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Add A Rad Pipe Sizing

crash2009 Member Posts: 1,484
A few days ago Mark and Ed pointed out that room 3-A just might be under radiated.  Apparently that was obvious from looking at a picture.  I did a rough heatloss on the room and it appears that Mark and Ed are correct.  I also measured the temperature of the room and it is pretty cool 62-64F.  I think I need to have about twice as much in the room.  I have only 40 installed.  I never thought there would be an upside to having an oversized boiler, but here is my opportunity to kill 2 birds with one stone.  I would like to add 40 to this room.  I have a 2" main, and from what I can see, its 1.25" from the takeoff to the radiator on the 3rd floor. 

I was thinking that I can cut an access into the kneewall to get to the top of the riser. All I can think of to do, is increase the pipesize from 1.25" to 1.50", then runout to both rads and have a good mainvent at the end.  G2?.  

I have calculated what I think I need from Chapter 7 of the Lost Art.  Was wondering if this will work?


  • crash2009
    crash2009 Member Posts: 1,484
    edited December 2011

    there's another way to go after this problem.  What if I forced the rad in 3-A to get hot first and cool off last.  For example, if I shut off all the rads in the whole house, and tried to heat the house only with the rad in 3-A, I am sure it would pressure up to the point of being twice it's size.  Not sure what that pressure would be but it could become 80 EDR at a certain pressure couldn't it?

    Another example, a little less extreme.  What if I installed Gorton 4's on everything except for the 40 EDR in 3A.  I would leave the Gorton D on the rad, and leave the Gorton D on the riser.  This would really upset the balance that I presently have but it would blow up the balloon starting in room 3-A.  3-A would be last to lose the heat as well.  Would it not?
  • Rod
    Rod Posts: 2,067
    Two Pipe Steam Radiators

    Hi Crash-  I'm afraid I haven't be following this and so am not familiar with all the parameters but just thinking outside the box so to speak, is there a possibility of running the radiators on the third floor as two pipe?  (Check the charts page 132 & 133 of the LAOSH)  Using a separate 3/4 return (copper?) , the 1 1/4 as a supply would be plenty big enough. As for the return - terminate it in a wet return or in a loop (Page 99 &100)

    Just a thought.

    - Rod
  • Mark N
    Mark N Member Posts: 1,115
    Add a Radiator


    I think Rod is on the right track. The only problem being it's not going to be easy to get the return lines for 2 rads back to the basement from the 3rd floor. Ideally the rad should be on the opposite wall from the existing rad. I would think having the 2 rads next to each other on the same wall could lead to uneven heating in such a large room. Have you even considered a split mini for this room to handle the heat and a/c and just leave the existing rad as a back-up.
  • crash2009
    crash2009 Member Posts: 1,484
    edited December 2011
    one-pipe puritan

    Two-pipe?  Mini-split?   Well anythings possible, might end up there, as a last resort.  We like to do things the hard way. 

    I was just thinking along the lines of....If you can't get 1 radiator to heat from that riser, How do you think you will heat 2?

    I think I found a small problem with the main and the riser to 3-A.  I still need to check for slope.  There is no insulation two feet upstream and 12 feet downstream of the riser to 3-A. 

    Also the riser going through 2-A is not insulated either.


    I wonder what I might gain by insulating those two areas.
  • crash2009
    crash2009 Member Posts: 1,484
    edited December 2011
    3-A Room Temp

    A few days ago the 3-A riser was tapped and vented with a Gorton D.  The 18 section US Triton improved from 6/18 to 10/18.

    I made a small change yesterday, I removed the plastic door bottom to allow the cold air and humidity out of the room and into the rest of the building. The windows are fogged up less.  It "feels" a bit better in there.  Then I left the data logger in there for the night.  It is interesting to see the results of the temperature survey over time.  The up/down temperature fluctuations coincide with the boiler cycles 20/50/20/50.  In the second pic, it shows that the room is in the 64-65 range most of the time.  There is a significant amount of time in the 65-66 range.  There are occasional 63's and 67's.  

    Todays change was to knock down the venting of the rad beside the 3-A riser from Gorton 5 to Gorton 4. 

    Merry Xmas 
  • icesailor
    icesailor Member Posts: 7,265

    Wonderful things can happen when you insulate pipes.

    Almost like magic.

    Use the Mini-Split as a back-up in the cold weather and AC in the hot. A true win-win situation.
  • Mike Kusiak_2
    Mike Kusiak_2 Member Posts: 604
    Cycling rate

    Wondered if that cycling pattern (20 on, 50 off) was the result of the 1.0 anticipator setting of the T87? As I recall you were cycling more frequently in the last posting of the Lascar plots where we discussed setting it a bit higher than 1.0.

    Did you ever try the 1.1 setting? I am curious if a longer burn time might result in more steam getting up to the 3A radiator?
  • crash2009
    crash2009 Member Posts: 1,484
    edited December 2011
    Slow but steady progress

    I am probably close to 1.1 Mike.  I have been throwing a few other things at the problem as well.  For me, I never know which one thing does the trick.  Over the last couple weeks the rad beside the 3-A takeoff has gone from a Gorton 6, then to a 5, and now to a 4.  Vented the 3-A runout with a D about 10 days ago. 

    Friday Dec 23 made 3 changes.  One or all of these seemed to make the biggest gain for the month. 

    1-anticipator another hair left

    2-Room 3-A door bottom removed

    3-Second floor bathroom window cracked 1 " instead of 3/8"  

    I have identifyed some problem areas:

    1-finish insulating the mains

    2-re-think the venting strategy

    3-possibly add a rad  

    I think I got the anticipator adjusted pretty good now.  3 pics to follow.
  • crash2009
    crash2009 Member Posts: 1,484
    edited December 2011
    Yesterday's results and todays changes

    Results from yesterday's changes.  Temperature in 3-A improved, but so did outdoor temp, so I don't know if I am any further ahead.

    Still trying to hit 1.1 Mike.  If the indicator is accurate that's where I am at.  What kind of cycle are you supposed to get when you get to 1.1  25/55 ?
  • Mike Kusiak_2
    Mike Kusiak_2 Member Posts: 604

    What were the latest changes? Its hard to tell what was caused by weather and what was the result of your adjustments.

    I would leave the anticipator as is for now as you seem to be getting a wider room temp variation. Did you do a cycle plot of the latest settings?  If you can achieve a firing time of 25 minutes, that might be the best compromise between good steam distribution and acceptable swing in temperature.
  • crash2009
    crash2009 Member Posts: 1,484

    The results I posted at 8:44 pm tonight were as a result of changing the vent of the rad beside the takeoff to 3A. I changed the vent from a Gorton 5 to a Gorton 4.  I changed the vent yesterday.  This rad vent was the only change (besides the weather).  The results also reflect the anticipator set to 1.0

    The only change I did today was set the anticipator to 1.1 that was at 8 pm tonight.  The results of the change to 1.1 will be posted tomorrow.  I only have one data logger, it is busy in room 3-A for the rest of tonight.  I will pull the logger from the room in the morning.  Then record boiler cycles tomorrow during the day.  Will post results tomorrow night.
  • Dave in QCA
    Dave in QCA Member Posts: 1,785
    a thought

    Crash, I am curious after looking at your temperature data in 3A, if your boiler cycle is long enough that the radiator is fully heated.  I suspect it is.   If that is the case, you might find that you actually get more heat in that apartment by a combination of 2 things.  One, set the anticipator for shorter cycles.  Two, make sure you have a fast vent on the radiator in 3A, faster per sq ft than the rest of the rads in your house.  This way, most of your cycles will be partial steaming except in very cold weather.  However, in each partial steaming cycle, a larger amount of steam will got to 3rd floor.  For example, you have have a condition when all of the rads in the house heat to 50% and 3A heats to 100%.  You may find that the temps are more even throughout the house as well.

    You probably know, I am in favor on maintaining as constant a temperature as possible.  My steam system usually shows no change at all.  Displaying in whole degrees the readings usually are 71, occasionally they will run 72, but rarely show a fluctuation from hourly cycling.  And of course, the old cast iron hot water system in the house that I live in is a constant 70F.   Never 69, never 72.   The water boiler runs about 3 cycles per hour and there is never any perception that the heat is on or off.  The only change that is perceptable is that the temp of the radiators will be warmer as the temperature outside gets colder.  Everything is gradual and everything is constant.
    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.
  • crash2009
    crash2009 Member Posts: 1,484
    edited December 2011
    3-A Room Temp

    Here are the results of the overnight temperature of 3-A.  The only change from the last set of pictures was that I moved the anticipator from 1.0 to 1.1,,,

    The temperature graphs look a little flat today.  The steam cycles look kinda inconsistant. I think I'll wait for the night cycle times and make a decision tomorrow morning.  But it appears I should adjust the anticipator a half a hair to the right.
  • crash2009
    crash2009 Member Posts: 1,484
    edited January 2012
    The customer is always right

    The tenant reports that the heat in 3-A is much better.  The radiator in 3-A started out December  in pretty rough shape.  Most of the problem was the anticipator setting on the thermostat.  Now that it is set properly to make the boiler cycle 23/53/23 (somewhere between 1.0 and 1.1), the room warms up for a time, then cools off.  More warm than cold.  I do agree that the room is under-radiated, but it is real close.  Some clear roll down shades (we enjoy the view of downtown) would improve the glazing problem alot.  Single pane wood windows just suck the heat right out of that room.

    I removed the weatherstrip from the door bottom to make the room become part of the house envelope,  3-A does not have enough radiation to be a separate entity within this building.

    Insulating the take-off and a small section of main must have helped a bit.  If I get desperate I can insulate the stripper pole below 3-A's radiator.

    Along the way, the rad and runout was re-pitched.  A Gorton D was added to the runout, just before the valve.  The radiator is heating 14/18, instead of 6/18.

    Thanks for all your help!
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