(c) Replace the disc. The new gas evacuator/relief valve disc and
diaphragm are one piece, not two separate components.
(d) Replace the spring sleeve.
(e) Replace the spring.
Replace the pin.
(g) Replace the knob.
(h) Replace the O-ring.
Replace the face plate (mount the face plate cap with warning label
Replace the four screws.
Do not obstruct the air vent in the knob of the valve. This vent helps
prevent a pump action from developing in the spring sleeve when gas is
flowing past the diaphragm. If the valve begins to chatter or vibrate,
lubricate the outside of the spring sleeve with a light film of Vac Kote.
(5) Ensure that the breathing circuit pressure gauge reads zero. If the
pressure gauge does not read zero, re-zero it.
(6) Determine if the gas evacuation/relief valve relieves pressure at
2.5 mm Hg or less.
(a) Turn the knob fully counterclockwise. Force the gas out through
the valve by slowly squeezing the re-breathing bag.
(b) Note the reading on the absorber pressure gauge.
(7) If it relieves pressure at a pressure higher than 2.5 mm Hg when set to
the minimum pressure relief setting, determine if you properly reassembled the valve or
if the spring is stretched out.
(a) If you reassembled the valve improperly, reassemble it and conduct
all checks again.
(b) If the spring is stretched out, replace it.
(8) Ensure the gas evacuator/relief valve is not used until the valve has
been repaired and retested.