The Price of Copper

[RobC]

In the beginning of the thread there was a question about circulators pumping through each-other. That does work. I'm pumping through a Taco 007 and doesn't seem to effect things. There was a comment about the close proximity of the 2 circulators,. That I don't know about. Someone way back had called Taco and talked to a rep and they said no harm would come and there would be very little restriction.
Nice soldering....

 

[woodsmaster]

went to get a roll of 12 -2 wire yesterday and seen the price went up about $6.00 a roll. Wonder if pipe is soon to follow ? Seems someone posted last fall that the price was going to go way down. Pat mabey ?

 

[slowzuki]

From the number of copper thefts lately, I'd say the price is back up.

 

[Chris Hoskin]

Hi all, interesting thread. Just wanted to mention that it strikes me that all of the submerged heat exchangers (and your flatplate, Eric) seem quite undersized. For example, we would specify THREE of the 180' STSS coils to be used with a 60kW boiler like Eric's EKO or our Solo Plus 60. Remember, you are sizing the heat exchanger to the boiler output, not the heating demand of the house. I have not personally done the calcs, but I know the sizing is based on the difficulty of heat exchange into a tank when boiler and tank temps are close to one another (low Delta T). Coils should be plumbed in parallel, not series, by the way.

As you can see by the cost of these coils, there is good reason to consider having one set of coils act as both charging coils and discharging coils as shown in our drawings ("Square Tank", for example). A bit more complicated on the controls side, but saves the cost of a second set of coils and allows you to send heat straight to the zones if tank temps are down. In other words, the heat from the wood boiler doesn't have to go 'through' the tank to get to the zones, so you don't have to wait for tank temp to come up before you can get usable heat to the zones.

hope this is helpful

Thanks... Do you have a link to the "Square Tank" arrangement you mentioned?

See pages 16 and 17 (depending on boiler output) of this document: http://www.woodboilers.com/admin/uploads/public/WoodBoilerPlumbingSchematic1110Web.pdf

also read Appending F to see how all the components work together. Let me know if you have any questions.

Chris

 

[Ryedale]

Found some 1" type K coils on Craigslist yesterday, and drove to get them last night.
I picked up all that I should need to charge my storage tank 400' I got it for about half the shelf price woohoo. Menards price is $5.21 out the door right now, this was $2.60, much more tollerable for this important part of the system. This savings will pay for my chimney, and most my underground Thermopex.
The stuff is a little corroded on the outside (green dust oxide) but largely it's great. Still in original boxes but the boxes were ripped opened so the copper was exposed here and there.
I'm going to shine it up with some Con-Coil (coil cleaner used in the HVAC industry)
Planning on going with the SSTS coil arrangement, two coils about 180' each or I might just use the full 200' for each one. 1 1/8"OD (1"ID) has about 30% more surface area over 7/8OD (3/4"ID) per my primitive calculations.

The guy said he might have some more rolls if anyone is interested. I told him I wished he had told me before driving out, I would have bought it all knowing how valuable this is right now. I think he could have scrapped it for more than he sold it to me for.
He said they are out of the box, in a little rougher condition, but that should just be surface corrosion. This is 1 1/8 OD 1" ID, Let me know if anyone is interested.