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Thermometer Heating Survey in my Coop Buildings

Hi all,

I live in Coop with two pre-war 4 story buildings. The first building has eight 1- to 2-bedroom apartments per floor and the second building has four larger units per floor. Both buildings are similar in steam riser layout but have slightly different layouts due to the larger apartments in the latter.

For years many people complain in the winter that they are either too hot or too cold. Since the comments are subjective and sparse I havent been able to make much sense of it other than (and what would be intuitive) folks closest to the boiler are too hot and people higher up and on the corner units too cold.

We have a 1-pipe steam system where the steam enters the risers from the bottom up.

Based on the situation I've put together the following approach to better understand the issue:

We will be deploying thermometers later this week at key locations throughout which record the maximum and minimum temperature over a 24-hour period (see attachment

1). Since all thermometers log max/min temperatures during the same 24-hour period we will be able to compare the data to see which zones are getting the most/least heat.

People would be asked to turn all of their radiators on during the study and place the thermometer in selected locations (e.g. middle of a room) and at roughly the same height off the ground for consistency (e.g. on a chair). 24-hours later we will ask all the participants to submit information such as recorded maximum and minimum temperatures along with some general info about their apartments (e.g. their radiator sizes (or volume of metal), notes if any radiators disconnected/not functioning/bad valves, known drafts, etc.)

We are going to use 4 thermometer locations per floor in each building at the same 4 locations on every floor and in both buildings.

I also put together the attached google form to collect the data when the survey is complete.

So, I am a civil engineer so this is out of my area of expertise but I would love to help make some people more comfortable and save money for the coop. I view this as a first step in getting some data that we can work off of.

I wanted to see if any of the experts out there would take a look at this plan and the attached post survey form below and offer any advise.

<a href="http://www.ebay.com/itm/Dual-Display-Electronic-Thermometer-Memory-Min-Max-History-Values-Reliability-/200916486773?ssPageName=ADME:X:RTQ:US:1123">http://www.ebay.com/itm/Dual-Display-Electronic-Thermometer-Memory-Min-Max-History-Values-Reliability-/200916486773?ssPageName=ADME:X:RTQ:US:1123</a>

Any constructive feedback would be very much appreciated!




  • Jamie Hall
    Jamie Hall Member Posts: 22,916
    Please shift this thread

    to steam heat if you can -- you'll get much more response!

    But it looks as though you are starting in the right place -- that is, finding out what is really happening rather than depending on subjective comments.  That will help.

    Once that is done, though, there is more.  You say this is one pipe steam.  It's not uncommon for it to be poorly balanced when it hasn't been properly taken care of over the years -- but it is usually not all that much of a hassle to get it much much better.

    Do you have access to the heating system?  I hope?  If so, find out what pressure it is operating at -- 2 psi should be the maximum.  Can you make a sketch or at least a written description of the where the steam mains go?  Are there any vents on the steam mains themselves, or on the risers?  or just on the radiators?  Are the steam mains insulated?

    And we will have more questions -- but do see if you can shift this thread to "steam heat"
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • refields
    refields Member Posts: 45
    Steam heat

    Hi Jamie,

    Thanks for the suggestion I believe the post was moved to the correct location.

    I can get access to the boiler room if needed, but am not the person responsible for controlling its operation. The URL for the Tekmar controller we use is below:


    I don't believe the controller has a direct pressure setting, but bases the heating cycle (on/off time ratio) off of the programmable settings and, the outside temperature and condensate return.

    There are vents at the ends of the steam mains and on top of the risers that I checked. The steam mains and risers are not insulated.

    I will get access to the areas of the basement and apartments required to make a plan view sketch of the boilers mains and risers and get back to you.


  • 1-pipe system survey

    I am assuming that this building was built as it now stands, with its original system. If that is so, then the radiators were probably correctly sized for the room in which they are located.

    To start with, verify that all radiators on a floor receive steam at the same time. Identical pats of butter on plates should all melt at the same time.

    Radiators which are slow to get steam are probably on a line whose main venting needs more capacity. A 0-3 psi gauge will show the back-pressure of venting which should be 2 ounces or so as the air starts to escape. If the pressure is over 2 psi, then the differences in steam arrival time due to venting problems will become more pronounced. It is best to start with slow Hoffman radiator vents for this, and later some changes can be made to speed up any laggards later.

    Once you have all the metal heating up as quickly as possible, then you can address the control system , and interior temperatures. Are there separate boilers in each building, or one? --NBC
  • ChicagoCooperator
    ChicagoCooperator Member Posts: 352
    He probably wants to check the radiators

    Since it's an owner occupied building, shareholders may have replaced radiators for a variety of reasons, depending on how the building was managed. Words of warning from someone dealing with the aftereffects of lax, laissez-faire, lackadaisical heating system management (i.e. too cold? Well, put in a bigger radiator...). I'd also do a survey of radiators to make sure that they are original or appropriate replacements.  
  • refields
    refields Member Posts: 45

    I know that people have in fact changed radiators over the years. Unfortunately, its not feasible for me to go around to each apartment and do a full radiator survey of both buildings.

    Do you think it would be useful to ask each owner to quantify their own radiator sizes in the room we are doing they max temperature surveys?

    For example, I can ask everyone to send me the length, width and height of the radiator(s) in the room and I can compare the volume of metal with temperatures.


  • vaporvac
    vaporvac Member Posts: 1,520

    Perhaps they could send you pics as well TO MAKE SURE THEY'RE IDENTIFYING THEM CORRECTLY. Sorry for the caps!
    Two-pipe Trane vaporvacuum system; 1466 edr
    Twinned, staged Slantfin TR50s piped into 4" header with Riello G400 burners; 240K lead, 200K lag Btus. Controlled by Taco Relay and Honeywell RTH6580WF
  • refields
    refields Member Posts: 45
    Floor Plans and Temperature survey

    Hi All,

    Attached are approximate floor plans for both buildings. The building on the second page is located to the right of the first building and on the corner of the block. Both buildings are 4 stories high and include a basement. There is one boiler plant for both buildings which is located in the basement.

    This evening I distributed thermometers to all of the owners with instructions to run the 24-hour survey tomorrow evening (Monday 3/3) until Tuesday evening.

    The purpose of this test is not to tune / alter boiler settings but rather to measure the relative heating throughout the buildings. The system was originally designed about 100 years ago, and it is my assumption that the the pipes, radiators and vents should have been sized with the goal of creating the same temperature in each apartment at about the same time.

    Since that time, the system has aged and apartment layouts, radiators and other components may have been altered, changing heat distribution throughout the buildings. Therefore, the purpose of this survey is to gather data to identify some potential problems and generate some ideas to help equalize the heat distribution.

    I look forward to sharing the results over the next week and hope to receive feedback from the heating community!
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    Posting pictures

    Show us some pictures of the boiler, and it's piping as well as the radiators. This sounds like the usual system imbalance, complicated by the probable extra distance the steam may have to travel to the farthest radiator in the non-boiler building.

    The pressure control would be on the boiler, and not part of the Tekmar controller. It's function is similar to the governor on an industrial engine, limiting in this case the maximum pressure which can be attained by the boiler. In my 55 rad system, the limit is 12 ounces using a vaporstat. If regular maintenance has been spotty, this control can plug up, and the resulting over-pressure travels more slowly through the pipes, costs extra money for fuel, and causes discomfort and imbalance. Lower pressures require maximum main venting, and it is not enough to think because the vents are on the returns, that they are adequate, or even working. Unfortunately, the code required 0-30 psi gauge found on most boilers is useless for the sort of diagnosis you will soon be doing, and so most of us have a 0-3 psi gauge for that purpose.

    When these buildings were built, the temperatures in the apartments would have been only a few degrees different from coldest, to warmest, and the job is to return them to their original state of perfect operation.

    Another tricky feature of any multi building system with a single boiler, is making sure the boiler is not temporarily starve of water as some distant condensate tank is slow to pump the water back.a good steam pro assisted by your observations can get this system back on track for a relatively small per unit cost.--NBC
  • sreja
    sreja Member Posts: 175
    re: Thermometer Heating Survey in my Coop Buildings

    "For years many people complain in the winter that they are either too hot or too cold. "

    Your survey is a nice idea.

    In my condo (14 units) we completely solved all of our uneven heating problems by installing TRVs on every radiator (and replacing all traps, which were decades old).

    I cannot tell you how huge a difference those TRVs have made. Everyone is comfortable now.
  • refields
    refields Member Posts: 45

    Great to hear! Do you have a one-pipe system? If so, what model did you use?
  • sreja
    sreja Member Posts: 175

    we have a two-pipe system, so our choices will not be yours.
  • Bill_17
    Bill_17 Member Posts: 68
    Uneven heating

    If you are in NY and heat with natural gas, there may be untility rebatesor incentives available for TRVs.  Utlity programs vary and a little research is normally required.
  • ChicagoCooperator
    ChicagoCooperator Member Posts: 352
    Nice Job on the plans

    What I did in my building was number each room and then ask questions specifically about that room in a corresponding box. Hopefully people can read floor plans (which seems to be more common in NYC thanks to cooperative ownership which requires floorplans as part of sale documentation).

    Since you might want radiator ID's (size, type, etc), you could figure out (perhaps visiting a few typical units if you can) which was the base or original condition, measure and photograph the radiator and ask, is this your radiator? If yes, check here, if no, measure and describe. That why, you both know what is existing and what has been changed and might need to be changed again in the future.

    Another thing to survey is whether windows have been replaced as a whole or individually. You may want to rewrite your rule book or by-laws to be much more specific about heating modifications if you can swing that - it'll be helpful in renovations, etc in the future and prevent heating problems.

    Good luck and, btw, nice units - they remind me of typical Chicago layouts.
  • HoyteKing
    HoyteKing Member Posts: 85
    suggestion on survey approach

    My building is in the process of conducting a similar survey. What I did was create a special Dropbox file where photos could be posted of all the radiators, etc. That way, all who want to do it themselves can, and others can have it done for them. Feel free to take a look:


    You need to have photos of the sides to tell how many tubes are in each radiator, and count the number of sections.

    Find out what the original boiler was, and you may be able to get hold of an original catalog with all the radiator info (I did thanks to Dan Holohan). Often, the boiler manufacturer made the radiators, too.

    Find out other info on your boiler:

    - compare the install to the manufacturer manual (was the install done right?)

    - is there insulation on all the pipes?

    - are the mains vented properly?

    - what kind of vents are on the radiators?

    Read up on the system using the articles here. They use simple language that even an English teacher like me can understand, let alone an engineer like you. You may need to convince the association to spend some money. Have your facts ready, and be diplomatic:)
  • refields
    refields Member Posts: 45
    Hi All,

    So I put the results together on a spreadsheet for both buildings and the numbers were all over the place. Deviation from average temperature did not seem to follow any particular trends based on floors or apartment lines. Also the average temperature per floor and per apartment line did not follow a trend.

    I am thinking about trying TRVs on my radiator this heating system to see how they work and then possibly recommending them to the rest of the co-op. Is the Danfoss RA 2000 the best system? Also would any suggest a verticle air vent to use which is LESS noisy.

  • Noisy vents are a cry for help from the system, due to bad main venting, and perhaps excessive pressure.
    Instead of analyzing the room temperatures, you must study the operation of the system, as it makes steam. Find out if all the radiators receive steam at the same time. Remember my previous advice: the job is to restore the system to its original state of operation-generous main venting at the ends of the returns, operating at a back-pressure of 2 ounces, during the venting phase. Once you have the steam arriving simultaneously, then there will be some other adjustments to be made.
    Get your order in for a 0-3 psi gauge, and put it on next to the pressurestat, to verify the low pressure maximum which these systems need, and to analyse your main venting capacity.
    Your analysis of the variation of room temperatures has now proved the various levels of discomfort which the occupants now experience, and so show the need for further work.
    Be prepared for a noticeable decrease in fuel consumption, at the end of you efforts!--NBC
  • refields
    refields Member Posts: 45
    My fear with that approach is that I do not want to a) become the person in my coop responsible for maintaining the boiler (keep my sanity) as the folks in my building are not shy about complaining about things they dont understand OR b) find myself falling down the rabbit hole of a complicated project which I wont be able to devote the time to which it deserves.

    That being said - I am not sure how I would ensure all of the radiators are heating up a the same time (I only had about 50% participation in the heating survey mind you). I have confirmed that the steam mains are vented in multiple locations and at the ends of runs.

    Though not the ideal way to solve the problem (which would seem to involve a long term project with many many hours of testing and evaluation) - I would like to see if TRVs make my apartment more comfortable.

    I would like to see if a solution could be to recommend different approaches for different apartments:

    1. For people who keep their radiator turned off because they are usually hot but sometimes get cold
    - Keep radiator on with TRV, insulate riser pipe, better insulation
    2. People who are always hot AND keep the radiator off
    - Insulate riser pipe, better insulation
    3. People who are sometimes hot and sometimes cold
    - TRV, better insulation
    4. People who are sometimes hot and often cold
    - TRV, bigger radiator, better insulation

    Insulation would include carpets, windows, door draft blockers and hopefully cooling other peoples apartments will help alleviate other apartments which are always warm even with the radiators turned off.

    Any sense here?
  • The radiators should have been properly sized for the heating needs of the room in which they are located when first installed, so I would say no radiator enlargement/changeout is necessary. If the system is in perfect balance, then all will receive steam at the same time.
    Main venting is the key, as well as low pressure. The TRV'S may be helpful to a degree, but stil only a partial solution.
    Did you tell us how the boiler is controlled?--NBC
  • gerry gill
    gerry gill Member Posts: 3,078
    Why not put thermostatic radiator vents on the radiators and stage firing on the boiler?
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • Don_197
    Don_197 Member Posts: 184
    Again.....NBC is correct.......the issues your are describing are most likely SYSTEMIC! Starting with TRV's on the terminal units is just flat out a bad idea. If your vents are noisy........you are shy of main venting AND/OR the pressure on the system is much too high (very very common when worked on by people who do not understand steam systems.......I know.....I used to be one of those people). Addressing the main vents, then the individual radiator vents is much more cost effective......will have a much more dramatic affect on the entire system, and will still need to be addressed if TRV's are installed. Listen to the experts......they are experts for a reason.
  • JStar
    JStar Member Posts: 2,752
    Co-ops and steam. What a magical combination!

    I'll have to agree that the main venting and pressure controls needs to be assessed and sorted out before anything else can happen. Once you have a good baseline of steam production and distribution, you can then shift your focus out into the rest of the system/radiators.
  • refields
    refields Member Posts: 45

    The building is over 100 years old and I'm pretty sure significant work has been done (including changing radiators) over the years.

    Nicolas/Don/JStar so much easier said than done when you have 25 units in two buildings and everyone is on different schedules. Like I said I had a hard time getting participation in the heating survey which just involved turning a thermometer on and reporting the data.

    I'm trying to find something that I can actually accomplish which may not be the perfect solution.....
  • refields
    refields Member Posts: 45
    Gerry Gil/Nicholas,
    This is the boiler controller that we have:


    It works based on % on-off time within a 60 minute cycle scaled based on outdoor temperature
  • Don_197
    Don_197 Member Posts: 184
    refields........what we are talking about is the EASIEST portion to access......the pressuretrol (or vaporstat) on the boiler..........and then venting for THE MAINS OFF THE BOILER. Once you know the mains are vented correctly........which MOST times they AR NOT.......and the pressure is not set too high........which most times IT IS.........the difference could be dramatic.....without ever touching anything else. If you still have issues after addressing these two things..........then addressing the vents on the rads is the next step..........and you would have to access those individually if you were installing TRV's as well.
  • RobG
    RobG Member Posts: 1,850
    edited September 2014
    Also, you cannot make everyone happy. Some people will never be happy. 100 yrs ago people were happy just to HAVE heat and never dreamed about A/C. People are spoiled these days. As Joe said "Co-ops and steam. What a magical combination!" Where are you located and who handles your steam work.

  • refields
    refields Member Posts: 45

    Thank you. Do you know of a guide for doing the sort of assessment you suggested (adjusting the pressuretrol/vaporstat and mains venting). I think I will need some help trouble shooting this by myself.

    I totally agree with what you and Joe are saying. That's part of the reason why I fear tinkering with the boiler will make me the person responsible whenever people are unhappy with the heating situation....

    if by "steam work" you mean normal O&M, itis a self managed coop so the boiler controller (Tekmar) settings, and repairs are handled by one of the long-time residents, and he is frequently blamed for heating issues.

    Thanks for the responses and help all.

  • BobC
    BobC Member Posts: 5,473
    Tell the guy who handles the maintenance to feel free to come here and ask questions. These guys are more than willing to share their knowledge.

    I know what he feels like, at one of my old jobs I inherited the job of getting the plant HVAC running and cutting costs when we went through the first oil spike. Make it work, make it run more efficiently, and don't spend any money doing it.

    It can be a thankless job and it helps to have a nice thick skin.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • JohnNY
    JohnNY Member Posts: 3,226
    Is the building in NYC? It sounds like a good project.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    You will need a good steam man with good communication skills to handle this project. Have you tried the find a contractor button here? Where are you?
    How many people realize that there is a problem with this situation-some cold, and some hot, and paying through the nose?
    The ironic thing in your situation is that the solution to the problems will bring such savings that the cost of the work will be paid this winter from the fuel savings, as I see it.--NBC
  • refields
    refields Member Posts: 45
    The building is in Park Slope, Brooklyn

    I have not looked into a contractor but may I will check into our current monthly heating costs.

    Thanks again all.
  • Don_197
    Don_197 Member Posts: 184
    REFields........these guys here can help with what I am talking about every step of the way. Where they live......STEAM IS KING........I am a 21yr experienced HVAC contractor who decided to pick up the minimal business in residential steam here in Spokane WA where no one else would. Venting of the mains is a mathematical equation based on how long and how large...................and the venting of the rads is as simple as venting the far ones fast and the near ones slow........so that steam gets to all of them nearly at the same time.........some people take the size of the rads into account, but you will hear a few arguments about that............but start by making sure the MAINS are adequately vented and you just may be shocked at what a difference it makes.
  • Don_197
    Don_197 Member Posts: 184
    and of course........the pressure on the boiler should NEVER be above 2psi........as a matter of fact........many system run like a champ on 8-12 ounces of pressure.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    I would get a pro in to look things over as soon as you can, and he could make the most simple of adjustments-the lowering of pressure. Possibly, he will find the venting to be inadequate as well. That opens the door to discussion with the other residents as to how much fuel thy wish to save.
    If you have ever had to remove, and reinstall a radiator, you would believe that most of the originals are still in their place, as it is such a hard job.--NBC.
  • JStar
    JStar Member Posts: 2,752
    There's a line in my signature about "guaranteed savings". It's a bold statement, but we've been successful with it by knowing how to balance venting and pressure to make a system really sing. It's a very quick return on investment to upgrade vents throughout the system.
  • refields
    refields Member Posts: 45
    The two adjacent 4-story pre-war buildings share one heating plant in the basement. The combined rough area of both buildings (as measured in google earth) is 7,000 sf. I also attached photos of two angles from the street of the two buildings, and rough floor plans that I pieced together (one for each building typical floor layout).

    Our energy usage in therms for last season are as follows:

    Oct. 13 - 777
    Nov. 13 - 2,997
    Dec. 13 - 3,703
    Jan. 14 - 3,813
    Feb. 14 - 3,929
    Mar. 14 - 2,778
    Apr. 14 - 1,687
    May. 14 - 490

    Does this seem out of whack to anyone?

    Also attached is data from the temperature survey showing the variation in temperatures from apartment to apartment (data for one building apartment lines A and D are in front and lines B and C are in the rear).


  • Don_197
    Don_197 Member Posts: 184
    What is the exact location of the buildings? If you could download degree day info for your neighborhood, and convert your numbers to "therms per degree day" it will give a much better picture AND give you a great baseline on any repairs you make by letting you track energy usage historically.
  • refields
    refields Member Posts: 45
    The location is Park slope, Brooklyn, NY, NY (zip code 11215). Do you know where this information is available?
  • RobG
    RobG Member Posts: 1,850
  • refields
    refields Member Posts: 45
    Thanks! OK so the therms/HDD are as follows:

    Oct-13 3.79
    Nov-13 5.05
    Dec-13 4.44
    Jan-14 3.42
    Feb-14 4.16
    Mar-14 3.26
    Apr-14 3.62
    May-14 3.63

    This is based on the nearest weather station I found to my location (JFK Airport).
  • refields
    refields Member Posts: 45
    Easier to read I hope:

    Oct-13 - 3.79
    Nov-13 - 5.05
    Dec-13 - 4.44
    Jan-14 - 3.42
    Feb-14 - 4.16
    Mar-14 - 3.26
    Apr-14 - 3.62
    May-14 - 3.63