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Paul S_3
Paul S_3 Member Posts: 1,257
Is a condensing boiler always the way to go? For example a series loop baseboard system VS. A old two pipe system with big column radiators. Will the boiler always condense with the baseboard? Thanks Paul St.
ASM Mechanical Company
Located in Staten Island NY
Servicing all 5 boroughs of NYC.
[email protected]


  • heatpro02920
    heatpro02920 Member Posts: 991
    Not always the way to go..

    I have had this conversation so many times, I have friends in the field that think no matter what everyone should be pushing mod cons.... BUT I dont feel the same way...

    First off some customers just want the newest, fanciest, digital, coolness they can afford, which is awesome, I love walking into a sales call and they already looked up mod cons online and know what they want, it makes my job so easy, and I love installing them, they are like little works of art when they are done.... These customers no matter if it will save them money or not, want something special, so they get the value in knowing the unit has a touch face control...

    Its better than the customer with a $5000 TV on the wall and asking if they still sell steel boilers or can they just use a 40 gallon water tank to heat their house....

    Then there are the customers who ask me if it makes sense.....

    Now of course there are those that do make sense, larger home, big heat loops, not over zoned but over radiated {in other words no bathrooms with their own t-stat and there is more than enough emitter to supply the building with heat at lower temps}. If their current fuel bills are high enough to save them money and the system fits what I think a mod con will like, I will tell them truthfully, expect to save X amount per year, BUT you are going to spend X amount more upfront {after rebates}, and X amount more in service, if this still results in a savings, its worth it..

    Then there are 2 other types, one is too small and tight, if I go to a house that is 1200sq ft 2+ zones, well insulated, and the customers are only spending $1400 a year to heat it, I will not recommend a mod con, I will show them that it takes too long for the initial expense to come back and I can not say the boiler is going to last long enough to pay for its price difference over a conventional unit...

    The other type is where the system is just not going to live well, be it water supply quality, small zones, not enough element to run lowish temps, ect... I wont recommend mod cons for properties where it wont be a benefit...

    Some times a nice cast iron boiler is still the best method to heat a home, they go years/decades without service, they last a LONG time, parts availability is all around better {and will be long into the future, try a gen one prestige control in 15 years, but I am sure Honeywell's 8148 will still be readily available or something that directly replaces it}, the initial investment is much less {even after rebates, which are starting to dwindle}, service techs are easier to find, anyone can fix a gas boiler, some of the mod cons can get tricky, even with the controls that tell you what is wrong... There are a lot of reasons to go std boiler, and only a one to go high efficiency - Future savings, but when you break it down, and maybe add interest to that extra upfront cost the mod con carries with it, they start making less and less sense...

    I always compare it to a car, if you travel 6 miles a day is it worth spending an extra $14K on a hybrid vehicle, maintenance is more expensive, initial costs are higher, the technology is not perfect yet, ect... A decent car gets 33mpg a hybrid get 42mpg, you start doing the math and that car cost you more even after the government gives you $3K back {not sure if they still do that}....

    Which leads me to the next customer, the one that wants to save the world, my wife drives a hybrid, and it makes her feel better about herself, that is great, she is obsessive about recycling and hasnt eaten meat since she was 7 years old, eats no animal foods at all and wont wear wool or leather, its all wonderful, so if your customer wants to save the world then they should have the unit with the smallest carbon footprint, as I told the TT rep a while back, "you should figure a way to mark these things "MADE WITH 100% RECYCLED MATERIALS" It would sway some peoples decisions for sure... For these customers, the savings is a moot point, and that is great, I on the other hand, unlike my wife, like to know where my money is going and like to hold on to as much of it as possible...

    In closing, I have a mod con in my home, and almost all of my rental properties have 95+ units and rinnai water heaters... But I obviously didn't pay for installation...
  • icesailor
    icesailor Member Posts: 7,265

    Tell them that cast iron boilers are made mostly of recycled steel that at one time, was iron. over 90% (I've heard 95%) of copper tube is recycled.

    PEX isn't.

    So, use cast iron boilers, piped with copper. GO GREEN.

    See what they say when you give them the price for copper.
  • heatpro02920
    heatpro02920 Member Posts: 991

    I still have customers that only want copper, they don't care about the cost and I don't push it. Sometimes I miss soldering, I still do a lot of it, but not like 10 years ago, it seemed like all I did was solder 7-10 hours a day, I can not count the rolls of silverbrite these hands have unrolled, but its a lot less now.... I am waiting for them to make some fancy plastic for near boiler piping, super thick and threadable, pre insulated, pick your color to match your boiler or a different color for return and supply, molded in circ flanges.... If steam wasn't disappearing that would next, plastic steam piping, pre insulated with mechanical fittings...
  • SWEI
    SWEI Member Posts: 7,356
    Without getting into the philosophical points

    which I quite enjoy at times, it really does depend.

    In our part of the world, ridiculously cheap ($0.60 per therm) NG, relatively mild climate and abundant winter sunshine make the payback on truly high efficiency boilers rather unattractive.  On larger houses and commercial properties, not so bad.  For the LPG customers, a slam dunk.
  • M Lane
    M Lane Member Posts: 123
    Efficiency mandates

    I've done a lot of work in Vail, CO. They mandated 93% minimum efficiency on all new and replacement boilers. Not everyone up there can afford that. Its funny thinking that installing a boiler can be a criminal act. I wonder when they will start issuing warrants to go into peoples homes and see if they are compliant.

    Personally, I try to separate the functions as to what I'd recommend. If you need a high setpoint, like with baseboard, I'll push for a 83% unit. Mixed or low temperatures I'd rather go Mod Con than relying on mixing valves or injector pumps.

    I personally am a fan of Allied Engineering's Super Hot line, mainly with the steel tube heat exchangers.
  • CMadatMe
    CMadatMe Member Posts: 3,086
    Heat Loss Heat Loss Heat Loss

    Your question is very broad. I'll take the path of do the heat loss, measure emitters and calculate water temp needed to provide btu/hr to overcome the heat loss on your design day. Make the decision from there. Most homes are 35% over radiated so in many cases yes it does make sense to go mod/con.

    Every job is its own and should be treated as such.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • icesailor
    icesailor Member Posts: 7,265
    Boilers & Baseboard:

    IMO, I would always install the Mod/Con if I could sell it. If the installed base board was sufficient to heat the building, and there have been "improvements" to the building that cut down on heat loss, the baseboard/emitters are larger than what the original design was for. If the design was zero outside and the inside is 70 degrees, and it is only 35 degrees outside, the emitters are twice what they need to be. Therefore, if a room needed 10' when it was zero outside, the emitter only needs to be 5'. Or the water temperature drops to accommodate. Because there are only few days when you need full power, the radiation is always bigger than it needs to be, or the water temperature is too hot. But you get faster pick-up.

    What Mod/Cons need but don't have, is the ability to ramp up to higher fires when the thermostats are not satisfied, and ramp down to the local load at the time. When someone does that, Mod/Cons will be the only choice in residential and light commercial installations.

    More like over riding ODR.


    Every cold house I ever worked on was resolved by tightening up the heat loss/infiltration. The Mod/Cons all go to high fire for DHW priority. It can be done. No one had done it, YET.

    Get on it.
  • knotgrumpy
    knotgrumpy Member Posts: 211
    Allied Engineering

    Their mod/con looks exactly like a Triangle Tube Challenger.  I think TT imports that one from Europe as well, don't they?

    Anyone have experience with the design?
  • SWEI
    SWEI Member Posts: 7,356
    Ramping up

    sounds a lot like the "boost" feature found in many mod/con controls.  If heat call is not satisfied after X mniutes, raise supply temp by Y degrees.  Repeat until call is met or high limit is reached.