Upon arrival customer stated they saw some smoke/soot coming from the baseboard heaters. What they saw was just dust buildup getting heated up by the baseboards warming up and is typically more common at the beginning of the season. The baseboards cannot make smoke or soot. Customer asked us if we could perform a maintenance on the natural gas boiler Performed pm on natural gas boiler Brushed and vacuumed burner tubes Cleaned and inspected flame sensor Inspected and vacuumed burner compartment and surrounding area Checked electrical connections and safeties Checked gas pressure Performed combustion test Inlet pressure-8.158 in.w.c. Manifold pressure- started at 3.6 adjusted it to 2.696 in.w.c. To make to unit run clean 7.3%o2 12ppm co