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    Where do the vents on the mains go? (18 Posts)

  • HoyteKing HoyteKing @ 9:56 AM
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    Where do the vents on the mains go?

    Our condo has a Well-McCain boiler that needs venting on the mains. We recieved an excellent report from one of the best steam persons in the country with a diagram. The position of enough condo owners is that I "influenced the contractor" and so the evaluation has been rejected.

    The diagram from the eval is attached. The boiler manual is attached, also.

    We have had two vendors in that "have 30 years experience with steam" and don't like evals "with info that someone got off the internet."

    The proposal is to clean the traps and resize the vents off the mains. There are three runs. All runs are to be vented. That is at varience with the eval right there. Location is a problem, too. I don't believe that where the vents are now is a good spot, but am just a layman.

    One steam guy said the install is not that important. If we change it, not much difference. He did admit the boiler pipes are part of the boiler design in modern boilers, though. If the pipes don't knock, why worry, was his conclusion.

    Question - Where do the vents go?

    Video on YouTube of the boiler:
  • FJL FJL @ 10:11 AM
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    As a NYC Co-op Owner . . .

    I feel for you.  Good luck.
  • Rod Rod @ 1:59 PM
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    Main Vents

    Hi- i guess the first question that comes to mind is what problems are you having with the system at this time?   The other questions I have, is this a one or two pipe steam system and what is the model size of the boiler?  While the videos are good, it is better to have photos of the piping taken from farther back as we can then take time to study the piping and trace where the individual pipes lead.  Looking at the videos it would appear that the venting capacity we can see is extremely undersized considering that this may be a fairly large building (We don't know the building size or the connected EDR)
    In the drawing what is the significance of the figures and position of the Items marked "A" & "B" ?   As you have already determined the boiler isn't piped correctly. As for main vent positioning  I'm a bit concerned about resolving the locations of traps before deciding where the vents should be located. If the present vents are operating okay it maybe that you would just want to increase the venting capacity at the present location for a start.
    - Rod
    Edit:  When i looked over your videos a lot of things seemed pretty "weird" so my reply was basically intended to get more info on your system.  Since I posted, Terry, who is a very experienced steam pro , and Dave, who while he says he isn't a pro, has a lot of steam experience, have replied and both have addressed specific items. If it were me, I would place great value in any recommendations they may make. 
    This post was edited by an admin on February 24, 2012 2:43 PM.
  • HoyteKing HoyteKing @ 5:19 PM
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    eval on our system

    It seems I am unable to attach the eval. Well, basically it covers absolutely everything one would wonder about, including: lack of insulation in parts of the piping, piping the wrong size, bad install, no venting, etc.

    Recommendations discuss what to do in what order. Vent the mains and insulation are up front.

    The only thing not covered is how many vents in the two spots needed. The new people think this eval is worthless, and say so. They cannot give any logic beyond the typical standard lines for laymen like me and my neighbors. It sucks.

    Here is an edited version of the eval we recieved last April. Just to be clear, this has been read by a great steam person who said it was great. It was written by one of the best steam persons in the field, according to many. I have found the logic there to be sound as much as I can understand it (I read the Holohan books).

    The only thing that wasn't there was about where to put the vents on the mains, and how many on each.. I get different answers from different persons. Why the heck is that? They all agree that the mains need to be vented, but where?

    I personally go with this eval and the accompanying diagram. But I am not able to make that decision alone.
    This post was edited by an admin on February 24, 2012 6:05 PM.
  • Rod Rod @ 7:54 PM
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    File Upload to the Wall

    You can only upload two types of files - either images (JPG) or PDF files.
  • HoyteKing HoyteKing @ 8:04 PM
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    The eval

    1. The
      piping system appears to be in good condition and is a configuration that
      tends to be very long lived with little maintenance required when left in
      its original state.  There are few
      areas where heavy corrosion can occur. 
      Just as a precaution, it may be advisable to check all the piping
      mains to be sure they are constantly sloping toward the end of the
      main.  The piping needs to slope to
      the end of the main to ensure that all water drains from the piping at the
      end of each heating cycle. If water lies in the piping after the cycle it
      can cause corrosion of the piping.
    2. The
      system has seriously inadequate venting for the steam mains.  This is typical for a system that has
      not been converted from coal use to oil or gas.  Like the radiator vents that vent air
      from the radiators, main vents are needed to vent air from the steam
      mains.  These large diameter and
      long pipes hold large amount of air that needs to be vented very quickly
      when the boiler first starts making steam. 
      Getting the air out quickly allows the steam to travel completely
      through the system at very high speed (up to about 25 mph), reaching all
      the supply pipes leading to the radiators at about the same time.  Since the steam arrives at all the
      radiators at about the same time, heating of the radiators starts
      throughout the building about the same time.  This eliminates the chief cause of over
      and under heating.   Using only
      adjustable vents to attempt to balance the system is poor practice, as
      radiator vents are not designed to quickly vent the large amount of air in
      steam mains.
    3. While
      the majority of the steam piping in the basement still retains its
      insulation, there are some long sections where it needs to be
      reinstalled.  Steam systems are
      designed to have insulated piping and if it is not, heating balance can
      suffer because the uninsulated piping robs heat that is intended for the
      radiators and also slow downs the heat up time for the steam main, causing
      further imbalance.  In addition,
      heat is wasted heating areas to higher temperatures that are not living
      space, increasing fuel bills.  This
      waste is especially present in the boiler room area, since this very warm
      air is used for combustion and exhausted out the chimney.  With proper insulation, many boiler
      rooms I have been in stayed at about 70F in the middle of the winter.  The amount of heat wasted by this
      uninsulated piping could easily heat another unit.


    Boiler/ Near Boiler Piping


    1. The
      boiler appears to be well equipped with piping and valves to ease proper
      regular maintenance of the boiler. 
      Drain, skimming and flushing valves are all in place.
    2. The
      water level operating control is not piped according to manufacturer’s
      instructions and this can potentially be problematic.  This control senses the water level in
      the boiler.  As water is boiled off
      as steam the water level drops. 
      When the water level gets low enough a pump on the adjacent storage
      tank is turned on to pump additional water back into the boiler to raise
      the water level.  If the pump was to
      fail and the water level continues to drop, the control shuts down the
      boiler.  The problem with the piping
      is the upper connection has been tied into one of the boiler risers.
      Steam/ water are moving very rapidly through these risers.  When steam/water moves at high velocity,
      low pressure is created.  This low
      pressure is just like that above an airplane wing which causes the plane
      to lift off the ground.  The upper
      connection is tied into piping where the pressure is dropped, so it can
      draw the water level up in the control, giving it a false reading.  It is difficult to say how much the
      water level is affected. Fortunately, though, the velocity in the riser is
      lower than typical due to how this particular boiler is installed.  There is also a backup water level
      control that is piped correctly that can shut down the boiler if the first
      control is not operating properly, so there is less of a safety concern
      due to the boiler running out of water and causing an explosion or fire.
    3. The
      risers coming out of the boiler are not tall enough.  They do not meet the boiler
      manufacturer’s minimum requirements.  
      This requirement is virtually a universal requirement for all
      modern steam boilers and is not dependent on the boiler design. This
      minimum piping height is required because when the boiler boils the water,
      a very large amount of water and steam rise up into the piping.  This water/ steam mixture rises about 24
      inches above the boiler water line and the piping needs to rise above this
      point to help prevent large quantities of water from leaving the boiler
      with the steam.  Providing this
      additional riser height would have only required 2 additional elbows being
      installed allowing a more effective header configuration to be used as
      part of the installation.
    4. Fortunately,
      the installer used two large pipes coming out of the boiler (risers), so
      this can help reduce the amount of water that gets drawn out of the
      boiler.  The reduced velocity of the
      steam rushing up and out can help the water stay in the boiler.
    5. In
      addition, an oversized header was used. 
      A header is the larger horizontal pipe that the risers attach
      to.  This horizontal pipe allows the
      water and steam mixture that exits the boiler to separate.  Gravity pulls the heavier water to the
      bottom of the pipe, and the lighter steam rises to go out into the
      system.  The larger and longer this
      pipe is before the connections to the system are made, the more effective
      the separation occurs.  Water that
      gets carried with the steam into the system piping will slow down and cool
      the steam, causing uneven heating and more corrosion of the system.  The purer the steam is that enters the
      system, the more efficiently the system will run, providing improved
      comfort and lower fuel usage.
    6. Unfortunately,
      the header is completely missing the drain pipe required to drain the
      separated water out of the header. 
      Once again, the need for this drain piping is universal for all
      modern steam heating boilers.  It is
      likely that instead of this water draining back into the boiler, it is
      being carried out with the steam into the system.
    7. Judging
      by the piping in the boiler room, when the new boiler was installed, the
      traps, strainers, and condensate tank and pump were installed.   With this equipment working together it
      allows the returning water from the system (condensed steam) to collect in
      the tank, and a pump is used to return it to the boiler.   Typically none of this expensive
      equipment is required for peak performance of your type of steam system,
      even with a modern boiler.    The
      original piping allowed the water to drain by gravity directly into the
      boiler.  No assistance of a pump was
      required.  Many installers also
      claim that this equipment is required because new boilers are so small and
      the water level will need to be too high in the boiler to make up for the
      boiler’s small size.  The additional
      tank is then required to store extra water for the boiler to use, while
      keeping the boiler water level low enough for proper operation.   This is also very rarely the case with
      a properly functioning system, especially for your type of system.  This equipment probably serves no
      purpose and only increased the overall cost of the boiler installation and
      will increase maintenance and service costs.  When repairs are required of this
      equipment, I recommend that it all be removed and the system restored back
      to its original simple and more efficient piping arrangement of directly
      returning the water from the system into the boiler.
    8. The air vents at the end of the steam
      mains serve absolutely no purpose. 
      The large blue Y-strainers located just above the condensate tank
      also have no purpose, even if retaining the condensate tank and pump.
    9. The
      steam traps are not installed correctly. 
      Steam traps allow water and air to pass through, but stop
      steam.  When the steam system first
      starts, there is very little pressure on the steam side of the trap;
      however, a considerable amount of water is generated when the steam
      condenses on the cold piping.  This
      water needs a certain amount of pressure to flow through the small
      passages in the trap. The minimum pressure rating of traps is ¼ psi or 4
      ounces pressure to allow a fixed amount of water to flow.  When the system is starting up, the
      pressure is nearly zero, but a large mount of water needs to flow through
      the trap.  The proper way to install
      these traps is to install a vertical pipe down to the trap inlet so water
      can build up in the pipe and create enough pressure for water to pass
      through.   Typically the current
      installation will cause banging in the steam main, but I did not notice
      any banging when I started the system. 
      I suspect that the inadequate venting is allowing pressure to build
      in the system quickly enough to push water through.  The water also arrives at the traps with
      considerable delay due to the inadequate venting, allowing pressure to
      build before it arrives.  Once these
      problems are corrected the traps will need to be repiped.  Since none of this equipment is needed
      anyway, I’d suggest just eliminating it and repiping the system as it was
    10. Judging
      by the size of your building and how the system performed when I ran the
      boiler, it is likely that the boiler is larger than necessary to heat your
      structure evenly and efficiently. 
      Too large a boiler increases installation costs, increases cycling
      wear on the operating components and heat exchanger, causes air vents to
      fail early, leads to higher ongoing repairs costs, decreases efficiency
      and can contribute to imbalanced heating. 
      Fortunately it is a design were it is likely that the size of the
      flame can be reduced to a more appropriate heating output, eliminating or
      greatly reducing most of these problems and potentially improving the
      boiler efficiency.
    11. The
      burner/boiler may be able to be converted to modulating input, which could
      work well with the addition of Thermostatic Radiator Valve in the
    12. The
      addition of a modern control system would be a good investment, once a
      plan is decided on how to deal with the system itself.  Which control to use would depend on the
      decisions about how the heating system will be used. An outdoor shutdown
      thermostat could be installed in the meantime to help prevent overheating
      in warmer weather.



    Other items:


    1. The
      gas main is undersized due to the length, diameter, and size of the
      equipment. This may cause the water heater and boiler to operate less than
      optimally, especially in very cold weather.  In very cold weather, pressure often
      drops in gas mains in the street, so undersized lines in your building may
      have more impact. 
    2. All of
      the hot water lines should be insulated. 
      This is a year round waste and causes the air conditioning to run
      more in the summer.



    Recommended improvements, in order of likely cost
    effectiveness and importance to safety and longevity:


    1)    Correct
    the piping for the water level control.

    2)    Install
    proper main venting for the system (see attachments)

    3)    Insulate
    all exposed steam piping.

    4)    If
    steam traps create banging in system, repipe them or eliminate them along with
    the condensate tank and pump and rework the boiler controls for using a
    conventional electronic water feeder.

    5)    Insulate
    all exposed hot water piping.

    6)    Eliminate
    separate metering

    7)    Check
    the necessary capacity of the boiler and reduce capacity as possible.  This would be completed along with tuning the
    boiler (this should be coordinated with 5 as adding additional gas loads to the
    meter may require a bigger (more expensive) meter if the boiler capacity is not

    8)    Install
    drain in header (this is a higher priority if the boiler capacity remains as it
    is now).

    9)    Check
    for problems with the radiators above Ron’s storage locker.

    10) Install proper
    height risers on the boiler. (This should probably be completed with 8 since
    both require welding).

    11) Provide
    combustion air.

    12) Reroute gas line
    to boiler to shorten the piping if the reduced boiler capacity does not require
    a larger gas line.


    At this point you will have the fundamentals in very good
    condition.  After 1, 2 and 3 are
    complete; you can begin evaluating heating balance and see where problems may
    still exist. Also, at this time it may be good to discuss whether there is the
    desire and/ finance to begin upgrading the complete system to use Thermostatic
    radiator valves (TRV’s) on all radiators to provide room by room control or if
    the preference is to keep the system essential under one control.  TRV’s could also be used to address randomly
    occurring overheating issues due to solar gains, cooking, etc.  They can be used judiciously in this way
    along with balancing the system using variety. 
    Another potential method is to use them only on the large radiators in
    each unit (typically living room and dining room) to provide much greater
    individual control at reduced expense. 
    Any reductions in overheating that these TRV’s can provide will help pay
    for the controls in fuel savings and improve comfort.

                The above
    choices will need to be integrated into the choice of control to use.

  • Dave in QCA Dave in QCA @ 10:21 AM
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    Excellent Evaluation

    This evaluation appears to be very complete and accurate.  The person doing the evaluation spotted every issue that I could see in your videos plus a miriad of things that could not be seen.  I imagine that this evaluation is of concern to the ruling body of the condo.  It would make me concerned if I thought everything was OK, but than received this!  How could so many things be wrong? 

    You are fortunate to have gotten this evaluation.  Even if there is resistance to accept it, it will be helpful over the long haul.

    BTW, google the address and the building is beautiful!  Great neighborhood too!  One of my favorite parts of town.

    One question, what was the item referring to separate meters referring to?
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
  • HoyteKing HoyteKing @ 11:09 AM
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    gas meters

    Every meter must be "rented" individually from the gas company here in Chicago. If a condo association has one meter, we are collectively saving around $15 per unit every month minus one meter. This adds up to quite a bit of savings over time. The person doing the eval let us know about this, and has saved others mucho mula.
  • Dave in QCA Dave in QCA @ 2:07 PM
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    Oh Of Course!

    Yes, I see. The occupants are all owners and everyone is paying that monthly service fee on the gas service for their kitchen. 
    I have the same issue with my building, except that my tenants are not owners.  However, there is a cost of $10 / month for each of them.  That is our local utility service fee.  Most gas bills will show no gas usage during the month.  Occaisionally, 1 or 2 cf.   I have considered have the meters removed and combining the service as It makes the apartments a better value. 
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
  • Rod Rod @ 2:42 PM
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    Steam Pro

    If you live in Chicago you have really lucked out as there is an excellant steam pro located there. His name is Dave Bunnell,  email:  Phone 1-877-567-7070
    His knowledge of steam systems will easily run circles around most other so called "steam pros".  I've posted a picture below of an installation done by Dave Bunnell. It shows the quality of his work and his ingenuity in designing a modern steam system upgrade. If I was in a condo association I would want a system like this . Note the two boilers.  To save fuel only one is used during the light heating load periods in the spring and fall. The second boiler comes on line when it gets very cold and the heating demands are much higher. Staging two boilers this way saves fuel and should one of the boilers malfunction, you always have heat!
          It would seem to me that your condo association faces two scenarios, the first being fixing the present system so that it provides comfortable heating and efficiently and the second planning for a long term replacement of the present system and what you need is a steam pro that can help you accomplish both. You're lucky that you have a good steam pro available. There isn't such a thing here in rural Maine where I live.
    - Rod
  • HoyteKing HoyteKing @ 3:02 PM
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    steam pro in chicago

    Yes, I know about BoilerPro and am advocating for this company to work on our building. The "veterans" don't seem to like people like Dave, though. They see what people like him have to say as "something you could get off the internet" or "exageration" of things that are not that important.
    Try finding someone else in the Chicago area like him. I have not found it to be possible so far.
  • Dave in QCA Dave in QCA @ 3:44 PM
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    They are entitled to....

    The folks in your building are entitled to their own opionions, but not to their own facts.  Of course, as I said in another post, it may be very difficult for them to come to the realization that the contractor or contractors that they have had faith in have let them down.
    1) Your present system is working great!  is that correct? 

    Uh No.  It's not.  and, why might that be?

    2)  In the basic installation of the boiler, every part of the close boiler piping fails to meet the manufacturers minimum requirements.  Also appears to no meet all basic codes that require a header, equalizer, and a hartford loop.  It amazes me that it ever passed city inspections.  Especially when it comes to light that there is no supply of combustion air.

    It appears that the rest of the folks in the building can continue with the existing contractor who will tell them that everything is fine, or they probably could find another contract that will also say everything is fine.  But, that is not going to fix the problems that are fundamentally wrong with the system and no doubt causing imbalance and expensive operating costs. 
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
  • HoyteKing HoyteKing @ 4:20 PM
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    Ahhhh, the city inspection!

    That is where we are right now. Everyone in our association is thinking about whether or not they want a city inspection.
    About Chicago and city inspections. As I understand it, there are six inspectors left in the city. They barely have time to take care of the hospital and school boilers, let alone some rinky-dink condo building. All the other inspectors have retired. A great way to save money for the city. Why the developers in Chicago are not up in arms is a mystery to me.
    So, the monster "boiler company" comes in and does our install and is authorized to "self-certify" their work, kind of like our modern financial system. It works great!
  • Steamhead Steamhead @ 3:49 PM
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    I'll second that recommendation

    Boilerpro is one of the best. 
    "Reducing our country's energy consumption, one system at a time"

    Steam, Vapor & Hot-Water Heating Specialists

    Oil & Gas Burner Service

    Baltimore, MD (USA) and consulting anywhere.
  • HoyteKing HoyteKing @ 7:45 PM
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    one pipe system

    This is a one pipe system. The second floor is too hot, the third and first cool. About 30 vari-vents have been installed. Before they were installed, the third floor was horribly hot after installing insulation the summer before last on the roof.

    The vari-vents provide some venting, but have not made things better on the second floor. It is worst above the boiler, less the further away you go, but still unacceptable for all three third floor units.

    There are no present vents to work improperly. There is one little one in the basement furthest away from the boiler. It is a vent made for a radiator.
  • ttekushan ttekushan @ 2:13 PM
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    Vents may not do anything.

    The vents in question are part of a classic arrangement where they are perched atop a line that drops into a wet return (i.e., immersed in water below the water line of the boiler).    BUT you now have a vented receiver, i.e,, a boiler feed system and that tank is now the system vent.   Those vents provide no useful purpose anymore if this is the case.

    From the videos, it appears that the ends of the mains are now reduced and trapped with bucket traps.   Bucket traps are very poor at venting, though they are very reliable and low maintenance.  Those strainers MUST be kept clean. 

    IF there are traps ahead of those Tees with the vents on top AND the Tees with the vents drop directly into the short line leading to the vented condensate tank/boiler feed system, then those vents are no longer functional, being obviated by the conversion to a boiler feed system. 

    AND if those bucket traps in the video are responsible for venting the mains, then heat distribution will be delayed at radiators towards the end of the main.  Some rooms closer to the beginning of the main will bake while others near the end of the main will remain cool.   Is this happening?*

    ["closer to the beginning of the main" does not necessarily mean "closer to the boiler room" because of how many systems are piped.]

    And what's up with the aquastat? Hasn't anyone installed a proper boiler control, such as the  Tekmar 279 or a Heat Timer?

    Just some thoughts to consider.

    * Warning:  Facts and observations considered here are subject to nullification by virtue of having passed through the digital domain and accessed via the internet.  ;-)
  • HoyteKing HoyteKing @ 5:08 PM
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  • Dave in QCA Dave in QCA @ 2:19 PM
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    What are the symptoms?

    Your videos are good an allow us to see a number of issues with the system.  But, many systems are not installed correctly according to the manual, and seem to work fine.  Other systems will have no end of problems unless everything is precisely correct.  So, what symptoms or problems are you having with the system.?

    Regarding venting, The location of the existing 3 vents serves no purpose.  The piping proceeds to the boiler feed tank which is vented to the atmosphere, provided all of the venting necessary for the piping downstream of the traps.  You commented that the white PVC air gap was supposed to vent, but was not.  HUH?  It better be!  The tank has to be vented to the atmosphere.  It is likely that you cannot feel air coming out, but unless someone plugged it up somehow, it is venting.  If it is plugged, it needs to be corrected immediately.

    The venting of your mains presently is occurring through the inverted bucket traps.  Whatever the venting ability of those traps are, that is what you got.  Additional vents downstream of the traps, including the 3 that are already there will have no effect whatsoever. That piping is already open to the atmosphere through the boiler feed tank.   If additional venting of the mains is necessary, it must be upstream of the traps. 

    You indicate that the traps are going to be cleaned.  It is important to make sure that they also clean the y strainers, both the ones located upstream of the traps and the ones upstream of the tank. 

    Other issues that I see....
    The header (if there is one) is not 24" above the water line.  That is a minimum.  It does not appear that there is clearance between the boiler and the basement ceiling for this to be piped correctly.  The model 88 boiler has a water line that is 49" above the floor.  They could have installed a model 80, which has a water line that is 36" above the floor, 13" lower than the boiler you have and would have allowed for risers of the minimum specified height, or more.   But, there isn't much that can be done about it now. 

    The Header... it appears that the boiler risers (those little short things that do not meet the manufacturer's minimum specification) turn into a header of sorts.  It turns and proceeds a fair distance before a main rises out of the top and proceeds on.  What we can't see is what happens at the end of that long header.  Is there an equalizer that drops out of the bottom and goes back to the boiler?  If not from this end of the header, perhaps from the other?  Anyway, that is a required part of the piping, and equalizer.  A Hartford loop is sometimes omitted an a boiler feed pump system, but that long header really need an equalizer leg coming out of it so that water is allowed to properly separate from the steam and return to the boiler.

    Also, the laterals located right after the risers are required by the manufacturer to be long enough to reduce expansion stress on the boiler.  They appear to be pretty short.  Additionally, good piping practice for cast iron boilers calls for threaded pipe joints on the risers and riser laterals to further assist in relieving expansion stress.

    If you had this installation inspected by the manufacturer with the question of whether the installation met their minimum requirements, you would get a resounding NO for an answer.   So regardless of how many years they have been in business, they may have a track record of inadequate installations. 

    What should be done?  Well, it would be a good idea for the condo or coop association to have an adequate replacement fund on hand because the boiler will likely not last as long as might if it were installed correctly.  Is it possible to correct the errors now?  Probably not.  There is not enough room in the basement to get a proper header with that boiler.

    If you are having problems with uneven heating and parts of the building getting steam much slower than others, then improved venting on the mains will probably help.  Especially on the main that is the longest.  Any additional vents should be installed upstream of the traps, or otherwise they will have not effect at all.

    The biggest issue that I see in the whole picture is all of the uninsulated steam mains.  They will cause a big loss of heat to the basement, causing unnecessarily high operating costs.  Also, they cause a lot of condensation inside the steam mains and further interfere with good steam distribution.  That could and should corrected now. 

    It sounds like your board has faith in the current contractor.  They don't know what they don't know.  And, its a difficult process for a person to lose faith in that which they have trusted. 

    As for the reliability of information found on the interenet.  That is a valid concern in the general sense.  I have seen several other help forums on line, and have seen some pretty poor advice being given on some of them.  I was skeptical when I first found this site.  But after reading for a short time, I discovered that there are a number of highly informed and highly qualified professionals contributing on here.  Additionally, there is a long list of well informed and very helpful "wallies".

    No, I am not a pro in the trades, but I do have over 20 years experience in operating institutional and process type steam plants.  I have learend that low pressure residential steam is a totally different animal and a different set of rules apply. 

    Wait to see if some of the pros weigh in on this thread.  Their comments will be the most accurate advice that is available in the USA.   Good luck!

    ps, as I was typing, I see that a few others have posted as well.  I'll have to run and read them and see if we are all seeing the same issues.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
    This post was edited by an admin on February 24, 2012 2:20 PM.
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