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Undersizing

Tom_133
Tom_133 Member Posts: 883
So, I am thinking I know the answer to this question but I don't mind feeling a bit dumb.

JStar will know a bit about this since he looked at the job a while back. I have a customer who needs a new steam boiler, and I had Jstar come up and look at it. He came up with an EDR of 1064sqft, so his quote was a peerless 6 section, which seems to nail it. The current boiler is a bit undersized I believe its an older weil mclain (don't know the exact specs) and the oil provider showed up and quoted a new boiler, a peerless 3 section with a 1.20 which if I have this right is a EDR of 446sqft. Am I missing something? I am not a steam guy but it seems to me like that boiler will run and run and run.

I told the homeowner he better hold off til I have time to ask a few steam guys. Am I correct, will that baby just run for too long?
Tom
Montpelier Vt

Comments

  • Fred
    Fred Member Posts: 8,542
    If the radiator EDR is 1064, there is no way a Boiler rated at 446 sq. ft. will do the job at all. Several on this site would suggest you could undersize by 10%, maybe even 20% and it would still be OK, given the added Piping and Pickup factors that boiler manufacturers build into the boiler that is not reflected in their ratings. That 10% to 20% may be OK, depending on how much piping you have that needs to be maintained, temp wise and how well thatt piping is insulated but you are talking 60% undersized and that would be a disaster. It just can't keep up with the demand. The house will always be cold on days when the outside temp is anywhere near design days for that area.
  • vaporvac
    vaporvac Member Posts: 1,520
    This is really strange because all the hacks want to oversize the boiler all the time.
    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
  • JStar
    JStar Member Posts: 2,752
    edited May 2015
    If I remember correctly, I only added 20% for a pickup factor. I liked the slightly "oversized" 6 section to promote more efficient heat transfer into the water.
  • Fred
    Fred Member Posts: 8,542
    It would make sense if the oil provider suggested two boilers at 446/ea., configured so one or both fired as needed. I doubt that he considered that but I can't think of any other reason he would have suggested anything that small.
  • Tom_133
    Tom_133 Member Posts: 883
    Good to hear I'm not missing something completely, The oil providers price is very, very low that's the only reason he's considering it. I mentioned that if he can get it all in writing all parts, boiler, near piping, and controls are new and can assure him that at -20 it will maintain 70 inside than do it. Though I did also tell him, I don't want to hear the crying in February, you are getting what you pay for.
    Tom
    Montpelier Vt
  • j a_2
    j a_2 Member Posts: 1,801
    Can u post up the edr worksheet....How big is this place?
  • KC_Jones
    KC_Jones Member Posts: 5,722
    Is the customers choice JStar or the oil company? If so send the customer here and we will explain to them the difference. They will get what they pay for. If they go cheap they shouldn't expect comfort.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • JStar
    JStar Member Posts: 2,752
    edited May 2015

    If you use the SC-06 you have to downfire it from 3.50 to 2.55 GPH to get down to a 20% pickup factor. Quite a drop.

    Even the SC-05 would need a downfiring from 2.80 to 2.55 to get the 20% pickup factor. It's "slightly" oversized.

    I'm referring to the ECT model, not SC.
  • jonny88
    jonny88 Member Posts: 1,139
    Am why is there a question as to what Jstar is recomending.Go with him and call it a day.As you can see he is up here with the elite in steam and you should consider yourself lucky that he is involved.My two cents.
    RobGKC_Jonesj a_2
  • Tom_133
    Tom_133 Member Posts: 883
    For me there is now question, you go with a true professional hence the reason I had Jstar come up in the first place. As for the customer he is looking at a 50% up front savings and a written guarantee that it will work and if it does not they will do whatever is required to make it work. That is hard to argue against, I have explained this to my customer but I think dollars and cents will win out over all other sense.
    Tom
    Montpelier Vt
  • KC_Jones
    KC_Jones Member Posts: 5,722
    Tom said:

    a written guarantee that it will work and if it does not they will do whatever is required to make it work.

    Does that include completely changing the boiler when it can't heat the house? I would want that contract to be very specific.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • j a_2
    j a_2 Member Posts: 1,801
    I am sure jstar will size it correctly, its far more of a problem for him than you, believe me...I am sure he will install at min. A proper header , to size, or better...He will relocate main vents as required, repitch any pipe needed, and will replace all radiator vents...He will provide a skim port and USE it..He will also be able to explain the entire operation of the system without having to google answers, or call Daddy boss. He will I am sure add his personal touches to his install, not sure if he does dropped headers as a standard install....I am sure he will support any and all manf. warranties, as well as warrant his mechanical work for many years...The list goes on and on, most of what you get from a pro is just plain old standard practice, to us....It really is a minor investment to your home, but a very important one. A standard 8 k job to a 400.00 house is such a small percent...and it will last 30 years.....Go with jstar and relax


  • JStar
    JStar Member Posts: 2,752
    To be honest, paying 50% less and having a guarantee that they will install the correct size boiler and proper piping when the heat doesn't work the first month sounds like a really good deal. You'll put that company out of business real quick!
    Charlie from wmass
  • j a_2
    j a_2 Member Posts: 1,801
    Me personally have never had an issue with a company u s boiler included that went unresolved.. The guys up here are beyond helpful. Meaning the reps ...If they know your work they bend over backwards to help.....Big problem is the shareholders vacatioing in Florida with all their profits ,made off us the little guys...All reps offer training and it were me making the decision it would be mandatory....
  • jonny88
    jonny88 Member Posts: 1,139
    Did a repipe for a ex cop after sandy.You wouldnt believe the install unless you saw it.We cut everything out.He went after Lic plumber and plumber got his lic revoked and the customer is still going after him in small claims.Did not get his money but is still pursuing.
    Charlie from wmass
  • SWEI
    SWEI Member Posts: 7,356
    The realities of the US distribution system and our legal climate make it pretty much impossible for a manufacturer or importer to enforce any actual requirement for approving installers. There are some workarounds with extended warranties, but I understand even those have been successfully challenged in some states.
  • JStar
    JStar Member Posts: 2,752
    I was part of a legal arbitration involving a bad boiler install. The customer won the case. In the end, the customer lost money, but pushed forward on principle. The whole process was drawn out and ugly. Our current system makes it way too easy to become frustrated and drop cases against inept contractors.
  • Fred
    Fred Member Posts: 8,542
    edited May 2015
    @Tom , Why not ask the homeowner to visit this site and this string and see what others have to say about the sizing issue?
  • Tom_133
    Tom_133 Member Posts: 883
    Fred, This customer is a very reasonable and honest guy. He wants the best deal for the money and quite frankly if it was a difference of 5k or less he wouldn't have thought about it at all would have just pulled the trigger.

    Jstar is the man with steam and I expect after his install there wouldn't be any problems with the system.

    This local company is one of the bigger companies in the area and though you may be correct, they may run away I would doubt it.

    I don't believe the other company will be doing a drop header, and will probably do only the bare minimum to satisfy manufacturers specs for piping, but I have been reading up on steam and will be checking everything with a fine toothed comb.
    Tom
    Montpelier Vt
  • SWEI
    SWEI Member Posts: 7,356

    SWEI said:

    The realities of the US distribution system and our legal climate make it pretty much impossible for a manufacturer or importer to enforce any actual requirement for approving installers. There are some workarounds with extended warranties, but I understand even those have been successfully challenged in some states.

    You know what would solve the problem once and for all?

    If the manufacturer had franchised installers to perform the work. Just like a car dealership.
    ...
    The manufacturer has complete control over these franchisees and can ensure that a quality installation is done. Furthermore, these entities can stock a far greater selection of parts than any independent plumber could ever do.
    I have seen this approach used in several trades, past and present. It requires significant commitment from the manufacturer or importer (sales, training, and upkeep are not cheap) and often ends up having the effect of shutting smaller contractors out of the market entirely. I'm not saying it's inherently bad, but it does make for a real challenge getting your product into smaller markets and tends to create entrenched monopolies in medium to large markets. Some kind of master distributor hybrid model might be able fix this, but I'm still waiting to see a really well-run example.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    The flat roofing trade is one industry where the installation has to be inspected before the manufacturers extended warranty is issued.
    In the case of heat-welded PVC, an inexperienced installer could overcook the material.--NBC
  • Fred
    Fred Member Posts: 8,542
    As it relates to this particular proposal, a boiler that is 50% to 60% under-sized isn't going to work, regardless of who installs it or how it is installed. This may well be a case of "Bait and Switch"
  • Tom_133
    Tom_133 Member Posts: 883
    One last question, sorry to bug you guys.

    Lets say the building has radiators that equal 1064sqft, but the building doesn't require half of that. Would a boiler with 550sqft heat a building with 1064sqft if 550 is all that's needed?

    I ask because this oil company that gave the quote said they have been under firing the current boiler for a while and the building always heated well. I am not suggesting this was the most economical way for them to do it, I just want to get some more info so I can retort appropriately when I talk with them.
    Tom
    Montpelier Vt
  • j a_2
    j a_2 Member Posts: 1,801
    Honestly you got some very good answers here...probably time to make ur decision based on the information at hand....Wish u the very best of luck, go with your head not ur wallet
  • j a_2
    j a_2 Member Posts: 1,801
    Just make sure you get in writing, and they spec they are accountable...
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    Tell us the pump pressure, and the nozzle size, and we can deduce from that the final BTU the boiler has been firing at.--NBC
  • ChrisJ
    ChrisJ Member Posts: 15,592
    If it was me I'd use @Jstar and no one else.

    I've seen too many people have someone install a steamer wrong and then fight over it and the customer always loses. It also seems like the answers are always the same. "Steam is supposed to bang, it's just the way it is".

    With Jstar you're guaranteed a good install, no headaches, no fights in court etc.
    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
    RobG
  • Fred
    Fred Member Posts: 8,542
    edited June 2015
    With a boiler half the rated size of the Radiator EDR, None of those radiators are going to heat enough to be effective at heating a space and because steam will take the path of least resistance (and there will be a very limited amount of it) balancing the system will be next to impossible. Expect a nightmare. Also, they may have down-fired the current boiler but I'd bet it was rated at more than the 1064 sq ft. of radiation. You can only down-fire so much. No where near what they are proposing. JStar is a proven commodity! You get what you pay for. I just hope this HO understands that next winter when he is trying to get his heating problem resolved.

    EDIT: How big is this building (Sq. Ft.?) Are they proposing taking out half the radiators?
  • Paul48
    Paul48 Member Posts: 4,469
    Their reasoning for down-sizing is flawed. They may have down-fired the previous boiler, but the surface area of the water in the boiler allowed for the production of steam, adequate for the radiators. It just took longer. Smaller won't fly.
  • Tom_133
    Tom_133 Member Posts: 883
    Gentlemen,

    Thank you, I will give my customer this info and will try to update you on any progress.
    Tom
    Montpelier Vt
  • JStar
    JStar Member Posts: 2,752
    Keep me in the loop. I'd be willing to look at some other options.
    RobG