System Balancing and Hofmann 1A versus Ventrite #1 vents

roc_rktec

I live in a smaller 1928 house with a poorly balanced single pipe steam system which short cycles. Last year during the cold of winter I did my homework and read "Greening Steam" and skimmed "The Lost Art of Steam Heating." I dutifully measured my three steam mains, associated risers, and nine radiators and calculated the volume of air in each. I have the following questions/problems:

1.) Two of the three steam mains only service two radiators each and do not have main line vents, should they have main line vents? The third main services the remaining five radiators and splits into two branches about 20 feet from the boiler. The branch that services 3 of the 5 radiators on this line has the only mainline vent in the system located as recommended in Dan's books (at the end just back from the return). Should the other branch of this mainline that services two radiators also have a mainline vent?

2.) I have what appears to be a mainline vent, located right off the boiler. Is this necessary? What purpose does it serve?

3.) Hoffman 1As seem to have been the standard for adjustable radiator vents, however I have seen that their quality and ease of use may not be all they're cracked up to be...and that Ventrite #1s might be a higher quality alternative. However, I am aware of the slower venting rate of Venrite #1s versus Hoffman 1As, and so I am left wondering is there a general rule on how fast I should be evacuating the air out of the system to avoid back pressure and short cycling of the boiler?

4.) If I were to maintain the existing design of only having the above mentioned mainline vent on the long branch of my third steam main...is it feasible that I could adjust for this imbalance at the radiators with Hoffman 1As or Ventrite #1s?

Please let me know what additional information or photos you all might need to more accurately respond.

Thanks!

-Chris

KC_Jones

You need vents on all the mains. Where there is air steam can not go. Trying to balance using only the rad vents is an exercise in futility. Think of it this way the first rad on the line will vent that air, but will also start filling with steam before the next rad finishes venting to even get steam. Once the next rad gets steam the first one is getting hot most likely very hot since you had to use such a large vent to vent the main line. So that room gets hotter and the next one is cooler or possibly doesn't heat at all because the thermostat kicks the boiler off before it even gets steam. ALL mains in the basement need vents and they need the appropriate amount of vents for the length and size of pipe. Since you say you already measured everything you can post here and we could recommend how much main venting you need. A rule of thumb is 1 Gorton #2 vent for each 20' of 2" (nominal, 2 3/8" OD) pipe. Without the main vents getting the system truly balanced is next to impossible.

Fred

I use the Hoffman 1A's on my radiators. They are very reliable but some people say they click when closing and they don't like that. I haven't experienced that, except on one vent. Not sure why. Maybe they changed to a different metal or thinner metal construction. Some feel the cap on the 1A's is a little sloppy and if you aren't careful when adjustion, it can partially cover the vent opening. I haven't found that to be an issue as long as you make sure the cap is centered when tightening the screw.
You say you have a main vent mear the boiler, is that on a dry return for one of the mains(or branches) that doesn't have a vent at the end of the main? If so, that location is fine but, as has been said, measure your mains and vent each one either at the end of the main or somewhere along the dry return, before it drops into a wet return, if you can find a convenient location.

roc_rktec

Alright...I hope that people are still able to see this thread and will comment...

The main lines are 2-1/4" OD iron, and the lengths are as follows

Main #1: 40'-0"
Main #1 branch: 14'-0" (after 26'-0" in common with Main #1)

Main #2: 23'-6"
Main #2 branch: 14'-0" (after 15"-6" in common with Main #2)

Main #3: 17'-0"
Main #3 branch: 16'-0" (after 10'-0" in common with Main #3)


Since Mains #2 and #3 only service two radiators each, would it make sense to install a main line vent near the branch to vent the pipe length shared in common between the two radiators, and then treat the branches as part of the "riser" to the individual radiators?

Another issue at hand is that installing new main line vent(s) will be difficult to accomplish for this heating season due to the tight confines for access and the existing asbestos insulation.

Fred, I believe you are right in that I have a vent on the dry return, although it looks to be in rough shape and would appreciate any advice on its replacement or necessity.

I have attached a photo of the boiler, the main #3 branch, and the confines I may have to deal with installing a main line vent.

roc_rktec

Also, if I am to attempt installing new mainline vents into an existing system without them...however much of pain in the **** am I creating for myself? What are the general steps for doing this? Drill and tap? Call a plumber?

ChrisJ

Has anyone seen @Steamhead ?

KC_Jones

Wow that piping...I have no words. Please tell me you bought the house like that and someone else paid for that horrible install. You can work on the venting, but honestly I think I would skip it and save the money to repipe the boiler. That thing is piped so beyond wrong I'm not even sure where to begin. The only thing I see correct is they used both tappings off the boiler after that it's all wrong. I would be willing to bet this is contributing to some of your issues. I'm not sure if I have seen someone post one that had the risers reduced down that small. Is that 1" or 1 1/2" copper?

Fred

Yes, it is piped really wrong. That is going to have to be corrected before I'd worry about venting. I'd have whoever corrects the near boiler piping add the vents at the appropriate places on the Mains. The one near the boiler is on what appears to be a drip leg, the riser from the boiler and what is suppose to be an equalizer. That vents nothing as it closes as soon as steam get there from the boiler.

roc_rktec

It is 1-1/2" copper. Does it make any sense to at the very least get some adjustable radiator vents to balance the system somewhat?

KC_Jones

roc_rktec said:

It is 1-1/2" copper. Does it make any sense to at the very least get some adjustable radiator vents to balance the system somewhat?

Perhaps, but if you ever plan on fixing the piping (I would depending on boiler age) you will probably have to re-balance it anyway. It's your house and your decision to make we can only offer our opinions. 1 1/2" is still massively undersized. Honestly the way it's piped I am not even sure if you could balance it even a close. One side is probably making dryer steam than the other although neither side could possibly have very dry steam at all. It's just a mess really. Do you know how old the boiler is?

Fred

You can't balance the radiators until the mains are properly vented but as has been said that piping has to be fixed. First things first. Trying to balance the radiators at this point is a waste of time and money.

roc_rktec

The boiler is a Utica Boiler and was installed in 1992. Atleast according to my calculations it was properly sized to meet the demand of the radiators. I will post the details of the boiler tonight when I get home.

Does anyone here know of a good boiler tech in Western New York? The main companies around here in Rochester, NY have proven themselves to be quite lacking in knowledge.

roc_rktec

Here is a quick diagram of the system. "L" is for lower, first floor, radiators. "U" is for upper, second floor, radiators. Perhaps this will help with the discussion of whether and where to put mainline vents...after fixing my biggest problem, the undersized risers from the boiler as described above.

roc_rktec

Fred said:

You can't balance the radiators until the mains are properly vented but as has been said that piping has to be fixed. First things first. Trying to balance the radiators at this point is a waste of time and money.

Fred, and/or others, what size piping copper or iron should be used for rebuilding the risers from the boiler?

Fred

Everything above the water line should be black iron piping. The boiler risers should be the same size as the boiler tappings (do not reduce them down). The Header should be one size larger and each main should tie into the header individually. That piping should be the same size as the mains. The way it should be plumbed is: Risers out of the boiler on one end of the header, Mains next and then the equalizer on the other end of the header. If you still have the owner's manual, look at the installation instructions to see how it should be plumbed. f you don't have a mainual, contact Utica or google it on the web and you will find a copy. Virtually all boilers are plumbed the same way (when done correctly) so you can look at some of the PRO installation on this site to visually see what you need to do.

hvacfreak2

ChrisJ said:

Has anyone seen @Steamhead ?

I spoke to him last Saturday night and he was working , I'll bet he is non stop right now.

KC_Jones

I think Chris made that comment, because he is constantly commenting about these brand boilers being piped wrong over and over again.

Dave0176

Here is how this boiler is supposed to be piped, and keep in mind our very own Steamhead has said time and time again, this boiler is very sensitive to piping, if your going to get any were near the possibility of having dry steam, you should follow the install manual to a TEE..........

And even then this boiler with it's side steam outlets and very narrow boiler sections, is very suspect to producing dry steam.

Dave0176

Were I live in Woodbridge NJ almost every house I've gone into with a steam boiler seems to have a Utica boiler, it's as if they gave them away for free or somthing, and EVERY single one is piped incorrectly, copper or steel.

roc_rktec

Yikes! Thanks for all of the comments everyone! Now if I were to attempt to redo the piping myself (next spring), what would it entail. Am I just dressing the threads and tightening sections together? How does one go about cutting threads on 2-1/2" iron pipe?

Also, does anyone have any comments about Hoffman 1A versus Ventrite #1 for adjustable radiator vents...aside from the differences in vent rates?

I have attached a photo of the information plate on the boiler.

roc_rktec

roc_rktec said:

Alright...I hope that people are still able to see this thread and will comment...

The main lines are 2-1/4" OD iron, and the lengths are as follows

Main #1: 40'-0"
Main #1 branch: 14'-0" (after 26'-0" in common with Main #1)

Main #2: 23'-6"
Main #2 branch: 14'-0" (after 15"-6" in common with Main #2)

Main #3: 17'-0"
Main #3 branch: 16'-0" (after 10'-0" in common with Main #3

After my near boiler piping problems are remedied, would anyone be able to comment on whether and where I would need mainline vents? See the attached diagram.

Mains #2 and #3 only feed two radiators each, so should I only be venting the main that is common to both radiators and treating the branches as part of the risers to the radiators?