between the plumbing/GARN and the ground coming out the Garn barn and measure 0V, down to the mV level if you believe this little meter. It also measured 0V in the oil shed and in the house. So, this tells me the plumbing in each of the three buildings is all tied to the ground wire that is present there. Measuring between the different locations is a little tricky and will require so long wires/leads.

What else can I do to hunt down this problem? If there is no potential difference between regions, this would indicate something else....but with an anode rod every 6 months, it seems unlikely. Milke at Precision has repeatedly said it isn't the water inherently as the chemistry looks great. I'm puzzled.
 
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Vizsla I could not agree more on the DE unions. They are a guaranteed failure waiting to happen.
 
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