Venturi Replacement Kit
for PRESTIGE 399
Date: 5/30/12
2011-52 Venturi Repl. Kit Prestige 399
5. Press the
RIGHT
button to adjust the firing rate
to 100%. Hold down the
RIGHT
button to
rapidly increase the firing rate.
6. If the combustion levels during High fire are
outside the recommended combustion settings
adjust the THROTTLE SCREW (see Fig. 4) as
follows:
Counter-clockwise adjustment of the THROT-
TLE SCREW at high fire:
O2 decreases and C02 increases
Clockwise adjustment of the THROTTLE
SCREW at high fire:
O2 increases and CO2 decreases
7. Once the combustion level is set at High fire,
manually place the boiler into Low fire mode by
pressing the
LEFT
button to adjust firing rate
down to 0%.
8. If the combustion level during Low fire is not
within +/-0.2% of the combustion level mea-
sured at High fire, adjust the OFFSET SCREW
below the cap on the gas valve (see Fig. 4) as
follows:
Counter-clockwise adjustment of OFFSET
SCREW at low fire:
O2 increases and CO2 decreases
Clockwise adjustment of OFFSET SCREW at
low fire:
O2 decreases and CO2 increases
9. Press the
OK
button while the fan icon is high-
lighted to shutdown the burner.
10. Press the
LEFT
or
RIGHT
button to highlight
the home screen icon
to exit the service
mode.
