main vent HELP

Erik_M

So I set out this morning to clean 2 of my main vents that have been leaking steam.  First vent came off easy, the second vent though did not.  The vent was in a tight spot next to a floor joist at the end of a horizontal main (see blurry photo), and was plumbed off the end of the main with a couple of reducers and a 1/4" elbow.  With no room to disconnect the vent by itself, I tried to disconnect at the reducer.  With barely a twist it broke clean off at the threads of the reducer (see photo).  Now I'm left with a roughly 1/2" opening at the end of one of my mains.  Two questions . . .



1)  Until I can get this fixed in a few days (either by me or a pro), is it best to leave the hole open, or should I plug it with something?



2)  What brand/size vents should I buy to replace these?

      -  Vent-Rite No. 75

      -  No. 1 Hoffman Siphon Air Valve (this puppy is circa 1917)



THANK YOU!



Erik

Erik_M

FYI

Photos 4 and 5 should be rotated clockwise 90 degrees to be viewed correctly.

Jamie Hall

Ah...

if that busted vent connection really is on a steam main, and not a dry return which is known to be protected by working traps or well calibrated orifices, you've got to either plug the hole or get a vent on it, and "now" is a little too late.  You really don't want live steam hanging about in your basement...



As to what to replace those vents with... what size (length and diameter) main are we talking about here?  That will get the amount of air you need to get rid of, which will lead to the vent size...

Rod

Main Vent Sizing

Hi- As Jamie has mentioned you need to plug the hole as having steam filling your basement isn't a good idea,

Your present main vents are on the small side venting capacity wise. Let us know the size of your piping and the length and we can calculate how much venting you need and what make and model vent is appropriate.. The pipe size needs to be accurate but the length can be a "guessimate" as long as it is with in a foot or two. Use the piping chart attached below and measure the circumference of the pipes and compare it the chart to determine the pipe size.

- Rod

Erik_M

thank you

Thank you Jamie and Rod.  Will post the size of the mains in a few days. 

Erik_M

Measurements

Took some measurements this evening and put together a crude schematic of my pipes in the basement.  Hopefully I have all of the important dimensions.  From what I can tell, two of the vents are on the return piping at the end of each main, and one of them is at the end of a really long branch line.  I've included a photo of the boiler piping (pipes will be insulated soon - that's my next project), a photo of the two vents on the return piping, and the vent at the end of the branch line.  Thank you all in advance for all of your help.  It's very much appreciated!



Erik

Rod

Main Vent Sizes

Hi Erik-

  Here's what I worked out for your main venting needs. (See attached drawing)

  Vent AA  - 1 ea. Gorton #1

  Vent A     - 2 ea.Gorton #1 s

  Vent B     - 2 each Gorton #1 s

For mounting Vents A & B I'd use a tee on the end of the present vent pipe and then using a 90 degree street elbow on each end of the tee and mount the vents on each elbow.

   Bellow are the calculations for the venting. I included the figures for your old vents. You should notice an improvement in your venting,. Keep the old Hoffman #1 vent. It's a antique!

You should be able to get Gorton Main vents from a local supplier or they are available on the internet from Pex Supply. http://www.pexsupply.com/

- Rod



Main “A”       2" pipe        =   33 ft.     x  .023     =   0.759 cu.ft.       

                                                              Vent A =   2 ea. Gorton #1                     



Main”AA”    1 ½ “pipe     =   11.5 ft.  x   .014     =   0.161 cu. ft.

                      1"  pipe        =   12 ft.     x   .005     =   0.060 cu. ft.

                                                                                     0.221 cu.ft      

                                                             Vent AA = 1 ea. Gorton #1



Main “B”       2.5 “ pipe    =   11 ft.     x  .030      = 0.330 cu.ft.

                       2 “ pipe       =   26 ft      x  .023      = 0.598 cu. ft.

                                                                                  0.928 cu ft.

                                                              Vent B = 2 ea. Gorton #1



Gorton  #1 = .330 cu.ft.per min @ 1 oz per sq in.

Gorton  #2 = 1.10 cu.ft per min @ 1 oz.per sq in.



Old Main Vents

Vent Rite 75 = 0.116 cu.ft per min

Hoffman  #1 = 0.016 cu ft per min.

BobC

maybe?

If that one 1-1/4 main that Rod referred to as "AA" is really reduced to a 1" after the first radiator pipe it may be too small to feed the 2 other radiators; maybe the second radiator on that 1' run was an add on later in the life of the house. That pipe is really a counterflow main and it (1" pipe) is rated to feed 28 sq ft of radiation; the initial 1-1/4 pipe to the first radiator is rated to feed 55 sq feet of radiation. All of this is from pg 89 of "The Lost Art of Steam Heat" table for a horizontal run out where the main is not dripped (counterflow).



This may well work just fine if those two radiators are small and the Gods are smiling but if you have any heating or banging issues with those two radiators that 1" pipe might be the problem. On a vertical run that 1" pipe could handle 45 sq ft, I don't know what part of the run is horizontal and what part might be vertical.



In any case if those two radiators have no issues you are probably fine with things as they are.



Bob

Erik_M

THANK YOU

Wow.  Rod, your reply is tremendous.  Can't thank you enough for taking the time out of your evening to help me out.  I'm looking forward to getting those new vents on and seeing the difference they make.



Now if I can only get that dang iron pipe apart!  I still haven't been able to get the reducer out of the elbow at the end of "AA" where it broke off at the threads when I removed the old vent (photo #5 in original post).  I've heated it up, I've tried "PB Blaster", and it just won't budge.  Any tips?  I've tried going for the 1" elbow as well because I can get a better purchase on it, but that won't budge either.  Doesn't help that there's virtually no room to work. 



BobC, thanks for your reply as well.  Looks like I made an error on the diagram and there's actually just 1 radiator past the point where "AA" reduces to 1".

Erik_M

How do I fix this?

In the photo below you can see the end of the 1" main (the one we've been calling "AA") where the old Hoffman vent broke off.  That's a cork (yes, a cork) that see you see plugging the end of the pipe now.  I still haven't been able to disconnect the old pipe to install new fittings and a new vent. 



I've tried disconnecting at points A, B, and C, with no success.  I've used a torch, I've applied penetrating oil for several days, I've hammered the fittings and I've used cheater bars and everything else at my disposal.  I would use a sledge hammer (or 2 ball peins as I've read about) to shatter the pipe at a fitting, but there's no room for that.  The pipe is between a floor joist and a rim joist, and access is limited from below by a drain pipe and two water lines.



Can anyone recommend another solution?  If I cut the pipe somewhere (further back if necessary) is there a type of union fitting I can use to connect to the old cut pipe to a new one?



Short of any new ideas I'll be calling a pro.  Just haven't pulled the trigger yet with this warm weather we've been experiencing.



Thank you.



Erik

Rod

Removing the pipe from a fitting

Hi Erik- From the picture, it's hard to tell how much clearance there is around the piping and having working room would be the biggest factor in choosing which fitting to attack.  First of all do you have a sawsall ?    Where is the last radiator lateral and is it in a better location accessibility wise?  I'm thinking it might be a better place to work.

      Basically what  you will need to do is saw off the pipe about an inch from the fitting and then cut the pipe from the inside. (out towards the threads)  You want to make several cuts and then collapse the pipe away from the threads.(Use a cold chisel)  When you're sawing try to not saw the thread in the fitting. If it does cut thorough a bit it will probably okay just that you should try and avoid cutting the threads if possible.. If you don't have a sawsall I'd get a pro to come out and do it for you. If you do have a sawsall you might want to check as to whether the blades you have,have clearance to cut inside the pipe.

- Rod

Erik_M

Yes

Rod, I do have a sawzall and there is a radiator lateral about 6' back on the pipe.  It's also impeded by the same drain pipe and water lines, but in a slightly better working location.   I will see if it's accessible with the sawzall this weekend.  Now that I understand the technique you described, I should be able to make my new connection at some point along the line.  I'll let you know how I make out.



Thanks for your help!



Erik