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Best Gas Boiler for me

allyg Member Posts: 6

I am looking to convert my existing oil boiler to a gas boiler. At the same time we are thinking we should replace our water heater, as it is over 20 years old.

I am exploring our options and there are a lot of different products that we could go with. I won't deny it. I want the most reliable and the longest lasting, most efficient product we can purchase.

I'm thinking Viessmann but I've also heard good things about Alpine.

Do we get a combi solution or keep them separate?

My space is about 2000 square feet finished and 3000 square feet unfinished. I have two different lines for two floors.



  • Paul48
    Paul48 Member Posts: 4,469
    So........You're planning on doing this next spring? That way you have plenty of time to educate yourself and weigh your options. It depends on how "involved" you want to be. I'm a homeowner, like you and there's some guys here that I would trust completely.
  • There is a dichotomy that isn't discussed often enough in our business, and that is between the efficiency gains in ultra high efficiency equipment, and the cost to install and maintain that equipment.

    Two questions will illustrate the point:

    1. What income class of people would benefit most from conserving the most energy?
    2. What income class of people is the most likely to purchase ultra high efficiency equipment?

    The average homeowner stays in their home 13 years. What's the payback period (not talking commercial here!) before the increased savings pay for the increased expense? And what about the complications when service is required? No one talks about that.

    There is a market distortion going on that it causing this. Every month millions of gas customers are paying an extra charge on their bills to promote this type of equipment. Just like wind and solar, with incentives there's a market. But without?

    I like keeping it simple. You'll save the most money by far if you keep your existing boiler, but have your preferred contractor and replacement boiler roughly choosen and spec'd. One day it will fail and you'll be ready to go when it does. Until then, count the savings. No boiler is so efficient that it can outperform a boiler already paid for. Take a cruise.

    As to reliability, there's nothing that can go wrong with your current boiler (or any replacement oil boiler) that cannot be immediately fixed with parts already on any half-way qualified oil company van. Doesn't get more reliable.

    Price of oil in the future? Same as the price of gold, silver, corn, or Hillary's cattle futures. No one knows. You can't plan for that.
    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
  • Steamhead
    Steamhead Member Posts: 16,832
    What boiler do you have now? Make and model?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Chester
    Chester Member Posts: 83
    Allyg: If you want to do it right, it's premature to focus on the 'best' brand of equipment, at least based on the info you've provided. The equipment you use for heat and hot water is a system that needs to be designed and installed based on your specific needs, wants and various on-site conditions. The best place to start is to find a qualified local installer. There are lots of good manufacturers out there but the design and installation is just as important if not more important than the company that makes the boiler.

    All we know is that you have a 2,000 sq ft house and it sounds like you have two zones. Some of the additional considerations include:

    Is it a steam or hot water system?

    If it's forced hot water do you have radiators or baseboard (or something else)?

    Is the existing boiler in decent shape and you're just looking to convert it to gas? Or do you really need a new system because there's a puddle of water on the floor?

    For a new system, how big a boiler do you need? This is determined by having someone do a 'heat loss' calculation which takes into account how well insulated your house is and whether you live in New Jersey or northern New England. Sizing the boiler correctly is very important.

    For domestic hot water (DHW) are you meeting the needs of a large family with teenagers or just yourself? Also, my impression (I'm just a homeowner) is that, while combi boilers are very popular, there's often a tradeoff because if you size them for your hot water demand it might not be the optimal size for your heating load.

    It's important to consider venting. A modulating/condensing boiler (ModCon) is usually but not always vented directly through a side wall. It's relatively inexpensive but creates a cloud of steam during cold weather that can be an aesthetic consideration. If you go up through an existing chimney, a ModCon requires a specialized liner (per manufacturer's specifications) that can be a significant cost element. For a more traditional high-mass boiler you may or may not need to reline your chimney depending on what's already there.

    You also need to consider what to do with your existing oil tank. If you want to have it removed that's a cost element.

    Hatterasguy makes a really important point: ModCons only deliver their rated efficiency (and, therefore, make economic sense) if you are willing and able to tune them properly to ensure low return water temperatures. Otherwise you're going to get the same efficiency with an appropriately-sized high-mass boiler that will probably be cheaper and, possibly, longer-lasting/more reliable.

    Are there any state or utility rebates or tax incentives that might affect your decision?

    Do you just want to 'set it and forget it' or are you the kind of person that's able and willing to dig into the manual and figure out how to adjust the settings? If you get a ModCon the factory defaults will probably work but won't ensure optimal performance, and you can't expect your installer to make a bunch of house calls for free until you get it dialed in.

    As you can see, there are lots of considerations. A good place to start is by getting recommendations and talking to a couple highly-regarded local contractors. Then come back here and get the Board's reaction to what they're telling you :-)

    delta T
  • allyg
    allyg Member Posts: 6
    edited October 2016
    Hello everyone,

    Thanks for your replies and I've taken some time to get additional estimates and can provide more specific answers to the questions put forth here.

    We have a hot water system with forced hot water baseboards. The existing boiler is not in good shape, it is 30 years old and need to be replaced and moved to an exterior wall so we can stop using our chimney. We also live in the Northeast US.

    Also our hot water tank is from the late 90s, so we've also asked for estimates on hot water tank replacements or combi units.

    Here are the quotes I've received for different products:

    Option A: Bosch Green Star 100 gas fired modulating hot water condensing boiler with an efficiency rating of 95% (modeL # KBR28-3)
    Crown Mega store 40 gallon stainless steel indirect hot water tank that comes with a limited lifetime warranty.
    Warranty: The boiler comes with a limited lifetime warranty on the heat exchanger and also comes with a six year parts and labor warranty which will eliminate the need for you to purchase a yearly service policy.

    Option B: Viessmann Vitoden 200/35 95% efficient boiler (B2HB35)
    40-gallon stainless steel lifetime warranty SSU-45 indirect

    Option C: Viessmann 222F boiler with integral 26-gallon tank eliminating SSU-45

    Both B & C also provided:
    Option to upgrade to variable speed ECM pumps to conserve energy add
    Option to install 11/4 dirt magnet on return

    Both boilers are limited lifetime warranty on heat exchangers and lifetime on water tanks and 10yr on other non-maintenance items IE circulators and igniters these are normal maintenance items. Parts warranty are boiler parts only.


    Warranty: 5-year part replacement warranty

    I have trimmed down my list to these 4 installations and I'm either leaning towards the Viessmann combi or the Bosch, but honestly I'm not an expert and it is frustrating because every estimate I've gotten has been for a different product with a different opinion. I'd love to hear any and all suggestions on what you would do and how I should move forward.

    Thanks again, Ally

  • KC_Jones
    KC_Jones Member Posts: 5,737
    We don't discuss pricing on this site, it would be good if you edit your post to remove all pricing information.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • allyg
    allyg Member Posts: 6
    Sorry about that and pricing has been removed.
    Erin Holohan Haskell
  • KC_Jones
    KC_Jones Member Posts: 5,737
    What is the heated square feet of this home? You mention 2000 and 3000 that totals 5000, but how much of that is actually heated? Did any of the installers talk about doing a building heat loss calculation to confirm final boiler sizing? The heat loss is the only way to properly size the boiler.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • allyg
    allyg Member Posts: 6
    Hi, we have a total of 2000 square footage finished, and then 1000 unfinished. I should have never mentioned 3000 :(

    None of the 8 installers I had visit mentioned doing a heat loss calculation. Can you point me to some information on how I can do this?
  • KC_Jones
    KC_Jones Member Posts: 5,737
    allyg said:

    Hi, we have a total of 2000 square footage finished, and then 1000 unfinished. I should have never mentioned 3000 :(

    None of the 8 installers I had visit mentioned doing a heat loss calculation. Can you point me to some information on how I can do this?

    Not surprising, if I was to take a wild guess you probably only need a boiler less than half the size they are recommending. Slant fin has an app you can download to do your own heat loss calculations for reference.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • allyg
    allyg Member Posts: 6
    After reviewing some other posts I am seeing that a heat loss calculation isn't as easy as I hoped. I'll have to spend some time doing the calculations myself. I also reached out to the one installer on this site that is local to me.

    Do you have a particular brand that you'd suggest or recommend over another?

  • Sailah
    Sailah Member Posts: 826

    As a point of reference, I have a large older home in MA and recently went through getting my heating systems (I have 3...) upgraded.

    Of the 3 contractors who came out to do quotes, 2 of them showed up at my home with a schematic of my house and took what measurements they needed to do a Manual J heat load calc.

    One heating system is relatively new (i have forced hot air) and staying put. The other 2 furnaces totalling 235k BTU were downgraded to a single 60k BTU furnace. The contractor shared his heat load calcs with me and stood by his numbers. He also came highly recommended.

    He took the time to measure all my windows, spent time discussing why my return registers needed to be modified etc. He measured, discussed what I wanted and then sized the equipment based of that, not just looking at the nameplate on the furnaces.

    Prior to this I went through a major insulation project and really tightened things up as best as I could in an 1815 home.

    I spent a lot of time researching the various options myself so I knew what questions to ask, but I also let the contractors explain what they would do. I had lots of questions and felt it was helpful going through the exercise.

    Even though I'm in the HVAC business I admit knowing probably just a little more than regular homeowner, perhaps less. To me, having a real pro do the work is much more important to me than "the best" equipment. I think all the manufacturers make good equipment (although I think mine is the best o:) , what makes the difference is it the right equipment for you, your house, and your budget. I could tell that the contractors who would take pride in their work were the ones willing to spend the extra time with me in the beginning, not just rush through with a quote.
    Peter Owens
  • allyg
    allyg Member Posts: 6
    Hi Peter!

    I also live in MA and are you able to recommend a specific contractor in the NorthEast area?

    Thanks again!
  • John Mills_5
    John Mills_5 Member Posts: 951
    I recall a house we did years ago. In floor radiation, rare here. 2 relic boilers totaling 550,000 BTU. Replaced with 1 cast iron 175,000 BTU properly piped thanks to help from an expert. Customer said bills dropped like a rock and house was never so comfortable. Bigger is not better.