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Boiler opinion wanted: Laars Mini-Therm

JohnNY
JohnNY Member Posts: 3,226
Hello all,
I'm soliciting opinions on this Laars Mini-Therm boiler. I like the idea of having my guys easily carry 200,000 BTUs down rickety old Brooklyn cellar steps rather than risk injury with a 500-pound piece of cast iron as they have for decades.
https://s3.amazonaws.com/s3.supplyhouse.com/product_files/Laars-JX200NLIU1-Brochure.pdf
Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
Consulting & Troubleshooting
Heating in NYC or NJ.
Classes

Comments

  • JUGHNE
    JUGHNE Member Posts: 11,042
    One would think they would have included the shipping weights in the spec sheet.
    Certainly less than standard CI.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453


    Flow I think is the key to keeping them happy. Primary Secondary. They get a lot of use in pool heaters etc.

    I bet @Alan (California Radiant) Forbes see's a lot of these
    Alan (California Radiant) ForbesJohnNY
  • jad3675
    jad3675 Member Posts: 127
    JUGHNE said:

    One would think they would have included the shipping weights in the spec sheet.
    Certainly less than standard CI.

    supplyhouse.com has the weight listed on the product page - the 100K unit is 145lbs.

    John
    JUGHNE
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,513
    What Ed said about proper flow rate. They work best on primary/secondary. Year ago, I did some work for them. I asked their engineers if they ever considered making a steam boiler. He said they had one now. "All you have to do is use the wrong pump," he said.

    Pipe it right (as I know you will) and I think you'll like these a lot. And your point about the rickety Brooklyn stairs would sure be my convincer.
    Retired and loving it.
  • hot_rod
    hot_rod Member Posts: 22,022
    I would add that they like a consistent load as they are usually a fixed output. Some models had two stage gas valves.
    On a multi zoned system, especially with micro zones a buffer may be desired.
    They need boiler return protection if used on low temperature radiant.

    Hard to beat copper as a heat exchange material, these have a long proven history and are fairly bulletproof even in abused installations :) These and other copper tube brands were the go to in the early radiant days.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Agree with all the above. I service about 200 or more of them here in the Bay Area; their JVS Mini-Therms were very popular in the 80's and 90's and are still going strong; almost indestructible. They will soot up when they serve radiant unprotected, so 1°-2° piping is in order.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • BigRob
    BigRob Member Posts: 322
    The delta T pump across the low loss header is cool. The literature mentions adjustable water temperature and outdoor reset. I guess the control PWM's the gas valve?
  • JohnNY
    JohnNY Member Posts: 3,226


    Pipe it right (as I know you will) and I think you'll like these a lot. And your point about the rickety Brooklyn stairs would sure be my convincer.

    Thanks, Dan. Every time we lug a cast iron hot water boiler into a house I shake my head and wonder how long we're going to do this for.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
    Classes