Greenwood Transfer Fluid

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Trzebs13 said:
jbeamer said:
To Trzebs13 - if I crack the safety blow-off that you pointed to in the pic, where can I expect the fluid to come out from (sorry for the ignorance). Also, you mentioned the air separator - are you able to point that out to me? BTW, the transfer fluid they suggest is the glycol mixture you mention.

The saftey blow offs do one of two things. Either it opens that valve under pressure. Meaning if pressure builds in the system too high it will open that valve to release that pressure so it will not gernade. Or it will open by tempature. I thought most had 1 of each on them. You want to test these at least once a season to ensure that they are not corroded shut, keep them working properly.

I have marked those pics with your answers.

And are those just hose clamps on your pex lines going out?? That in my book is not kosher. You have a pressuredized system of very hot fluid flowing there. Have a plummer stop over and have him replace those with some pex crimp clamps.

I would not worry about that plumming haveing some rust, iw will take a good amount of time for it to compermise the strenght of those fittings. But I would look at the air cerculation in that room. During the summer is it able to breath or is the concrete just sweating like a pig and eating away at your boiler.

As far as the skins Jimbo just went threw this with his. But I'll throw my 2 cents. Mine has Stainless Steel skins. If I were to work on yours I would definitly reccomend that you do SS. The one thing I don't know is the cost difference here. You should be able to handle changing these your self. Find a Fab shop in the area and probably the best is to take the rusted skins there and tell them you need a new pc like this. Or take measurements and thickness and they could probably shear one up. It's just a flat plate. The only tricky thing here is attaching the insulation. And Jesse had some good idea's on that one.

Stick with it, a little work here and you'll have a great boiler that will keep you cozy and warm for just the cost/labor of your wood.

Trzebs13 - sorry if this sounds like dumb question, but...if I hook up a hose to the drain valve as you mentioned earlier, is there a way to know when the water has reached the air separator?
 
Alot of these style boilers come with the 30# pop off valve and the T&P Valve. I don't use the T&P valve. I constantly run my system over 200* and I could not do that with the T&P. JBeam, don't worry about what your GW Manual says. If GW manuals are like the Setons and Greenfires (both of those names are similar style boilers to your Greenwood) they cover many different install installations and you were probably looking at an install that does not apply to you.

I can see you are getting overwhelmed with information. Like Jimbo said (oh BTW we call IseeDeadBTUs - Jimbo) you have come to the right place for info on your GreenWood. We are a very involved group, many of us have rebuilt and retrofitted our GreenWood style boilers. That said, I think you should only concentrate on 2 things right now until you learn your system better. 1. Assess whether or not you can get another season out of your skins. 2. Regardless of what you do with the skins, you should take a side off of your unit and give the Hex (heat exchanger- all the tubes you see at the top of the boiler inside) a thorough cleaning. You may want to ask the former owner if they already did that this year or the end of last season. I doubt they did because you said you can see creosote. If you can see creosote on the top tubes - then the tubes in back are probably plugged real bad. There is a link around here that will show you how to take a side off and clean the hex.

Don't let all this overload of info discourage you. Once you get by the first few hurdles, you will be happy with your wood boiler. They make alot of heat :) Oh one more thing. These style boilers really like large - unsplit rounds. Split wood will burn too fast and burn dirtier, strange but true.

Good Luck, Anything you need to know about your GW can be found on this web-site!!
 
ISeeDeadBTUs said:
Ok, I'm gonna chill 4 a bit and let someone else give you their ideas.

If money were no object, I'd yank that GW and replace it with a tried and true unit that is designed to be used in a closed system. And I'd either incorporate storage, or make it so I could seperate the wood unit from the oil unit durning the DHW season.

If money were somewhat of an issue, I'd seperate the GW from the oil, burn oil for now. Then I'd disassemble the GW and fix it properly.

If money were the only issue, I'd find all the current jobs that contractor is working on, then tell the contractor that, unless he gives you the $4k back, you are going to show pictures of the plumbing to all his customers :smirk:

Okay, money is an object so we won't be replacing it anytime soon (I just wish I had understood what I was getting myself into at the time). It's my understanding that this unit is designed to be used in a closed system. I can easily separate the boiler and the oil systems at any time - I have valves in my basement that shut off the water flows to the outside furnace. And, as far as the plumbing is concerned - I think he had someone else install the unit. He built the home we are in and he was very meticulous about everything (didn't cut corners, beautiful design, lots of "extras")...so I find it hard to believe that he would have cut corners for the stove.
 
sparke said:
Here is the link that shows in detail how to remove a side and clean the Hex:

http://www.thiswarmhouse.com/_files/ManifoldInspectionAndCleaningServiceBulletin.pdf

This is a thread from another member that tore the unit apart and cleaned it. Hopefully your is not as dirty as his was!

https://www.hearth.com/econtent/index.php/forums/viewthread/17139/

I really appreciate your feedback, as I have definitely been overwhelmed the last day or so with all of the potential fixes my stove may need. Thanks for the links on how to clean - it looks like I have a weekend project ahead. You mention determining if the skin has another year of life to it -- is it a matter of determining how the inside looks? I know there is some rust/bubbling on the back panel externally, but if the inside of this same area looks good then I'm assuming I can burn for another year. Does that sound like a feasible plan?
 
quote]Trzebs13 - sorry if this sounds like dumb question, but...if I hook up a hose to the drain valve as you mentioned earlier, is there a way to know when the water has reached the air separator?[/quote]

Almost every system is installed a little different from what I have learned. The reason I refered to my air seperator being what I left off during filling. Was because it was the highest plumbing point in the system. Looks like yours may be somewhere around the expasion tank. The idea of filling these closed loop systems is that you fill from the low point up to the high point which forces most of the air out to begin with. I say most because there could be a small amount of air that gets trapped in a bend or something. That is was the Air seperator is for. As your pump forces the water threw the system is will work out that air and then get seperated out. So just keep that in mind that you fill from the bottom up and you'll get most all of the air out.

BTW the air seperator will make a pssssssss sound as it expells any air in the system and will stop when all of the air is out.
 
I am not sure how to determine if they can make it another year. I have SS skins so I don't have this issue. I think common sense goes a long ways. If the inside is not corroded and you cant poke a finger through the bad spot, go for it. Just keep an eye on it. Maybe someone else with experience with the corrosion can give you a better way to figure out if your skins have any life left. If it just surface rust you may be good for a few years...
 
Hi guys,
I have been running Camco Boiler antifreeze for three seasons with no corrosion issuses. My system is an open system with a recovery tank that I made from a 55 gallon drum. Everytime I check the fluid in the tank and drain some from the system it looks pretty clean and still red in color. I ordered it through a camper dealer. It is the pink stuff that is bio degradable for campers but made for boilers and supposedly has a rust inhibitor in it. So far so good.
 

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Just a test to see if I could submit a picture. This is what I am heating........
 

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WoooHOOOOOOOOOO! I did it! my first resizing and pixel adjusting attempt on the site. Sorry for my arrogant excitement but I am a computer moron.
 
Let's not cofuse the OP . . .

the corrosion does NOT come from circulting fluid. The 'heat transfer fluid' does not come in contact with the skins.

Opinions, as they say, are like buttholes . . .here's mine . . .

the corrosion seen in your pics, jbeam,started from the inside, not the outside. The outside was painted at the factory, and seem to hold up well. The inside of the skin is unpainted. Since the first fire it has been subjected to caustic water. It has been in nearly constant contact because the insultion holds it aginst the back side of the skin. I have never seen skins as bad as the ones in your pics. If someone else here has posted worse pics I've never seen them.

As far as WHEN to replace the skins, look at it this way:

Right now the day temps are nearly 50, the night lows are low 20's
Mid winter when the flames shoot out of the skin and you have to shut down the daytime highs will be mid 20's and the nighttime lows in the single digits.

Figure 36 hrs to cool the unit down, 48 hours to diassemble, fab, reassemble, refire.

When will you use more oil?
 
Jimbo you are absolutely correct - if they need to be changed they should be now as opposed to middle of winter BUT, how do we know the corrosion in the picture is from the inside out? I was wondering if the lines were leaking causing surface rust? That said, you are probably right and a benefit of changing the skins now would be a great time to thoroughly clean the Hex. JimBeam , keep us posted as to what you end up doing. We like pics : )

9122 - Nice looking Colonial house? I heard it is hard to heat houses with an exterior like yours but I assume that is because houses old enough to be built like yours have poor insulation...
 
More questions . . .

What is on the top of the GW? From the pics so far, it looks like something has been laid over the top of the top skin.

How are the nipples? One place that corrodes incredibly fast on these units is where the iron nipples protrude through the skin (Top and Back). And it's not the skin that wears out it's the iron nipples!!



And now, more of a general question for the professionals and those who run a wood hydronic in series with an oil boiler . . .

When the water comes out of the oil boiler, what temp circulates to and through the wood unit? I ask because my oil unit has outdoor reset. Which means that only on wickedly cold times will she ever be at 180 °F . Are you guys not circulating back to the wood unit during shoulder and summer?

Jimbo
 
The grey "covering" you see on the outside of my stove is some kind of insulation - it is a thin piece of paneling with insulation between it and the actual furnace. It's on the top and both sides.

I am dismantling the stove tomorrow to have a look inside and clean it thoroughly. I should have a good idea as to how the inside back skin looks after tomorrow. I'll post pictures. I am not opposed to getting everything cleaned up and looking good again before firing (you've all convinced me of this). What's a little more $ spent on oil?! I just have to find someone who feels comfortable working on the plumbing of the GW. Although a lot of people around here have stoves, no one knows much about GW.

Here is a question that I'm still trying to figure out with my GW. Does the "transfer fluid (in my case, probably water)" circulate only around my stove, or does it travel all the way into my house and into my oil burner and then back? It's my understanding that the transfer fluid stays in/around the stove itself and transfers the heat to the water that is being pumped in from my house. However, I've had other stove owners think that this is incorrect. I guess I'll see for myself tomorrow, but perhaps someone could set me straight.
 
With out reading the whole thread again, I believe we came to the conclusion you have a closed system. If there is no heat exchanger anywhere between your GW and your oil boiler you have just water from the heating system. I.E. water from your oil boiler and baseboard/radiators. The water circulates between all devices on your system. The only water inside your GW is in the tubes we talked about (Hex). You are going to be surprised how this stove is made, don't let it discourage you but your first thought when you take the skins of is holy chit there not much between the fire and me. Be prepared to get very dirty and you will most likely have to replace all the insulation. You can get it at a local heating store, FW Webb, etc... You will need Roxul (brand name for mineral wool) and some ceramic blanket. If you cant find local, you can order from: http://www.mcmaster.com/

As far as plumbing you need to find a shut off before and after the GW so you dont drain the whole system. Good luck!!
 
When cleaning the internal pipes, do I need to have the flare brush that they talk about in the service bulletin (it attaches to your drill), or can I just scrape off the creosote with paint scrapers? Do I need to be careful not to scrape too hard, or are these pipes nearly indestructible?
 
Just for weekly cleaning of the lower tube I attached a wire brush to a long piece of pipe and can reach in fire box area and give it a quick brushing before loading. I cant reach the upper tubes with this but thats what my side access panels are for. Good luck
 
I thought I should post the results of my cleaning efforts today. A friend (who has a lot of experience with stoves in general, although not a GW in particular) helped me open the furnace. We did a lot of scraping and filled a garbage can about a third of the way full with creosote and ash. It was very evident that it had never been apart. We didn't do much damage - a broken eye hook because it was so tight, some slight warping at the edges of the side skin because the tape holding it down was so tight, and some torn insulation between the skin and the bricks. Fortunately, with a lot of patience, we were able to get the kaowool and insulation back in place without having to replace it (will likely replace it next time). The back skin damage seems to be superficial - likely the result of a water leak from the pipe. The first two pics are before, the next two are after, the cleaning.
 

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Trzebs13 said:
Not to many of us use anything but straight water for the " Heat Transfer Fluid ".


Quick question for you guy's that run water. Do you add any kink of treatment? And if not do you change it? I went with the glycol because I wanted the protection and also was told that if I did that I would never have to change it out. Not really sure that is or is not the case? Thoughts anyone?

I was wondering that too. My friend says to use Distilled or Reverse Osmosis water. Most tap water is full of lime and other minerals that will damage it. Furnace Filters
 
jbeamer said:
I thought I should post the results of my cleaning efforts today. A friend (who has a lot of experience with stoves in general, although not a GW in particular) helped me open the furnace. We did a lot of scraping and filled a garbage can about a third of the way full with creosote and ash. It was very evident that it had never been apart. We didn't do much damage - a broken eye hook because it was so tight, some slight warping at the edges of the side skin because the tape holding it down was so tight, and some torn insulation between the skin and the bricks. Fortunately, with a lot of patience, we were able to get the kaowool and insulation back in place without having to replace it (will likely replace it next time). The back skin damage seems to be superficial - likely the result of a water leak from the pipe. The first two pics are before, the next two are after, the cleaning.

Nice Job!! that looks like you did a great job cleaning. Not to scare you but that is the way mine will look come spring when I do my yearly cleaning. I have seen some pics around here that had much more build up then that. I remember seeing one unit that the entire top, of the top row of tubes were totally filled with build up. But the first two pics is what mine normally looks like after a season.

So what kind of tools did you find to work the best for you?

And a side note, I would think some one that knows about hot water heating in your area could help you with your plumbing issues. Looks like you just need a few things fixed up and you should be ready. (getting rid of those hose clamps I would think should be high on your list)
 
Excellent job JBeam!!As 13 indicated, if that's never been apart, it didn't look too bad. It now looks much better.

It looks like you scraped the refractory. I'd suggest in the future not doing that. When she gets up to temp, there will be NO black anything. Hard to believe, especially by those with steel primary combustion chambers, but true. The refractory gets so hot that nothing sticks to it.

About that superficial rust on the back skin . . . I'd recommend keeping a close eye on that all winter. It seems unlikely to me that a water bath from the out side on a pinted surface that is vertical would cause that.

A couple of pic requests . . .

Can you shoot some of the outside of the top and side skins? We'd like to see what they look like after being wrapped in that grey stuff. Also can ya shoot some of the grey stuff? How did the grey stuff hold up during disassembly and reassembly?

And again, great job tackling this! Once the plumbing is fixed and you fire up, this definitly qualifies you for an adult beverage of your choice!!

Jimbo
 
I don't have time to shoot pics of the outside right now, so let me describe it to you. The top skin and front look factory new. The back has the paint issues/rust which seem superficial. The left side (the one we accessed) has a large spot of discoloration suggesting a hot spot at some point. Didn't look at the right skin. There is a layer of fiberglass insulation that is draped over the whole stove (from one side, across the top, down the other side). The grey board that lays overtop seems to be some kind of ceramic product - it is essentially just holding the insulation down and is not firmly attached to anything.

My friend thinks we should keep a close eye on the back and on the hot spot area. In addition, he doesn't seem to be concerned about the plumbing quite yet (although the pics look rough, the rust is very superficial).

My current thoughts/plans are to fire it up and keep an eye on things. If all goes well, I will plan to replace skins and pipework next summer when I shut it down. I won't be able to do this stuff on my own.

Does that approach seem reasonable?
 
Jbeamer,
If it is not to much trouble could you accurately measure the dia. of the heat exchange tubes that you scraped. I have an Idea of taking a large fender washer with the same inside dia. as the outside of the tubes, cutting the washer in half and welding it to a piece of round stock to use as a handle. the "C" shape of the washer may work as a good scraper while the unit is hot. I meant to measure it myself but now that my unit is 1000 degrees inside it might be tough to do.
No problem if you can't measure it just thought I would ask?
Rich
 
91220da said:
Jbeamer,
If it is not to much trouble could you accurately measure the dia. of the heat exchange tubes that you scraped. I have an Idea of taking a large fender washer with the same inside dia. as the outside of the tubes, cutting the washer in half and welding it to a piece of round stock to use as a handle. the "C" shape of the washer may work as a good scraper while the unit is hot. I meant to measure it myself but now that my unit is 1000 degrees inside it might be tough to do.
No problem if you can't measure it just thought I would ask?
Rich

I'll do this for you, but it probably won't be until Wednesday, if that is okay.
 
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