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Is a high efficiency boiler worth it?

CEP
CEP Member Posts: 9
Replacing my old boiler and considering a conventional boiler vs a H.E. Model and have heard that even with rebates the H.E. Is not worth it as it may have to work much harder to heat the house and require more in maintenance costs. I have a split entry built in 1973.
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Comments

  • Rich_49
    Rich_49 Member Posts: 2,766
    edited August 2015
    Seems to me that an 85% boiler would have to work harder to deliver 100% of the heat than a boiler that has an efficiency or AFUE of 90+% .

    Me thinks you are talking to the wrong people or just people who don't quite understand or cannot install the equipment .

    As far as maintenance costs go , this does not have to be so . There are plenty of different HX configurations that dependent on choice maintenance does not have to be such a big issue .

    Keep talking , tell us where you are located and some more about the house . I'll bet the people you are talking to also would put the same size , quite probably twice as big as needed boiler right back in there .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
    Bob Bona_4Canuckerjonny88njtommy
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    Rich is so right. Some brands can take 4 hrs to clean, others less than an oil boiler. I've embraced mod cons since 2002.
  • j a_2
    j a_2 Member Posts: 1,801
    What type heat emitters do you have, and how many zones? Is there a proper area to install the venting? is this unit going to handle heat and hot water, and if so is it a combi unit or attached indirect. and if not are you going to orphan your existing gas water heater? There are lots of questions to answer before, your questin can be answered...Start with answering these...
  • j a_2
    j a_2 Member Posts: 1,801
    The correct answer will be, the boiler that best matches you homes situation...To me there is no carpet answer as to what boiler is best,,,,just depen
  • CEP
    CEP Member Posts: 9
    Thank you for the responses. I should have been more specific. We have approx. 130 ft of baseboard forced hot water heating pipe that you can see. Two zones (standard split entry) w/ about 1,200 sq. ft. Upstairs and less downstairs due to the garage under, closet /storage space under the stairs, and small boiler room. 2 1/2 baths. Currently have an early 1970s boiler and 50 gall direct water heater. Looking to replace both with a boiler/indirect hot water tank that will last a long time and be cost effective/ low maintenance. Thank you.
  • CEP
    CEP Member Posts: 9
    $1.26 / therm
    ~ $1,210 last 12 mo.
  • CEP
    CEP Member Posts: 9
    Perfect- thank you
  • j a_2
    j a_2 Member Posts: 1,801
    I totally agree..that its not a good fit, but that is just my opinion based on the information you provided. Remember your looking for comfort,. If you choose to chase rebates it may dicate your decision Think with your head not your wallet
    JStar
  • ChrisJ
    ChrisJ Member Posts: 15,588
    If it was me, and I had to put in a new boiler anyway I'd go with a high efficiency one if I had the option. We don't have that option with steam, at least not yet.

    If my boiler was around 80% AFUE and it was fine I'd leave it alone until it needed replacing.

    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
  • Rich_49
    Rich_49 Member Posts: 2,766
    That is assuming a SYSTEM efficiency of 76% , not typical .
    There is alot more to consider .

    The home is 1200 sq ft approximately . If it is a sieve with a 30 BTU per sq ft requirement the design heat loss is around 36,000 BTUh . You have 130 feet of baseboard by your account . With 130 feet each foot would need to produce 276 BTUh . That would tell me that at design we need 140* AWT through the baseboard . So for 2% of the heating season you are just condensing with a 20* fluid Delta T but for 85% of the season you will condense well and be achieving 92+% AFUE .

    Remember also that you will not have stack losses like a cast iron boiler which accounts for quite a few dollars and let's move the fluid only as fast as the load at any given time requires with an ECM Delta T circ so we get every bit of work we can out of the fluid . That also adds efficiency to the system . Wait , we forgot that we have ODR which by the way is required on all boilers now as of Sept 2012 , that or thermal purge on units lower than 85% which ids also minimum AFUE .

    In short an 85% cast iron boiler will short cycle like a monster every minute it is in service . The controls necessary to make it acceptable by code minimum will cost extra dollars . You probably won't be able to use the low water temps and if you do your boiler will not last as long as the last one .

    Last but not least you could use this and have to do little maintenance and any **** can probably pull off the install .

    http://www.htproducts.com/pioneer.html

    A boiler that turns on and off several times an hour is working hard kimnda like city driving . A boiler that comes on for 15 minutes per hour or 2xs an hour is not working hard . Lower water temps and proper minute by minute flows based on system needs are real game changers .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
    ChrisJBob Bona_4
  • ChrisJ
    ChrisJ Member Posts: 15,588
    Bob Bona said:

    Let's not ignore combustion air and chimney liner issues ($$) that are to be considered with a conventional boiler replacement. All moot with mod con's.

    Of course you do open up the whole "shouldn't use PVC for venting" argument and possibility lawsuits from what I've heard on here.

    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
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    There's other venting material options for the anti pvc crowds.
    ChrisJj a_2
  • ChrisJ
    ChrisJ Member Posts: 15,588
    The increased comfort is a big plus. Essentially reducing your radiation must be a beautiful thing.
    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
    Bob Bona_4
  • Rich_49
    Rich_49 Member Posts: 2,766
    The fact is that you will save more along the lines of 30-40% in fuel when treated as a system as opposed to a bunch of parts .
    Use PVC for the intake air and PP for exhaust .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
    Bob Bona_4HatterasguyRobG
  • ChrisJ
    ChrisJ Member Posts: 15,588
    Rich said:

    The fact is that you will save more along the lines of 30-40% in fuel when treated as a system as opposed to a bunch of parts .
    Use PVC for the intake air and PP for exhaust .

    Same rules for steam, it should be treated as a system.
    I guess that applies to all HVAC systems, even forced hot dust.
    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
    Bob Bona_4
  • j a_2
    j a_2 Member Posts: 1,801
    You got some good advise here and I hope it helps in your decision... And you have years of comfort for your investment...Many of us differ on opinion here, that's just how it is....Hopefully you select an installer that knows what the heck he is doing....Bottom line is safety and comfort... Best of luck
    RobG
  • CEP
    CEP Member Posts: 9
    Wow! Thank you all for your time and advices. There is a lot to digest here, but I think I'm going with the conventional setup.

    JA, what u said was consistent with the plumber we liked most, made the most sense, and was the most patient and detailed-oriented in his evaluation. He was also the only one who measured out the baseboards.

    Thanks again!
    ChrisJRich_49j a_2
  • Rich_49
    Rich_49 Member Posts: 2,766
    edited August 2015
    Measured out the baseboards ? Is that how he came up with your heat loss figures ? STOP , HOLD IT RIGHT THERE . If this is how he came up with the sizing of your boiler you NEED to find someone else . i am sure he is very personable but a heating designer he is not . This is not the man you want designing a system for you . Where are you located ? Please tell me what size boiler he stated that it is you require also .

    Way to go JA , unwittingly you set this guy up for a disappointment . You should help change his mind .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
    ChrisJj a_2Bob Bona_4Jean-David Beyer
  • Rich_49
    Rich_49 Member Posts: 2,766
    edited August 2015
    An 85% cast iron boiler with ODR control or thermal purge (required) by National boiler code enacted in September of 2012 will run you a couple grand or just shy of . The mod con I linked to will run about 1/3 more and everything you need is there .

    I build systems as does any technician actually worth a damn . Just manadging flow and delivering the heated fluid properly can save loads , of course that will vary from home to home . 140* is not a pipe dream . based on a 1200 foot home with 130' of baseboard and eliminating the jack and the Beanstalk HEF and using 85% of the rated output it is totally within reason .

    I think you give these old cast iron pots more credit than they deserve my friend . 65% is a dream in that world , problem is the amount of boiler rooms you've attended and the number of gas bills you have seen from customers .

    a simple well thought out pump replacement job can save more than what you are stating .

    http://jbblog.flopro.taco-hvac.com/delta-t-dawn/
    http://jbblog.flopro.taco-hvac.com/anthonys-voice/

    These are real life stories , not just some math with no basis except funny AFUE numbers . Systems are awesome , boilers are just boilers .

    Again , you are advocating bad design practice by using fuel usage from a POS with an unknown overall system efficiency and again I say that is no way to perform boiler sizing or a heat loss . This is how real heating men perform heta loss and design , even on long Island , unlike others .
    http://mechanical-hub.com/sites/hydronics/botto-brothers-plumbing-heating-watersteam-boiler-installation/

    Take into account that a 180* boiler will have astronomical stack losses after the 4 minute run time while the mod con will have little , especially due to the fact that it can accept low return temps which increase the efficiency and lessen stack losses . That cast iron boiler will continue to fire little short cycles exacerbating that issue .

    Most of the year ( Oct - mid Dec , mid Mar - mid May) the mod con will be able to use 120* water or even lower while the cast iron boiler is not capable of that . Those are the times that the efficiency pie really gets messy . Making 180 water when 120 will do nicely and firing numerous times because the differential tells you to , while the 55 gallon mass mod con may get you through 2-4 hours on one burn . That 3 1/2 months of serious inefficiency is what will bite you in the **** . wanna make a cast iron boiler less efficient ? It'll cost you more in parts and labor than the mod con , but hey , your basement will look like a really cool rocket , right up your alley .

    Now let's see if the OP tells us what size boiler was recommended for his 1200 sf house with 130' of baseboard and maybe we can save him the headache he is certainly headed for with the guy who sized him up by measuring the installed radiation . Ya think that's worth a shot ?
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
    RobG
  • ChrisJ
    ChrisJ Member Posts: 15,588
    What's the efficiency of an 82% afue boiler firing at a 25% duty cycle?
    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
  • ChrisJ
    ChrisJ Member Posts: 15,588
    2 cycles per hour 25%
    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
  • ChrisJ
    ChrisJ Member Posts: 15,588
    7.5 on 22.5 off
    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
  • j a_2
    j a_2 Member Posts: 1,801
    Well best of luck on your install....Let us know how it went...I am sure you will make the right choice....

    ..
  • j a_2
    j a_2 Member Posts: 1,801
    Rich,you made a comment I set the guy up for failure...Why on earth would you think or say that..My opinion is based on the information provided...Maybe just maybe the guy measerd baseboard to do a room by room heat loss...and hopefully not as you think to size the boiler..Maybe he as well is taking into consideration the flow rates required on the 50 gallon indirect....Maybe he is in a low pressure gas area and can't meet the min.required for a mod con...Maybe the guy has no good area to sidewall vent...There sir is a lot more to consider than just running a bunch of numbers on a spread sheet..Me, I never would TEll someone what to do site unseen..., but I can give my opinion...You by chance are not the installers competition,are you....I was a bit surprised that you would publicly state I set someone up for failure..That is a wee bit unprofessional
    Rich_49RobG
  • JStar
    JStar Member Posts: 2,752
    Theoretical numbers are great and all, but I can pull out my customer's fuel bills and prove my claims.
    Bob Bona_4Rich_49
  • Tinman
    Tinman Member Posts: 2,808
    I'll install the occasional cast iron boiler for a number of reasons...sometimes it just may be elderly clients who have plenty of money but are use to a certain way and I respect their wishes. I'm not doing this to force my agenda down anyone's throats.
    That said, 8 of 10 or so we sell/install are mod cons. I love the progress they've made in the last 10 years or so and just because something has a warranty of 12 years doesn't mean it won't last 20 or more.
    How many AC units with 5 year compressor warranties are still out there running at 20 years?
    In my humble opinion, there's room for both.
    Steve Minnich
    JStarBob Bona_4RobG4Johnpipe
  • ChrisJ
    ChrisJ Member Posts: 15,588

    I'll install the occasional cast iron boiler for a number of reasons...sometimes it just may be elderly clients who have plenty of money but are use to a certain way and I respect their wishes. I'm not doing this to force my agenda down anyone's throats.
    That said, 8 of 10 or so we sell/install are mod cons. I love the progress they've made in the last 10 years or so and just because something has a warranty of 12 years doesn't mean it won't last 20 or more.
    How many AC units with 5 year compressor warranties are still out there running at 20 years?
    In my humble opinion, there's room for both.

    20 years?
    Pffft. :p
    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
  • Matt_67
    Matt_67 Member Posts: 284
    For small cast iron boilers slant fin makes the sentry model in a 34k input. Something else to factor when running the payback calcs on small systems is electrical usage, especially if the mod con requires a boiler circulator. Also - determining capacity of the installed radiation is an important part of evaluating a home but a heat loss must also be done. The other aspect of choosing a cast iron vs mod con that should be taken into account is availability of parts - make sure the boiler is well supported locally. It is also worth mentioning that the control boards and inducers on mod con boilers are typically more expensive than those on cast iron boilers so in the event of a failure the repair will be more expensive. Finally - most important aspect is a qualified installer that properly designs, installs and supports the system.
    Tinman
  • Tinman
    Tinman Member Posts: 2,808
    I can't speak for your history with mod cons but I have a number of them out there that are 12 plus years with minimal problems. Will they last another 8? I can't say for sure. Why not?

    I doubt you were referring to compressors lasting 20 plus years because that's fairly common. I've seen the old GE residential compressors last 30 years.
    Steve Minnich
  • Matt_67
    Matt_67 Member Posts: 284
    I see a comparable amount of issues with mod cons and cast iron - fairly low. It's been my experience that the mod cons tend to be more expensive to fix.
    RobG
  • RobG
    RobG Member Posts: 1,850
    Mod-Cons are coming into the technology of being (with the right equipment) easily diagnosed, just like car diagnostics. The manufacturers are not putting that technology into most cast iron boilers.

    A 67 Chevy Nova is easy to work on but will eventually only be allowed on the road as an antique collectors car. Whereas a 2015 Toyota can be hooked up to a computer and diagnosed. Technology will always prevail.

    I would rather own the Nova but I'm getting old :s
  • RobG
    RobG Member Posts: 1,850

    JStar said:

    Theoretical numbers are great and all, but I can pull out my customer's fuel bills and prove my claims.

    Interesting Joe.

    Did the customer have a brand new CI boiler with a brand new heat exchanger, perfectly matched to the heatloss with a proper system and suitable DT pumps?

    Then, of course you removed this system and installed the mod-con.

    And you have the customer's fuel bills?

    Please post them.
    Hat, is there anything that you will not argue about? If we all just bow down to you and admit that you are all knowing would it satisfy you? I used to think Icesailor was difficult, you take the cake!
    TinmanHatterasguy
  • hot_rod
    hot_rod Member Posts: 22,022
    I think the biggest unknown still is what repair cost, or parts availability will be in 5, 8 or 10 years for high efficiency equipment. Also for a homeowner, finding a qualified serviceman, or woman.

    Fact is, cast iron gas fired boilers are still a viable product and fairly easy to troubleshoot and repair. Seems the only real reliablity hassle was when they started adding vent dampers that were not engineered or designed for the task.

    Here is some actual data for boiler sales.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Tinmanj a_2Robert O'Brien
  • RobG
    RobG Member Posts: 1,850
    hot rod said:

    I think the biggest unknown still is what repair cost, or parts availability will be in 5, 8 or 10 years for high efficiency equipment. Also for a homeowner, finding a qualified serviceman, or woman.

    Fact is, cast iron gas fired boilers are still a viable product and fairly easy to troubleshoot and repair. Seems the only real reliablity hassle was when they started adding vent dampers that were not engineered or designed for the task.

    Here is some actual data for boiler sales.

    What manufacture(s) is the chart based on? I am seeing the most technology being put into the mod-cons. If you can find them, young folks will be the new technicians in the field. They will understand a computer easier than a millivolt.
  • hot_rod
    hot_rod Member Posts: 22,022
    I hope we never get to the point where service techs just "believe" the computer and are parts swappers. All HVAC service techs need to know the fundamentals, how to use a multimeter and understand 24V gas valves, able to red and understand a ladder diagram.

    Granted microprocessors are replacing the old Honeywell triple stats, but the pumps, gas valves, vent dampers need to be understood and able to be diagnosed by the service person.

    The info is from the one of the Institute that HVAC manufacturers belong to. They complied the data sent in from the members.

    Based on what the wholesalers I visit, from coast to coast tell me the mix is spot on. Tends to be more non-con iron on the shelves in the east and midwest.

    Mod cons seem to be more popular in the west, intermountain, and left coast. I always snoop when I visit suppliers to see what they inventory.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Rich_49
    Rich_49 Member Posts: 2,766
    Ja ,
    I don't know if it is an internet problem or everyone is just too sensitive but the comment was light hearted . Maybe I should put cute little emojis after all my comments so nobody knows what I'm really saying . Calm down .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833