Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Very close Net IBR steam Sq Ft

Bio Member Posts: 278
My rental units measurements calls for a new boiler with a Net IBR ratings 326 Sq Ft, boiler I'm thinking to replace the old boiler with a Burnham IN5 or a New Yorker CGS 50, both have Net IBR of 358 Sq Ft, will this cover me for those very NY cold days, Pipes are insulated, new double pane windows reolaced, please give me some advice as it looks like that it will not be oversize or undersize, would I be ok?


  • gerry gill
    gerry gill Member Posts: 3,032
    Sounds like a perfect fit

    to me..don't forget the manufacturer puts in a third extra boiler for piping and pick up..so if your sized even close on the under side it would still work..your on the over side just slightly..but it usually doesnt come as close as you have it..you should be fine.
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • Bio
    Bio Member Posts: 278
    Too good

    to be truth, that's why I had to ask, should I use both risers, manufacturer says is optional, also the fact that 3 radiators at 27 Sq ft radiation each are not in use because oversize for small bedrooms could help
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,564
    Close call

    Is this 1-pipe or 2?

    Have you checked the edr of the overheating radiators against the room heat-loss? The original installers were pretty good at choosing the right size for the room, and the overheating could be a symptom of some other factor in the system, such as over-pressuure, thermostat location, bad main venting, etc.--NBC
  • Bio
    Bio Member Posts: 278
    1 pipe

    Thanks Gery and NBC for answering,

    1 pipe steam system, these are 3 bedrooms that are 9'x10' 8'high with 3 year old double pane windows, tenants asked me to close the radiators because its too hot and they feel if they leave the door open is enough heat for the rooms they say, I will check the main vents or is possible radiator vent needs to be check, I'm planning to balance all radiators and mains vents, I wanted to be sure if the closeness of the IBR steam Sq Ft will short change me in the very very cold days, I guess my question to you the pros is has this been seen and worked with no problem,
  • Rod
    Rod Posts: 2,067
    Use TRVs

    Hi- If you getting overheating, use a TRV on the overheating radiators.  On a one pipe system there is a special model TRV that is installed between the Radiator and the radiator vent. (see attached brochure below)  I use TRVs on my radiators so I can shut down some of the rooms in my home to minimal (above freezing - 45 F) settings and also so the bedrooms are cooler in the evening.  This saves fuel.

    - Rod 
  • ChrisJ
    ChrisJ Member Posts: 12,836
    edited May 2012

    I'm a homeowner NOT a pro.

    The boiler I installed in my own home last fall is almost an exact match.  Its a WM EG-45 rated for 392sqft and I have what comes to 392 sqft of radiation if I include four uninsulated pipes going between the 1st and 2nd floor.  This is a single pipe system.  The system can heat every radiator all the way across though it takes time which is a good thing.

     My system at first had balancing problems, I had two radiators which refused to heat most of the time.  I had to insulate my mains and reduce venting on my radiators slightly but after tweaking over a period of a month or two I ended up with a beautiful system.  I'm using many Gorton #2 main vents and all Hoffman 1As on my radiators and the system is near silent.

    By the way, a WM EG-40 is rated for 325sqft of radiation and has two 3 inch tappings.  I spent quite a long time looking at different boilers, I originally wanted to go with Burnham but my overall opinion is all of the major brands are the same overall.  I decided to go with the WM EG series because I could get it locally and they had the size I needed.  If you consider going with something like the EG-40 which is an exact match, make sure your numbers are accurate. 
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Bio
    Bio Member Posts: 278
    Close IBR

    Thanks for the response ChrisJ, matching IBR in paper looks good, that's whats recommended by the pros, some reassurance from the pros and homeowners are always good, I will pursue what you have done, how many main vents did you use?
  • ChrisJ
    ChrisJ Member Posts: 12,836
    Main vents

    Main venting depends on your mains.

    I have a 29' 2" main and a 11' 2" main. I used 3 Gorton #1s on the 29' main and ended up sticking a Hoffman 4A on the 11' to balance it. Originally that short main, being first in line was stealing steam, the 4A vent solved that problem.

    I'm probably going to go to four Gorton #1s on the long main and switch the 4A to a Gorton #1 and see what happens. I didn't realize it was building any pressure until I was adding a gas line for my outside grill and heard the boiler fire up and built pressure. I was amazed at how much air rushed through those vents for a minute or so and others say, if you hear the vent its probably restricting flow.

    If you let us know how long the mains are and the size we can give recommendations.

    Here is a picture of how I installed the vents. I have yet to finish insulating that part of the main.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Bio
    Bio Member Posts: 278

    I will get that info tomorrow, what I know is that there are two mains, one for each Apt, both mains run around the basement and returns to the boiler, vents at the end and finishes at the hartford loop, each main have a single vent
  • Bio
    Bio Member Posts: 278

    Its two ( one for each apt) 90' piping wrapping around the basement with one vent on each return the drops to the hartford loop
  • ChrisJ
    ChrisJ Member Posts: 12,836

    If each main is 90 feet of 2 inch pipe I would say no less than two Gorton #2 vents per main.


    If you want to learn how to size vents better take a look at the Balancing steam chart at :


    That not only explains how to figure out what venting you need on your radiators and mains, it even gives vent rates for all of the common vents. I'd be lost without it.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Bio
    Bio Member Posts: 278
    Thanks everybody!!

    I know for sure I'm on the right track and will be able to start with some confidence, you guys provided a lot of friendly information
This discussion has been closed.