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Weil McLain ultra 155

Snowmelt
Snowmelt Member Posts: 1,415
Went to a job, more like an abortion, machine goes into a soft lock out on high temp.
The question is will undersized primary piping do this. Personally I think so on this job so he lowers the supply temp to 150 degrees

Comments

  • hot_rod
    hot_rod Member Posts: 22,120
    If it has worked in the past?  How old is it? A plugged boiler is not uncommon with those aluminum blocks
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Snowmelt
    Snowmelt Member Posts: 1,415
    He keeps the temp low ……, I think it’s 5 years old, as soon as he sets it to 160 it goes off, I think from day 1
  • hot_rod
    hot_rod Member Posts: 22,120
    The installation manual should indicate the minimum flow it needs. The pump and pipe needs to be able to move that many gpm. Is it piped P/S?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Tim_D
    Tim_D Member Posts: 128
    If its going off on high limit it is not a dirty HX. A dirty HX would go off on high stack temp without transferring energy to the water. I would suspect that someone has set the high limit (boiler settings) too low. Set the high limit to 200 and the operating limit to your desired temperature. If that is all good it is a flow issue.
  • Snowmelt
    Snowmelt Member Posts: 1,415
    I was supposed to go yesterday to look at it, it still works. He keeps the temp low on the boiler