AirSep MN138-1 H - Manual (Page 32)

26
MN138-1 Rev H
02/14
5.0 Troubleshooting
5.1 Operating Pressure Test
Testing the operating pressure is a useful diagnostic tool when a concentrator has low oxygen
concentration and requires servicing. Units functioning normally do not require operating tests.
Use the following procedure to test the operating pressure of the unit:
1.
Set the unit’s I /0 power switch to the “0” position, and unplug the power cord.
2. Remove the front panel of unit.
3. Locate the pressure test port location (black tube located on the top right side between the
compressor enclosure and center section). Using a pressure test adapter (AirSep p/n: KI257-
2), connect the pressure gauge to the test port.
4. Plug in the power cord, and set the unit’s I /0 power switch to the “ I ” position.
5. Set the flowmeter to the maximum flow rate for the unit and allow it to run five minutes.
6. Observe the maximum and minimum readings on the pressure test gauge.
The maximum reading should not exceed:
VisionAire:
30 psig (207 kPa)
VisionAire 2: 25 psig (172 kPa)
VisionAire 3: 25 psig (172 kPa)
The minimum reading should not be less than:
VisionAire:
8 psig (55 kPa)
VisionAire 2 7 psig (48kPa)
VisionAire 3: 7 psig (48kPa)
When you turn the unit on, the system pressure always registers higher than
normal for the first few minutes of operation.
5.1.1 High Operating Pressure
Higher than normal operating pressure may indicate any of the following:
• A restrictive exhaust muffler, which does not allow the waste (purge) gas to exit the
system freely. Operate the unit with the exhaust muffler disconnected to see if the
operating pressure returns to normal.
• An improperly operating circuit board or solenoid valve.
Confirm that the circuit board and solenoid valve function properly.
• Contaminated sieve beds.
Change the sieve beds.
5.1.2 Low Operating Pressure
If the oxygen concentration level at the desired liter flow is within AirSep’s specifications, no
service is required, even if operating pressure is low. If concentration is below specifications at
the desired liter flow rate with low operating pressure, this may indicate any of the following:
• A restriction in the compressor intake path may be limiting the amount of room air
available to the compressor.