wet steam /vent spitting

Frostman

I have ONE radiator , out of 6 spitting water. The room had no Rad, in it so I reinstalled one. All the branch piping to the rad has been replaced, but is original size. Only recently has the "spitting" been an issue. I understand the importance of near bolier piping in drying out the steam. Is it possible that just 1 Rad. and not all would "spit" if the near boiler piping is too small ? There is only one main vent in the basment for this system, even though it splits off the supply riser into two feeds, running front and back of the house. That vent is on the "front" side of the supply, and I have no isues with those rads. There is only 1 other rad on the "back" side of the supply, it is further away from the boiler, but has less piping to it, then the problem rad. The boiler is a gas fired weil-mclain gs 35 .

BobC

Add a vent?

What kind of vent are you using on the spitting radiator? A fast vent can make spitting easier. Make sure the piping that feeds that radiator has good pitch back to the boiler and make sure the radiator itself is pitched back towards the supply pipe. Is the piping insulated?



If the near boiler piping is not correct in size and configuration you could well be making wet steam. The one additional radiator should not change things as long as it's not a very large one. Adding a vent onto the main that feeds that radiator can only help matters. If there isn't an easy spot to add one you could drill and tap the pipe near it's end for a 1/8" NPT  radiator vent (Gorton D?) to add a vent.



Bob

Frostman

wet steam/vent spitting

Thank You Bob . I will check the pitch on the branch piping as well as the rad. itself I'm comfortable that it's ok but never hurts to double check. As for the near boiler piping,it's been there since I re-installed the new rad and this problem has just started in the last week, even though I installed the rad, 4 years ago. The pipes are insulated,owen's/ corning type, not foam rubber.

As for the main vent, there is one right above the boiler where the supply splits to the front and back steam main, should I install a 2nd main vent at the same location for the "back" steam main, or is it best to install a main vent right at the end of the "back" steam main just before it dropsi nto the return pipe? If I do drill & ap in the new location, is it best to install the vent (wich type?) on a riser or right into the main trunk ?

The Rad vent I installed is the adjustable type purchased at home depot, not the round 'hockey puck" type that was on the rad.

Thanks for your help . I have read both "The lost Art of Steam Heat" & "How To Get he Best From One-Pipe Steam" and I still have questions.

BobC

Pictures

I'm having trouble visualizing your piping, can you post pictures of where the boiler connects to the mains and the current vent location?



We have had a very cold winter and I suspect frost is pretty deep and that may have moved the ground enough to take an iffy slope and make it bad.



Bob

Frostman

wet steam/spitting vent

Update, I was at the house yesterday, the rad. has pitch, the bubble just breaks the line on the level, the branch arm has plenty of pitch and is well insulated. The supply for this rad. is coming off the run of a "tee" that feeds the kitchen rad. I installed a Maid--Mst "C" vent on the rad. In the basement the steam supply trunk has good upward pitch and the return trun has good downward pitch.

There is 1 (ONE) Vent-Rite #35 vent on the reurn side just at the boiler where the 2 (two) returns meet at the boiler. This vent is on the "front" supply loop, the rad. in question is on the "back" supply loop One thing I also noticed, the newer copper near boiler piping up to the original iron supply header tees into the equalizer at just about 24" above the center of the sight glass. If raising this piping up will make dryer steam I can do that prett easy. The tapping is 2" and the original header is also 2", is there any benefit to increasing the copper piping to 3".

There are no vents (main vents?) on the supply loop in the basement, You can see there is 1 on the "front" return and I can install one on the "back" return, unless putting the vents on the supply side at front & back is best.

I was also able to put a lighter next to the rad. vent tapping and saw pretty active panting. My understanding is the 1st thing to do is get rid of the wet steam, then worry about main vents.

I hope these photos might help.

Frostman

Correction !!

The vent -rite #35 is on the RETURN side not the supply side, sorry for the incorrect post.

BobC

Change and add vents first

Before I started to mess with the boiler piping I would replace that vent with 2ea Gorton #1's and i would find a way to add the same to the other main. That location is fine for the existing vent, you can add vents at the end of the other main or at any convenient spot on the return.



The vents HD sell are usually not very good, your better of with a Gorton or Maid O Mist vent. You can get a Maid O  Mist 5L that comes with 5 different orifices at Amazon for cheap money, that will let you easily change the venting rate.



Have you pulled the pressuretrol off the pigtail and checked to be sure it is clear? If the boiler were running at high pressure that makes everything worse. Ifg you do mess with the boiler piping you would be best off replacing the copper with threaded steel pipe and using both risers into a drop header would be as good as it gets for dry steam.



I would fix the venting and make sure the boiler is operating at low pressure before messing with the boiler piping. You might want to add alow pressure (0-3 PSI) gage to the pigtail along with the pressuretrol so you know what the pressure is; the 0-30 PSI gauge is not very usefull at the low end. Also if your seeing a lot of bounce in the gauge glass a good skimming is in order.



Bob

Frostman

Vents & new pigtail guage

Bob, I can very easily install a 2nd vent (Gorton's #2) to the other return. I have not pulle doff the pig tail but will do, and install a 0-3 psi guage @ the same time.

One questions is, ".. both risers into a drop header" , could you please either describe this or point me in the direction of a diagram of it.

If replacing the copper with 2" (is 3" required or better?) iron pipe, I'll do it, I prefer to do the right job once. Thanks for all your help on this.

FYI, it's a Weil/Mc-Clain EG-35 gas fired boiler and I only see 1 tappig on the top for he steam supply

Jamie Hall

That Weil-McClain does have

only one riser tapping; even larger ones may have only one.  But that doesn't prevent you from creating a drop header if you want to work on the boiler piping.  Up, over, down into one end of the header, then take your steam mains off the top of the header and, at the far end, your equaliser off the other end and down.

Frostman

drop header & vents

Thanks for the info. I've been aaway for a week.  I will intsall TWO vents on the return, piping ofr the new second one isnt a problem, I'll clean out the pigtail, I went to my plumbing supply ( not HD) looking for a 0-3 psi guage, the guy looked at me like I was stupid. Where can I get one, or please provide me with a name and I'll check amazon (that's where I'm getting the Gorton's #1's).

Regarding the drop header, where it drops down must also be above the 24" critical measurement, right ?  If you look at the pics , I have plenty of room to come up, then drop, I'm understanding that it is best to increase from 2" to 3" at the first elbow, and continue the 3" all through the drop header  right to the 2" equalizer.

Once again thtnk you all very much for your help. My friend & "Go To Guy" for steam has recently passed away and it's times like this that remind of it.

vaporvac

The higher the better...

Just another homeowner, but my understanding is the higher the better. This is working out great on my recent install. The price of straight pipe isn't much if you have the head room. I only increased the header part to give the steam and water more space to separate. Don't go down in size on the equalizer until you go vertical.

You might try Karen at simplyplumbing.com for the 1-3lb. gauge.

Sorry for your loss.

Colleen