Fellow Garn Owners - Help Please!

[cmittlesteadt]

Hi Guys,

After a long, arduous road of constructing the Garn building, yesterday I did the first fill, preclean chem. and firing of the Garn. I actually preheated the water with the HX piped to my existing gas boiler to 85 deg. to avoid condensing during the first burn. I added a smallish load of wood and fired it up. Flue temps never got above 300 according to the controller. The tank temp topped out at 130. I circulated the precleaner in the Garn and all attached pluming for 24 hours according to the instructions. Today, I let it cool to about 110 and drained the water expecting to do the flush and final fill. After draining, I was more than a little concerned by the amount of gunk, and debris - there was LOTS of it at the bottom of the tank. There were many gallons of opaque white/rust colored liquid and most of the welds inside the tank were rusted. The inside of the manhole has a fair amount of rust started as well. There is a lot of white residue that doesn't rinse off of the surfaces of the inside of the tank. Since I'm a total newbie and know very little about this, perhaps none of this is uncommon. So, let me ask a few questions please:

1. Is the newly-rusted surfaces something that I need to be concerned with? It's mostly weld joints, but there are patches of rust in many places on the inside of the tank and the heat exchange tubes. Prior to adding the precleaner chemical, the tank had no rust whatsoever.

2. Is the white residue something to be concerned about? It doesn't come off even if I rub it.

3. There are pieces of debris of some type that are sitting at the very bottom of the tank. I assume that it's steel shavings or something like that because I can't rinse it toward the drain at the front of the unit with a hose. The debris doesn't float, it just sinks to the bottom. Do I need to remove all of that? (if so I'll need to crawl inside the beast)

4. Will the final chem treatment stop the rust that the precleaner chem has caused?

I can upload pics if needed. Again, I hope I'm over-reacting and there is really nothing to worry about here, but I don't want to do the final fill only to have to drain it all and do it again later.

Thanks!
Chris

 

[bpirger]

Congratulations! You've come a long way!

Before I did the first fill and the precleaner, we climbed inside the beast and cleaned everything out. There was LOTS of flatish metal pieces laying on the bottom....lots....probably many cups worth. We clean those all out best we could with a brush and hose. I suspect you are seeing the same stuff. Not sure where it is from....I'd think if welds were ground down they would look like this...these were flatish pieces, maybe the size of a dime. Many of them. Fairly thin.

The white coating everywhere is normal. In fact, after your burn for awhile with the treatment, or at least in mine, I have a white coating....especially on all the HX tubing. It grew to be a little bit fuzzy even. I have a thread here from this past Novemeber where I had a good amount of this white precipate floating on the surface of my water....after I clean the HX tubes with a brush. I think the mechanical "action" inside the HX tubes just knocked some of it off. When I sent my sample in to Mike at Precision, he said this was no worries.

As for the rust on everything....I think that is normal as well. My guess is if you look it isn't really "rust" per se, but some kind of coating going on.

Feel free to post pictures, it always helps. But I suspect you are just fine, just nervous (as you damned well should be given the investment! We all know this all too well) Climbing inside and cleaning the debris off the floor might be a good idea...but it also might be "pointless" as well. This stuff will likely just sit on the bottom "forever". Once you have the preclean inside, I'm not sure what impact that has on human biology. Probably be fine...but you can also call Dectra just to ask.

There is also a thread from Rick here from last winter where he had serious biological rust going on....those pictures might help to give you a reference point.

Like you, I know nothing about boiler scale, boiler chemistry, etc. and without a reference point....one feels very uncertain.

More than likely, you can just fill and apply the initial chemicals...let it mix and burn for a bit...and then send off your sample. Precision has always been responsive...though again, I wish they'd supply some data from the past decade of samples to see where our individual points lie on the curve. Without a reference, it's just "worrisome".

But, so far, I've had no issue (that I'm aware). I do seem to go through the anode rod (my 1500 has one) in a year...curious....but I also made some grounding changes this fall, so I should lift the lid and take a peek.

Post some pictures, but I suspect you are just fine. Make sure you fill through the 5um filter Garn supplies. My fill was from my well, through my whole house filter, and then through the 5um filter from Dectra. Everytime I have looked inside, except for the white floaters after cleaning the HX, the water has always been crystal clear! White coating, especially on the HX tubes, is apparently commonplace. Not sure if my white flakes and "fuzz" are my Mg rod being consumed.

But I understand your apprehension! You are likely just fine.

Get ready to enjoy the beast....we couldn't really be happier.

 

[Karl_northwind]

We just installed our first Garn 2000 (as a contractor) and I really like it. our Customer does too.
we vacuumed out the inside of the tank and I'd recommend you do the same , maybe after this heating season when you can do it a little at your leisure. crud sitting on the bottom of the tank will hasten corrosion. it will prevent the treatment chemicals from getting to the steel and protecting it. This is almost verbatim what Mike at Precision Chemical told me.

would love to see some photos of the install.

karl