AirSep MN138-1 H - Manual (Page 25)

19
MN138-1 Rev H
02/14
When the lockout adjustment is no longer required, follow the normal
regulator setting procedure as described in Section 4.8.1.
4.8.3 Back Pressure Correction at Maximum Flow Rate
In some cases, additional lengths of oxygen tubing with a humidifier bottle can increase
back pressure and limit oxygen flow below the maximum flow setting.
To achieve full maximum flow setting, use the following procedure:
1. Plug in the unit.
2. Set the unit’s
I /0 power switch to the “ I ” position, and allow the unit to run five
minutes to build up pressure.
3. Connect the humidifier bottle, oxygen tubing, and cannula to the oxygen outlet.
4. Turn the flowmeter adjustment knob counterclockwise until the ball reaches the stop
at the top of the flow meter (wide open).
5. Remove the back panel of unit.
6. Pull outward on the regulator knob to unlock it.
7. Turn the regulator knob clockwise until flow meter ball is set
½ liter above the
maximum flow rate .
8. Push in the regulator knob to lock the setting.
9. Turn the flowmeter adjustment knob clockwise until the flowmeter indicates
maximum flowrate.
10. Reconnect back panel.
When this back pressure correction is no longer required, follow the
normal regulator setting procedure as described in Section 4.8.1.
4.8.4 Product Regulator Cleaning or Rebuilding
Clean or rebuild the product regulator if the flow meter ball fluctuates more than ¼ liter
or if the regulator cannot be adjusted for lockout.
1. Set the unit’s I /0 switch to the “0” position and unplug the power cord.
2. Remove the back panel.
3. Use large pliers to unscrew the bonnet of the product regulator, which contains a
large spring.
Adjust the product regulator fully counterclockwise to unload the spring.
This makes disassembly and reassembly easier.
4. Remove the diaphragm. (Clean or replace it.)
5. Using a Phillips-head screwdriver, unscrew the diaphragm stem guide located in
the center of the regulator body to gain access to the seat.
6. Remove the seat. Be careful not to lose the spring located behind the seat.
7. Clean or replace the seat.