Servicing
Reaction Chamber Cleaning or Removal
7-20
Model 42
i
Trace Level Instruction Manual
Thermo Fisher Scientific
2.
Set the NO BKG and NO
x
BKG calibration factors to 0.0. Refer to
“Calibration Factors Menu” in the “
Operation
” chapter.
3.
Set the NO COEF, NO
x
COEF, and NO
2
COEF to 1.000.
4.
Set the Averaging Time to 10 seconds. Refer to “Averaging Time” in
the “
Operation
” chapter.
5.
Connect the calibration gas and allow the instrument to sample
calibration gas until the reading stabilizes.
6.
From the Main Menu, press
to scroll to Service > press
>
to scroll to
PMT Voltage Adjustment
> and press
.
The Set PMT Voltage screen appears.
Note
If Service Mode is not displayed, refer to “Accessing the Service
Mode” on page , then return to the beginning of this step.
▲
7.
At the Set PMT Voltage screen, use
to
increment/decrement the counts until the instrument displays the
calibration gas concentration value.
Use the following procedure to clean or remove the reaction chamber (see
Figure 7–10
).
Equipment Required:
Allen Wrench, 9/64-inch
Wrench, 7/16-inch
Wrench, 9/16-inch
Equipment Damage
Some internal components can be damaged by small
amounts of static electricity. A properly grounded antistatic wrist strap
must be worn while handling any internal component.
▲
1.
Remove PMT cooler as described in “PMT Cooler and Reaction
Chamber Replacement” in this chapter.
2.
Disconnect all plumbing connections from the reaction chamber.
Reaction Chamber
Cleaning or Removal
