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Mod/con poll. Installers only.

STEAM DOCTOR Member Posts: 1,368
Good afternoon. I have finally crawled out from under my bed. The last mod/con post turned out to be a little bit more then I expected. I would like to propose a simple poll.

Setting: Customer with heat load of 125000 BTU. New York City(i.e. long heating season). Old house. Not much insulation. High temp baseboard.  Needs new gas hot water boiler. Wants to know your opinion on cast iron boiler boilers vs. mod/con.

Do you tell him

1) No brainer. Go for the mod/con.

2) No brainer. Go for the cast iron boiler and use any extra money for other energy saving upgrades(insulation,outdoor reset etc.).

3) Tell him that its not black and white. Tell him all the pros and cons and let him decide.

Rules of the poll:

1. Poll is open only to installers(not homeowners,distributors, company reps etc).

2. The only answers allowed are 1, 2, or 3. No explanations or other dialogue allowed.

3. Please detail approximately how many RESIDENTIAL mod/cons you have installed and how long you have been installing them for.


  • RobG
    RobG Member Posts: 1,850

    Sorry that your last post on the subject got a little off topic. I would go with option 3, envelope upgrades are as important as an efficient boiler. Once the envelope is tightened the boiler can operate at a lower temp utilizing the efficiency. Always give options, that keeps you in line with all the other guys and sets you apart. I would try and stick to the fire-tube heat exchangers for mod-cons. They are tried and true and give great flow rates.


  • Zman
    Zman Member Posts: 6,958

    You can't simplify it quite that far.

    There is a huge difference between a system designed to run on 180 degree water vs 120. How is it  zoned? What is the energy cost? How difficult is it to repipe the vent?

    For some owners it would be an obvious answer 1 for others absolutely 2. For a handful of jobs it is truly a coin toss. Your job is to evaluate the job and make a recommendation.

    Sorry about the rules

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • SWEI
    SWEI Member Posts: 7,356
    edited July 2014
    Analyze first

    #3 with explanation:

    Have you done a room by room heat loss and radiation survey?  Don't forget to add some window coverings to the U-values (most of us close our blinds or drapes at night.)

    What water temp will be required on a design day?  Are the rooms relatively well balanced with the existing radiation?  If just one or two rooms are under-radiated, consider increasing radiation or upgrading the envelope in those rooms (sometimes all it takes is some better window coverings) to better balance the system and lower the overall system water temp.

    Is there any "low hanging fruit" in the existing envelope?  What would that do to the temp requirements? and are worth a few minutes of your time.
  • Rich_49
    Rich_49 Member Posts: 2,607

    Well if I have to recommend one it would be #3 .  Lots of radiators in NYC and area .  Don't forget dirt seperators when you do use a modcon , all the trash will plug up an HX quick in stock that old . After you determine heal loss and what the radiation is capable of you can make your recommendation . Don't be scared of 180* SWTs though if using ODR because running a 40* Delta with radiators will have you condensing for a real good portion of the season.
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • clammy
    clammy Member Posts: 2,665
    # 3

    if the chimney is good and even not go with #3 as long as you have the correctly sized boiler for design day .I think the mod con business is still on a installer /HO  learning curve and with out the correct heat emmitters TD across the system and proper od reset it s a waste  .The supply house support across the board is not what it should be wheather its a ci boiler or mod con makes no difference .Plus who s got money for any of it this by far is the worst year yet and who would want to waste money on something that is going to cost you all money you saved on energy for service and repair with a 10 to 15 year life span .At least it may last you longer then a new car .I started installing then with the munchkins and still have them running but irate HOs not wanting to pay for yearly service sucks the only ones that do not complain are the oil to gas conversions jobs aside from that its a 50 /50 crap shoot.Thats why I basically went back to ci boilers /ps piping and properly sized and have had a lot less headaches and a lot  less cost acciocated loses from free service but if you don t do service and just toss them in then it s good .Aside from the above rant heres a few more no one wants to pay for a Combustion anz,unless CO alarms are going off ,no one wants to pay for anything more then baseboard nor will supply house stock or carry any thing more then baseboard no panel rads ,And #1 no one including supply houses who do design and do  heat loses which sells you your mod con they will not design a system for low temp to operate properly or truly eff for the boiler .Sell mod cons to preppies with money who hug trees and don t mind coughing up 300 to 500 each year for service and in some cases enjoy seeing your face when they have no hot water or heat .Like all equiptment proper service is only done when the unit is properly installed so one can service it that means following the installation instructions and understanding what clearances are needed to clean and service the unit.Aside from a bunch I have installed I have seen more that needed service but could not be performed due to crap installation with no clearance.So just like putting your foot in a real hot bath tub and pulling it back out realize that the true winners in the mod con buz is the manufacture and the lucky contractor who installed got paid and faded away .Just rant the truth in a society that will cram there convecitions down your throat kinda like socialism  .Just stiring the  melting pot .Still dragging my chimp like paws on the ground while eaten bananas and swingin one armed peace and good luck clammy should have had de caf this am
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • Tom_133
    Tom_133 Member Posts: 766

    I am probably an over explainer, but I like customers to be informed and make the best decision possible with their money. Same way I like to be treated when embarking on an unknown purchase.

    If they get hung up and can't choose and want my input I tend to go with what I would do if it was my own home.
    Montpelier Vt
  • Al Corelli_2
    Al Corelli_2 Member Posts: 395


    I've got Hundreds under my belt.

    Been Installing for over 30 years.

    Hi Clammy!
    Al Corelli, NY

  • Bob Gagnon plumbing and heating
    Bob Gagnon plumbing and heating Member Posts: 1,361
    edited July 2014
    In Massachusetts

    It's easy, the chimney liner and rebate for mod con , makes 1 the correct choice. Add more baseboard to get your operating temps lower, and tighten the buildings envelope for optimal energy savings. I have been in business for 35 years, installing mod cons for eight years.

    Thanks, Bob Gagnon
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • gennady
    gennady Member Posts: 830
    edited July 2014
    Condensing boiler.

    #1 No brainer. No matter what.

    Mod cons are the best thing happened in residential heating in last couple decades. Modulation of boiler output is standard on commercial boilers and application of modulation in residential segment is really amazing development. Condensing will always happened when boiler is properly set up. I seen boiler condensing at temperatures way higher than 132F return. There is common believe that condensation happens only at dew point.

    I always install dirtmags, do water cleaning and conditioning. X100 and X 400.

    I stick with viessmann, don't want to deal with reliability issues

    And what is the difference, CI radiators, baseboards, or what ever. It does not matter.

    I always install VFD circulators on system side. Constant flow the way to go.

    Wait, no thermostats, no zoning.
  • JStar
    JStar Member Posts: 2,752


    We don't install low-efficiency anything. It's just not our style. If properly installed and maintained, the mod/con will deliver all of its promised results with the same amount of maintenance and service as a CI boiler. Yes, SOME of the parts are more expensive, but that's the risk we take for improved comfort and fuel consumption. I see it as a good reason to get your customers signed up on a service plan that will dramatically decrease their service costs.

    Plus. natural draft is an evil mistress. I'm all for anything that uses sealed combustion and releases a home from the inefficiency of a chimney.
  • radmix
    radmix Member Posts: 194

    I would like to say #3 but when a customer calls with no heat and the boiler needs to be replaced and they have a very low budget you cant tell them to insulate and replace there windows before I install there new boiler, they'll be off to the next.