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Laars mini therm soot

Elpisador
Elpisador Member Posts: 1
I have a Laars mini therm jvs125boiler about 10 years old. Had to clean soot 3 times over the last winter. Unit cycles on-off after a few seconds of firing up. Sometimes I get a buzzing sound. Any help is greatly appreciated. Thanks in advance. 

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 24,731
    Combustion is off. Get a competent tech. in there to thoroughly clean it, and with the proper test instruments and get everything set as it should be for best combustion. It is impossible to set a burner correctly by eye or by ear.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    kcoppSTEAM DOCTOR
  • hot_rod
    hot_rod Member Posts: 23,271
    Short cycling and low return water temperature are a couple causes of copper tube boilers sooting up.

    Things get worse as the fins plug up.

    Get a CO meter near that beast.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,400
    Yes, HX probably plugged with soot.
  • HomerJSmith
    HomerJSmith Member Posts: 2,635
    How's your combustion air?