Ohmeda 3000 - Pneumatic Troubleshocting

5/Disassembly and Repair
2. Remove the eight mounting screws for the Oxy-
gen Yoke and Regulator Assembly and then re-
move the assembly. .
Disconnect the copper tubing from the outlet
port of the regulator and the elbow of the man-
ifold port.
Remove the regulator from the manifold block
by tuning it counterclockwise.
. Place the regulator in a vise with the spring
case up.
. Turn the adjustment screw counterclockwise
until the screw no longer exerts pressure on the
internal parts of the regulator.
. Use a 1 1/2 inch wrench on the hexagon of the
spring case, and unscrew it by turning it coun-
11.
12.
13.
14.
15.
terclockwise.
8. Remove the spring case, spring button, spring,
diaphragm plate, diaphragm and thrust plate. 16.
9. Using a wrench, remove the seat retainer, о-
ring, pin, seat, valve assembly, and marginal 17.
spring.
18.
10.
Replace new pin, o-ring, seat and marginal
spring with parts from repair kit No. 0306-9951-
870.
G. Pneumatic Troubleshooting
20.
This troubleshooting information provides a list of
some problem conditions, possible causes, and solu-
tions. If any of the below symptoms occur, shut off
the oxygen cylinder valve.
Condition
Gas leakage at the
regulator outlet
when the adjustment
screw is completely
released.
Outlet pressure in-
creases steadily
above set pressure
{no flow through
system).
Gas leakage from the
spring case.
Excessive drop in
working pressure.
Gas leakage from
relief valve.
5-20
Possible Cause
Leak across the
regulator seat.
Leak across the
regulator seat.
Loose spring case or
damaged diaphragm.
Worn or sticking in-
ternal parts. Internal
flow obstructed. Dirty
filter. Cylinder valve
not fully open. Dirty
yoke check valve
strainer nipple.
Dirty valve seat.
Leak across the
regulator seat.
19.
Use a wrench to tighten the seat retainer into
the regulator body to a torque of approximately
119 inch pounds.
Replace thrust plate diaphragm, diaphragm
plate, spring, spring button and spring case.
Use a wrench across the hexagon on the spring
case, turn the case clockwise to replace it. Do
not over-tighten.
Reattach the regulator to the manifold block.
Use Teflon tape to seal the thread connection.
Note: The regulator must be reset to 52 + 2
psig with a 500 cc flow passing through it.
Attach the special fitting and gauge assembly
{Tool Number 0175-0543-000) to the regulator
outlet. This special tool has a (0.025 in.) orifice
to maintain a 500 cc flow for proper regulator
adjustment.
Adjust the regulator adjustment screw until the
pressure gauge reads 52 + 2 psig.
Tighten the adjustment screw lock nut.
Remove the special fitting and gauge assembly.
Reconnect the copper tubing to the regulator
outlet.
Place the assembly in position and replace the
eight mounting screws.
Solution
Replace seat and
corresponding parts.
Replace seat and
corresponding parts.
Check seating of
spring case. Replace
diaphragm if damaged.
Replace worn or stick-
ing parts. Check for
flow obstructions.
Replace filter. Open
cylinder valve. Clean
yoke check valve and
strainer nipple.
Replace seat and
corresponding parts.