User Guide

Single Zone Gas Monitor
P/N: 3015-4256 Rev 10 25
3.9. The DIAGNOS Function
3.9.1. Overview
The DIAGNOS function displays sensor data and status information useful to a service technician for
troubleshooting various fault conditions. Explanations of the data shown in these screens are given
below.
3.9.2. Keypad Functions
From the Data Display screen, use the Keypad buttons to place the arrow (>) on the display next to the
DIAGNOS function. Then press ENTER to display the first of two Diagnostic screens.
Press the Up Arrow Keypad button to toggle between the First and Second Diagnostic screen.
3.9.3. First Diagnostic Screen
In the first diagnostic screen, the user can toggle between displaying the Bench Voltage / Noise and
Detector Temperature / Box Temperature by pressing the Right Arrow Keypad button.
Bench Voltage – This is the current peak-to-peak output of the IR detector. In the absence of gas this
value can range from 3.90000V to 4.50000V.
Noise – The Noise value is a 16 point running average of the noise portion of the IR detector’s output.
This reading is valuable mainly when refrigerant is NOT present.
Detector Temperature – This is the current detector temperature in °C.
Box Temperature – This is the current internal enclosure temperature in °C.
Fault Code – Current fault code. A value of <0000> indicates that no faults are being detected.
Manifold Pressure – Current manifold pressure in psia.
Purge Valve Asterisk (∗) – The purge valve can be opened and closed by pressing the Left Arrow
Keypad button. An asterisk appears on the display when the purge valve is open.
3.9.4. Second Diagnostic Screen
PPM Level – Parts Per Million Level is the current detected gas level, and is the volume concentration
referenced to standard temperature and pressure.
Average Absorption Unit – This is the optical absorbency. In the absence of gas the absorbency is
0.00000 au. When sampling selected gas, its value varies proportionally with the concentration.
µMoles/Liter – This is the absolute concentration in micro-moles per liter of gas.
Detector Voltage – This is a running average of the IR detector’s bench voltage as displayed in the First
Diagnostic screen.
Purge Valve Asterisk (∗) – When viewing the diagnostic screen, the purge valve can be opened and
closed by pressing the Left Arrow Keypad button. An asterisk appears on the display when the purge
valve is open.
4.26500v <0000>
24.5cD* 14.72psi
Bench Voltage Fault Code
Detector Temperature °C ∗ Manifold Pressure
0.00250n <0000>
29.5cB* 14.72psi
Noise Fault Code
Box Temperature °C
∗
Manifold Pressure
0.4ppm 0.00
0.00002au*4.260v
PPM Level µMole/Liter
Avg. Absorption Unit
∗
Detector Voltage