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[ST98]

Afternoon all, I have a question about going 1 inch to 3/4 out of the HE. I'm going to bring 1 inch to the HE from the OWB. Then run out to two 100k garage fans. Each will have its own circulator.  My buddy has the same set up. When he came out of the HE be went to all 3/4 to the blowers. I was going to use 1 inch thinking more flow would be more heat. I don't mind the extra few dollars for larger valves, lines, fitting, etc. am on the right track or does it matter?  They are 100' round trip from the blowers with eight 90,s. 12' vertical head and was thinking of running them with a taco8.  I may be overthinking this but I do a lot of friction loss calculations on fire hose the same size and it matters quite a bit.

Any thoughts would be great.

Thanks

[Scott7m]

Yea...  Hmm..   I don't see any reasoning behind going with 3/4". 

What are you trying to accomplish? 

When you say both 100k heaters have there own circs? But from what, from the boiler, a heat exchanger?

How many things are on each loop?  Are there more than one loop? 

Just trying to understand what's going on

[ST98]

I'm trying to accomplish the most heat to each unit. Both are on there own circulater from the heat exchanger. Two loops one for each 100k unit. Also a very small baseboard loop from a different circulator from the he, maybe 10 k at the most.

My question is it better to spend a few more dollars to go with 1 inch or does it matter at all and just go with 3/4"?  All this is from the he to the blowers. Nothing with going back to the OWB.

All this would go from the he to a manifold to the pumps and then out.

Thanks

[Scott7m]

As long as you have plenty of btu available the 1" lines are definitely worth it, they'll flow twice as many btu as 3/4" lines.  Doing it more efficiently, to move the same amount of btu through a smaller diameter line would require more energy as well

For example if you see a het exchanger rated at 100,000 btu.  That's at a certain gpm, and if it has 1" ports then it was likely tested with 1" lines hooked to it. 

Bottom line is yes the 1" lines are far superior to moving btu's vs. a 3/4"

[ST98]

Thanks Scott. Seemed to make sense but I needed a professional to keep me straight.  I'm still attempting  to design everything so it's somewhat right and this info sure helps.

[Scott7m]

Yep, good luck!!!   

[ST98]

I've have another question (many more to come) can you use galvanized pipe in a heat system?  I was going to make a manifold out of it, I have lots of new galvanized fitting of all kinds, but did t know if it was good or not. My furnace seems to have a mix of black pipe and galvanized in its manifold.

Thanks

[Scott7m]

I've seen galvanized used, it's just a coating...   Typically the galvanized fittings are cheaper made though, so it's up to you. 

I used to use them on water plates when going from 1" to 3/4" to tie into domestic lines and they all rusted up really bad.  Looked like crap and started to seep, so I'm not real crazy about them but like I said I have seen them in use in other situations. 

A nice brass header sure would look nice   

[slimjim]

Copper and brass, take your time, hang the manifold on the wall away from the boiler for easier servicing of the oil boiler, do it right and you will be proud of it.

[ST98]

I have a stainless manifold that's new. It looks pretty nice. Would that work or is copper or brass better? 

I'm a little confused about the temps for oxygen barrier pex tubing. If my OWB is set at say 190 or even 200 I would need a pex inside the building that met the same temperature rating?  I was looking at pex and it seems it comes in 180 or 200 temp range. The only difference seemed to be a double in price for the 20 degrees. I'd like to do this install once so I wasn't sure if I was looking at the whole pex thing right?

Thanks

[Scott7m]

Look t the details, that rating in pex is at 100psi

[ST98]

Thanks Scott, two were listed differently. Any recommendations on a brand of 1" pex. I used 3/4 last week for the first time and it wasn't to bad. Thinking 1" I'll need to eat my spinach.

Thank you

[Scott7m]

Shark bite or Watts are good

If you wanna spend a little extra pex al pex sure looks good inside because you can bend it and it will stay bent how you want due to the aluminum

[CountryBoyJohn]

Home depot has Sharkbite blue and red pex for sale for $57 per hundred feet.  Lowest price I've seen anywhere.  Free shipping too!

http://www.homedepot.com/p/SharkBite-1-in-x-100-ft-Blue-PEX-Pipe-U880B100/202033015#.UinPNxukq1U

[slimjim]

Come on, you spend good money on your tractor and chainsaw and are thinking about cheaping out on your heating system, Pex Al pex is not bad quality stuff, not what I use on the job but definatly better than that spaghetti crap they sell at the box stores.