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Cleaning a Laars boiler.

We have many Laars boilers out here on the West Coast and they often soot up on radiant systems with low return water temperatures. Cleaning them is a dirty job, but it will return a boiler to working condition.

This particular Laars has a setpoint of 160F and wasn't that dirty, but there was something going on as the flame rollout switch had been bypassed. The shopvac was all we had to use to clean the fins on the HX. On more stubborn ones, we have to use high pressure water to clean it properly.

Most of these pictures were taken after the cleaning was done.

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


    EBEBRATT-Ed Member Posts: 15,616
    Those are fun. I have cleaned a few Larrs & Raypaks. We don't have that many around here. Popular for pool heating though
  • kcopp
    kcopp Member Posts: 4,441
    edited January 2019
    There are a fair number around here in NH as there is a factory in Rochester. For the most part a good shop vac , wire brush and a respirator they clean up well. At least yours is up off the floor. around here they plant them either directly on the floor or maybe a 1" patio block... :s