Welch Allyn Duet CO2 Module - User Manual - Manual (Page 56)

Duet CO
2
Module OEM Implementation Manual
Page 56 Confidential Welch Allyn OEM Technologies
To troubleshoot error
• Make sure that the room is well ventilated. CO
2
readings may be elevated in a closed room.
• Check that the calibration gas is of known concentration. Repeat the calibration check using a
different mainstream sensor. If the CO
2
readings are consistently elevated or depressed, the
calibration gas may be suspect. Access another gas source.
• Insure that the Mainstream sensor was warmed to the proper operating temperature of 42 o
C.
Repeat the warm up period of 15 minutes and calibration check.
• Check for the presence of a dirty or faulty airway adapter. Clean the airway adapter and repeat
the calibration check. If the CO
2
reading is still in error, replace the airway adapter and repeat
the calibration check. If different readings persist, a faulty airway adapter is suspected.
• Check for air leaks in the pneumatic tubing and connections. Repair or replace as needed.
Pneumatic System Verification (Sidestream)
Equipment includes
§ Sidestream Duet CO
2
Module
§ calibrated mass flow meter
(0 – 250 cc/min minimum range / full range accuracy 10% or better)
§ Water trap receiver assembly and Water trap
§ sample line
To perform the pneumatic validation procedure
• Insert the Water trap into the receiver assembly and connect the sample line to the Water trap
inlet.
• Connect the free end of the sample line to the vacuum side of the calibrated flow meter.
• Connect the Sidestream inlet tube to the exhaust end of the receiver assembly.
• Set the monitor to the highest flow rate i.e. 175ml/min.
• Verify that the accuracy of the flow rate reading is within the manufacturer’s specification for
the flow meter used.
• If more than one flow rate is available, repeat the above two steps for each additional flow rate.