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Gas Boiler Recommendation

GidaGida Posts: 5Member
Hi All, My 22-yo Weil/Mclein WGO-3 boiler cracked (I have 3-Zone baseboard (In BR's) & Quiet-one Kick space heaters (KS-2004) in LR/Kitchen in house) with a Weil Mclain indirect Gold 40 Gal-DHW heater. I figure it's a good time to switch to gas from oil and install a Viessman Vitrocrossal CU3A or Weil McLain GV 90 (or similar). Current system is on a Tjerlund SS2 power venter (so getting rid of this is a big motivation along with payback of gas). Also, I might put in radiant under joist flooring in the future (living room). Appreciate any thoughts, Rhode Island


  • HenryHenry Posts: 872Member
    Simple HTP UFT or FT depending on the house size
  • newagedawnnewagedawn Posts: 549Member
    im a huge peerless fan, there made in USA, in boyertown ,pa and are very efficient boilers for gas or oil
    "The bitter taste of a poor install lasts far longer than the JOY of the lowest price"
  • HVACNUTHVACNUT Posts: 1,911Member
    > @newagedawn said:
    > im a huge peerless fan, there made in USA, in boyertown ,pa and are very efficient boilers for gas or oil

    The WBV and ECT are good boilers. The Purefire modcon, no so much IMO.
  • lchmblchmb Posts: 2,895Member
    I've installed a lot of the GV-90..nice quiet little boiler. I've installed 20 to 30 so far..
  • unclejohnunclejohn Posts: 1,356Member
    edited June 2018
    Since you have all baseboard and will most likely run a 170*F supply I would go with a standard cast iron. Buderas makes a good non condensing boiler. I like the Logano models. The Logano is 85% eff. Compare the price of the install with the WM GV90 which by the way is not a mod. con.
  • HenryHenry Posts: 872Member
    One does not run at 170F all winter. Here out 1100 hours of boiler operation, there is between 100 to 200 hours at design temperature. A condensing boiler with Outdoor Rest is the way to save energy.
  • GidaGida Posts: 5Member
    Watch the Viessmann Vitocrossal webinar. It is designed for 194-deg temperatures (although less efficient when running high return), it'll still be more efficient than a cast iron conventional boiler.
  • DC123DC123 Posts: 69Member
    FWIW, I had a CU3A installed about 1.5 years ago and have been impressed with it so far. Very quiet esp since only one pump is needed (no primary secondary).
  • ZmanZman Posts: 4,694Member
    Gida said:

    Watch the Viessmann Vitocrossal webinar. It is designed for 194-deg temperatures (although less efficient when running high return), it'll still be more efficient than a cast iron conventional boiler.

    Viessmann has for years pushed the low mass water tube design while others (like Triangle tube and Lochinvar) have pointed out the advantages of the high mass fire tube. In this training (sales) video, they act like they just thought of the idea of high mass boilers.

    A few thoughts:
    No mod con boiler runs high efficiency at high return water temps. If high temp is what you want, just buy a conventional boiler. A properly sized 2 stage conventional boiler will perform as well as the Viessmann or any Mod/con in a high temp environment with much lower install and maintenance costs. If your system is microzoned, add a buffer tank to eliminate cycling.

    You home would probably heat well most of the year at lower return temps. If you do a room by room heat loss at design and typical outdoor temps and compare those numbers to radiators installed, you can estimate this.

    If you go the condensing route, take a look at the Lochinvar WHN series. Not quite as much mass, but with a 10-1 turndown, lower price tag and simpler design, it is hard to beat.

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • heidlemlheidleml Posts: 14Member
    I second the Lochinvar route...I have installed quite a few Noble Combi boilers and they have been easy to install, intuitive interface and no problems thus far. I have also used TT and WM combi units and have not been as pleased.
    Also, all of these products are designed to fail after a certain time...I'd much rather be swapping out a wall mount combi than 80 gallon storage tank.
    Combi units by nature do have limitations on flow rate so you will have to take that into consideration.
  • GBartGBart Posts: 753Member
    Bear in mind that it isn't a given that switching to gas WILL save you money,

    The prices of gas and oil go up and down, gas and LP usually go together because they are both products of crude, natural gas usually goes the opposite because they try to lure people in for a switch when oil is high then it goes up.

    Gas has an advantage now with variable speed or modulating equipment because oil can't do this, but you need to buy a unit capable of this to reap the benefits. So if your home requires 85,000 btu/hr you would want a unit capable of modulating between 20- 85-100,000 btu/hr, this way when one zone is calling or it's a warm day the unit will ramp down and match your current load requirements instead of running at full throttle all the time.

    I also like the Weil McLain Ultra series-

    Please do a load calculation to ensure you are installing the correct size boiler, 9 times out of ten your current boiler is WAY over sized and you will save more with the correct size, this is an easy use program.
  • SuperJSuperJ Posts: 466Member
    The CU3A is different than other high(medium) mass fire tubes in that it has no minimum flow requirement. Most of the firetube wall hung boilers require some flow, which means a P/S arrangement and maybe a buffer if microzoned at all.

    If I had the budget for a CU3A it's the only boiler I would consider. There's a lot to like about it besides the high mass aspect. To me it seems like it might be one of the few 20year capable modcons.
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