© ⅯⅯⅩⅢ Kirby Morgan Dive Systems, Inc. All rights reserved. Document # 130115001
103
SuperLite
®
27
®
7.12.3 Overpressure Relief Valve
Reassembly
1) After cleaning, inspection and/or parts replacement,
reassemble the valve by installing the soft seat, spring,
and adjustment nut. Screw the adjustment nut down
until it is approximately 1/2 thread from being flush
with the top of the valve body.
2) Lightly lubricate a new body O-ring, then install
on the valve body.
3) Test the relief/bleed valve according to the test
procedure below.
7.12.4 Overpressure Relief Valve Lift Check/
Setting
Tools required:
Adjustable first stage SCUBA regulator or controlled
adjustable pressure source
Intermediate pressure test gauge
Torque wrench
1/2” open-end wrench adapter for torque wrench
1/8” Allen wrench
HP air source {SCUBA tank) with at least 500 p.s.i.g.
(34.4 bar).
Mild dish soap
The purpose of lift checking the relief/bleed valve is to
ensure it operates properly, allowing excess pressure to
escape in the event the first stage develops a slight leak.
Without the relief/bleed valve, high-pressure gas will
continue to increase until the emergency supply hose
ruptures, possibly causing injury and a complete loss
of the Emergency Gas System (EGS).
This procedure explains the steps necessary for readjust
-
ing the relief/bleed valve after it is cleaned, overhauled
or any time the valve is tested.
Ensure the relief/bleed
valve is only installed in
a low-pressure port of
the first stage regulator.
Installation in a high-
pressure port will lead to
loss of EGS supply and possible serious
personal injury if the valve fails.
WARNING
Do not use oxygen, or
mixed gas containing
more than 23% oxygen by
volume, for lift checking
the relief/bleed valve. The
use of oxygen, or mixed
gas, in a high-pressure
supply system not designed and cleaned
for oxygen service, can result in a fire
or explosion causing serious injury or
death.
WARNING
NOTE: The relief/bleeder valve is lift checked and/
or adjusted using an adjustable first stage regulator,
equipped with a low-pressure test gauge, which is used
for adjusting the intermediate pressure of SCUBA
regulators. The check/adjustment can be performed
using a standard SCUBA test stand, or a gas control
console, using air or mixed gas with an oxygen content
below 23% by volume.
If a first stage SCUBA regulator is used, it must be
able to be adjusted to the desired lifting pressure.
The pressure gauge should be compared to a gauge
of known accuracy.
NOTE: If the Allen screw on the relief/bleeder valve
hex nut is rotated too far, too fast, the relief/bleeder
valve will pop open. This could possibly require the
air to be secured at the cylinder or supply source to
reset the seat before the adjustment can be accom
-
plished.
NOTE: The relief/bleeder valve can be installed in
any first stage regulator, providing the first stage has
an intermediate setting of 135 - 165 p.s.i.g. (9.3 –
11.4 bar).
1) Install the relief valve in a low-pressure port on
an adjustable 1st stage regulator. Or install on the
SCUBA test stand.
2) Install the intermediate pressure gauge in one of the
low-pressure ports of the first stage regulator.
3) Install the 1st stage regulator on the cylinder. Ensure
the relief valve and intermediate pressure gauge are
attached to low-pressure ports.
4) Wet the relief valve with soapy water to help indi
-
cate gas flow
5) Slowly bring up air pressure while watching the
intermediate pressure gauge until the pressure gauge
