Making sure I get it...

Marcus Mead_4

Thanks to everyone who helped on my prior thread.



I now own Lost Art, and I'm ready for the final stage of my project, but I just need to make absolutely sure I'm understanding this-



1.  I've got a 1.5" main with a dry return- looks like (p. 90) I can use a 1" pipe for the dry return.  Am I interpreting that right?  Another site I found on-line had a chart that said 1.25, but that will double the cost.



2.  On page 85, it the main vent is at the end of the dry return- I thought it went at the end of the main.  Why would it go at the end of the return?  Wouldn't that just fill the return with steam that could be in the radiators?  (I'm sure Dan is right, but just want to "get it".)



Thanks,



Marcus

nicholas bonham-carter

where's main vent?

if you have a dry return on a parallel-flow system, then the vent should be installed at the end of the dry-return. it is most important to let all the air out of the system, even beyond the last riser up to a radiator. any residual air in a system can be a "wild card", or a raccoon at the garbage cans .

as far as the pipe size., is the recommended size so much more expensive? remember the dry return has to carry some old rust back from the radiators to the boiler, and therefore should be capacious. even 2X the cost, how does that amount compare with the monthly fuel cost?

don't forget while you are wrastlin' pipe, to make sure your pressure is nice and low [under 1.5 psi for reliability, or under 12 ounces for economy] , and your main vents are nice and big.--nbc

Marcus Mead_4

Pipe size

No I agree, I spent 10 hours digging this tunnel, I've come this far, I don't want to skimp on materials when I have to live with it for next fifty years.  I just thought that Lost Art was telling me 1", and those are $12.XX at home depot, vs $23.XX for the $1.25.  Knowing that bigger is only better if it's correct, I thought I would just get some clarification.



So 1.25 is the correct size for a dry return when the main is 1.5?



(and thanks for the easy to understand explanation, here in Michigan, the raccoon is our state bird, we know them well!  I'll put it at the end!)

Jean-David Beyer

Big Box Store

I am not a professional, but when I bought my house, I put in a darkroom with an elaborate sink. Vacuum breakers, pressure-temperature regulating valve, etc. All 1/2" copper tubing. I ended up with 100 soldered connections and no leaks. (The drains were PVC.)



I went to a big box store, no longer in business, and got a few items, but they did not even know what a vacuum breaker was. So I found a real plumbing supply house near me. Not only was their merchandise of much higher quality, but the prices were less than the big box store. So think carefully about going to big box stores for plumbing supplies.

Marcus Mead_4

Home Depot

Northern Michigan is actually pretty remote...  There is only one professional plumbing store, but they have very erratic hours, and close long before I could get there.  Home Depot certainly doesn't know steam, but they have the best price on black pipe in town, and cut and threat for free. 



But could anyone confirm for me the correct size for a dry return with a 1.5" main? 



That's what I really need to know.

Jean-David Beyer

plumbing supply hours

My plumbing supply house, in those days, kept what seemed to me to be to be very strange hours. IIRC, something like 6AM to 2 PM. But if I try to think like a heating contractor, that might well be reasonable hours. Get the parts needed before you go to the job. Pick up a few more at lunch hour, and by 2PM you will not be needing any more parts until the next day. I have never been a contractor, but I have watched many work.

Marcus Mead_4

And when I get there...

I will absolutely take your advice.



And when I get there, what size pipe should I ask them for, 1.25 or 1"?

Marcus Mead_4

I'm going with a 1" unless someone knows why not to.

Okay, Lost Art says a dry return should be half the size of main, but not less than an inch. 



I'm ignoring the chart on the other web site unless someone has a good reason not to.



Anyone? 



Thanks,



Marcus