Near Boiler Pipping Question

Luis

Please find attached pictures of the main vents. These things are HUGE and I have the cfm rating somewhere...

If memory serves me right, one of these main vents is equivalent to four "D"s.

Needless to say that Gorton builds an excellent product. Be ready to spend some $$$.

Luis

Near Boiler Piping (One-Pipe Steam System)

I've been working on a one-pipe steam heat system to rectify the "professional" installation which suffered from such maladies as bullnose tees, high pressure stat setting, etc.

I've installed a 4" drop header, verified the pitch in the mains, vented the mains, replaced all the radiator vents, installed a vaporstat, etc. Yet, I am still experiencing a heating problem: One of my mains takes considerably longer to heat than the other despite having equivalent pipe length, heating load, and double end-of-main venting capacity.

Looking at the main configuration, it daunted on me that maybe I misinterpreted what I read on Carrier steam manual; that suppy and take-off should be separated no less than 6" (which I have)and have short-circuiting between the boiler supply and one main loop which gets extremely hot very fast while the main second loop barely gets hot at all.

Looking at the attached pictures, the boler supplies are on the left followed by the main loop which gets really hot followed with the main loop which gets luke warm.

I am considering reversing the nipples of the second fitting so that the boiler supplies are closer together while increasing the distance to the take-offs.What should be minimum separation between boiler supply and take-offs?

Dry Steam

I'm certainly no expert, but I stayed at a..... No really I read that supply and take offs should have minimum 12" distance between them. Why? ask the deadmen:{)

Unknown

No insulation

Without pipe insulation, the load is almost doubled, and the pipes are still sized for insulated mains.

The number I remember is 5 times. A main loses 5 times the heat when it is uninsulated.

If the mains are losing 1/3 of the connected load in insulated systems, then the boiler output is 3 parts radiator steam and 1 part pipe loss steam.

If the mains are to carry 3 parts radiator steam and 5 parts pipe loss steam, the mains aren't big enough.

If your boiler was sized to a 1.33 pick-up factor (standard), and you are running uninsulated lines, (.33 times 5 = 1.65) you need 2.65 times the radiator connected load. Your mains will also need to be increased 2 pipe sizes in the whole building to make up for the lack of insulation.

If you didn't NEED the insulation, do you think it would have been installed with insulation? The insulated piping allowed them to use smaller iron pipe, as well as control overheating in the piping areas.

You need more steam or less piping losses.

Noel

Luis

Pipe insulation

As per feedback to my last post, I am insulating the near boiler piping, mains, and risers of my one-pipe system in efforts to obtain balanced heating throughout the house.

Having visited the local plumbing supply house, I found out that the counter personal had no answer to my inquiry as to how to insulate the fittings, but were eager to sell the standard fiberglass insulation and advised to leave all 45s, elbows, Ts, unions, etc uninsulated.

How can I insulate all the fittings? The system is comprised of 1-1/4", 1-1/2", 2", and 3" piping and associated fitings.

There has to be a way of using new materials, combined with experience, to duplicate the thorough insulation of all piping that the DEAD MEN completed with asbestos.

Any tips, tricks, product recommendations, that is type of insulating tape, etc would be greatly appreciated.

David Nadle

Fitting covers

Search the Wall for "insulation." You will find many threads discussing pipe insulation, what thickness to get, where to buy it, how to do the fittings, etc.

However, I do not beleive that lack of insulation is the reason one of your mains is only getting lukewarm. Are you sure those main vents are working?

Luis

David,

I am inclined to agree with you that If my both mains have the same equivalent pipt length and same heating load, that is, same quantiy of risers of similar equivalent pipe lenghts and radiator EDRs, steam still should reach the end of both mains at the same time. Yet, that is not the case eventhough the side that is the coldest has twice the venting capacity.

I observed the system yesterday...From a cold start steam reaches the header at about the same time from both boiler risers. However, from the header to the mains, the time lag to have both reach the same temperature is so great that the best way to convey it is to say that the wet return from the main that gets hot the quickest is burning hot and yet the coldest main is still venting.

I still would like to know what the minimum distance should be between steam boiler supply and main take-off.

I am considering installing vents along the coldest main as I believe that steam is being "sucked" by the main which is closer to the boiler supply - the one that gets hot really quick.

I look forward for comments.

Luis

David,

I am inclined to agree with you that If my both mains have the same equivalent pipt length and same heating load, that is, same quantiy of risers of similar equivalent pipe lenghts and radiator EDRs, my steal still should reach the end of both mains at the same time. Yet, that is not the case eventhough the sid ethat is the coldest has twice the venting capacity.

I observed the system yesterday...From a cold start steam reasched the header at about the same time from both boiler risers. However, from the header to the mains, the time lag to haev both at the same temperature is so great that the best way to convey it is to say that the wet return from the main that gets hot the quickest is burning hot and yet the coldest main is still venting.

I still would like to know what the minimum distance should be between steam boiler supply and main take-off.

I am considering installing vents along the coldest main as I believe that steam is being "sucked" by the main - the one that gets hot really quick - closer to the boiler supply.

I look forward for comments.

Billy_12

Here is a link to my insulation thread & where I purchased.
Is it possible that one of the mains is venting too fast or more than the other main, and the steam is taking the path of least resistance? (oopd, didn't see the previous post - didn't realize I was being redundant with this question)
Good luck

http://forums.invision.net/Thread.cfm?CFApp=2&&Message_ID=422715&_#Message422664

Unknown

for fittings, I use

I use cold water paste and cheeseclothes for insulation on fittings..

clammy

mains outta balance

i have run into this a few times your main which heats quicker probalby contains more rads or if all the vents are added up you will find that your quick heating main had a much larger venting capacity ,you should remove the main vent from that main and maybe add 2 main vents to the slower main ,it defenetly sounds like that's the promblem to me after the first time i encountered that type of promblem i now always check the edr connected to each seperat main and fiqure out how much venting is happening in each main ,also your system does have main vents correct?clammy

bob young

hey clamster

how goes it , bro. miss your imput & expertise. bob

clammy

thanks Mr.Young

As always Mr.Young enjoyable to see your post ,only good news is still veritcal ,work wise things are near impossible i,m at the point that i don't even bid most job because there 's about 10 other guys bidding and all are working for a days pays ,i,ve lately though been able to really see some old fashion across the street sizing and many 2 coupling replacements and no returning of phone calls ,I don't think any of this will get better unless i get a bail out which when i comes to paying bills i might be into if things don't get better ,oh yeah i started financcing also or at least that's what i call it when you don't get paid for your work and they send you 100 bucks here and there .sorry for the rant peace and good luck robert clammy

Luis

Thank you all for your input. I will post pictures of the end of main vents, but for the moment suffice to say that the coldest main has twice the end-of-main venting capacity as the warmest one. To say that the end of main vents are massive is an understatement!

I have calculated the connected EDR and air content on each main. I will look for the diagram an try to post in pdf format.

I've come a long way since I purchased the house - the water hammer days are gone as is the 5psi pressure control setting! However, I am not quite there in having the system "sweet" which I am determined to achieve.

To that end, I've replaced all radiator vents - Gorton, pitched the radiators, installed main vents - Gorton, built a drop header, replaced all near boiler pipping, modified the riser take-offs to 45 in lieu of 90 degree, installed a vaportat and cranked the pressure way down.

I am purchasing insulation and fitting covers that Billy has used. However, since I have done extensive work on the existing system, originally installed in 1930, how do you verify that there are no steam leaks in the fitting/pipe connections? I was thinking a soapy water mix sprayed in the connections would do the trick...

Which pipe dope is recommended? I've used the Blue Permatex thread sealant - great product, "el cheapo" gray Home Depot pipe dope, and the slighty more expensive teflon pipe dope from home Depot. I know, that the latter products may not compare to the former product, but when a 78 year old 2" elbow breaks at 8PM when you are trying to picth the main and you need heat, you consider yourself lucky to have a spare 2" cast iron WARD fitting, but no pipe dope. I placed cotton cooking string (had to improvise) coated with the teflon pipe dope between the new fitting and the existing pipe threads.

So, could someone advise on the proper technique to seal the threads, make connections between new and existing - read corroded - threads, and verify that the system is leak free.

Again, that your for the comments.

Bill_110

I'm having the same problem myself, though I am still at the stage of having the "professional" bullheaded take-offs and undersized pipes. On my installation manual it said to have at least 15 inches between the last boiler riser and the first system takeoff. A boiler piping tutorial also mentioned keeping at least 6 inches between the equalizer and the last system riser. You've probably already got it covered, but it might be worthwhile to check the slope of your actual header again to be sure it has a good grade towards the equalizer. One site I was on mentioned a header could be almost half full of water pulled up from the boiler. If your water was draining slowly into the equalizer that second system takeoff that wont heat as well might be pulling up more hot water with the steam.

David Nadle

Nice.

Now, when the boiler first starts steaming, how long does it take for the two vents on the cold main to get hot? Should be just a few minutes. Make sure the vents are actually venting. You should be able to hear and feel the air with your finger near the hole.

JBee_9

Pipe insulation

http://estore.websitepros.com/1805348/-strse-PVC-Fittings/Categories.bok Please click on pipe insulation on the left for your pipe sizes. This was on the wall a few days ago.

nicholas bonham-carter

the ultimate vent..

can you arrange the no-vent test, to see if venting capacity is realy the problem? it's best to stick a ball valve on each vent tapping, then fire the boiler with the valves open until steam appears.close the ball valves, and then see if the steam has filled each main at the same speed.this will confirm or deny the venting question.other reasons for slow steam could be sagging pipes which allow an anti-steam dam of water to form.check then with an accurate magnetic pipe level.--nbc

MrPE

No vent test

Nicholas,

I will be doing the "no vent" test this weeknd and post my results. I have access to a unit that can record temperatu measurements in congigurable cyclical intervals so I can substantiate the time differential between gettting stem to both end of mains.

I also read your post on cleaning the system and have reviewed Dan's book on the subject. A main steam shut-off, like installed by Mad Dog, is recommended so that the system can be steam cleaned, right? If do, which valve, i.e., manufacturer do I purchase for this purpose?

Thank you