User Guide
55
Service Manual NeoTherm 80 - NeoTherm 285
2. Once you have completed the high re combustion test, measure the CO
2
/
O
2
in the ue products at Low Fire.
How to get there: Use the Down arrow to set the “Rate” to “20%.” The NT
unit is now forced to low re mode for 5 minutes.
The CO
2
readings should be between the values shown in Table C2-1. If
the CO
2
is not within the range shown, adjustments may be made. To adjust
the low re CO
2
, locate the low re adjuster screw as shown in Fig. C2-1.
Slowly make adjustments in 1/16 of a revolution increments until the CO
2
is within the range identied. For the low re adjustment, turning the screw
clockwise (CW) opens the adjustment and makes the mixture richer.
3. Repeat steps 2 and 3 to conrm that the CO
2
readings are within the re-
quired ranges. Adjust each setting again if necessary.
4. Conrm that the differential pressure is still within the appropriate range.
5. If any of the measurements cannot be adjusted to the specied ranges or
the CO levels are above 150 ppm when adjusted, see Section C4, “Trouble-
shooting Combustion Problems.”
6. Remove the differential pressure gauge from the air and gas pressure taps
making sure to close all ports after the gauge has been removed.
Combustion Adjustment Procedure -
Units with Original (White) User Interface - continued
C2
cont.