AirSep MN118-1 B - Manual (Page 25)

MN118-1 rev B
02/14
20
6.0 Troubleshooting
6.1 Operating Pressure Test
Testing the operating pressure is a useful diagnostic tool when a concentrator produces low
oxygen concentration and requires servicing. Units functioning normally do not require
operating pressure 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 disconnect the power cord.
2. Remove the right side panel.
3. Locate the pressure test port location (black tube with plug in the end). Remove
plug, and using a pressure test port adapter (AirSep p/n KI257-1), connect the
pressure gauge to the test port.
4. Connect the unit to power, and set the unit’s I /0 power switch to the “ I ” position.
Set the flowmeter to 8 lpm, and allow the unit to run five minutes.
5. Observe the maximum and minimum readings on the pressure test gauge.
The maximum reading should not exceed 34 psig (234 kPa).
The minimum reading should not be less than 10 psig (69 kPa).
When you turn the unit on, the system pressure always registers
higher than normal for the first few minutes of operation.
6.1.1 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 valves function properly.
• Contaminated sieve beds.
Change the sieve beds.
6.1.2 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 intake resonator, which limits the amount of room air
available to the compressor.
Disconnect the braided tube at the compressor, and allow the unit to operate
without the intake resonator to see if normal operating pressure returns.
• A compressor with reduced output.
If it is below specifications, replace or repair the compressor.
• An improperly operating circuit board or solenoid valve.
Confirm that the circuit board and solenoid valves function properly.
• A leak in the unit, which allows system pressure to escape.
Leak test unit.