TB 5-4220-200-12-1
e.
The 2nd stage valve (36) is "fail safe" meaning that due to its downstream design it will relieve overpres-
sure in the Intermediate pressure hose (29) if leakage of 1st stage valve (14) should occur. This IS a safety
feature.
f.
Both the 1st stage and 2nd stage regulators are "depth compensating, " because their diaphragms (20)
and (47) are always in contact with surrounding water pressure. These diaphragms sense any Increase
or decrease in ambient water pressure, causing both 1st and 2nd stage valves (14) and (36) to adjust
accordingly. This insures that air inhaled from the regulator always equals ambient water pressure regard-
less of changes in depth.
The Conshelf Arctic Explorer IS specially adapted for use in extremely cold waler due to its mainspring
g.
(23) cavity being filled with silicone fluid (28). This prevents the mainspring (23) from freezing up because
of ice forming between the spring coils. The silicone fluid IS contained inside the spring cavity by means
of a secondary diaphragm (26) capable of sensing changes in surrounding water pressure even when
the 1st stage regulator is surrounded by as much as three-quarters of an inch of ice.
h.
Removal or loosening of the diaphragm retaining ring (27) on the 1st stage regulator may result in a loss
of silicone fluid and may render the regulator unfit for frigid water usage
i.
Although the Arctic Explorer is designed for use in low temperature water, 2nd stage freeze-up and free-
flow may occur when diving in fresh water below 38F or salt water below 35F if the regulator IS purged
for longer than five seconds. This freeze and resultant free-flow is due to ice forming around the demand
valve lever (39). If this condition is encountered, it is necessary to remove the regulator from the mouth.
allowing water to enter the mouthpiece (55) to dissolve the ice deposits.
Also, in intensely cold surface temperatures while the regulator IS idle between dives, it should be kept
j.
in a dry location above 32F to eliminate the possibility of ice forming in the 2nd stage demand mecha-
nism.
TWIN CYLINDER VALVE MANIFOLD.
2-3
a.
General. The basic function of the twin cylinder reserve valve is an ON OFF valve to control the air sup-
plied from two diving cylinders, combined with an air reserve mechanism that begins restricting air flow
at approximately 600 psig and shuts off flow at 500 psig. This warns a preoccupied diver that he IS low
on air. He then actuates the reserve lever to breath the remaining air in his cylinder.
b.
ON/OFF Valve. The ON/OFF valve is in the center and IS used to control the air supply from both cylinders.
The ON/OFF valve mechanism consists of a nylon seat-disc in a metal retainer which screws down
against a metal seat to shut off cylinder air. Turning the ON/OFF knob clockwise until finger tight shuts
off cylinder air.
Never turn the knob more than finger tight as this will damage the disc in time. To
open the valve, turn counterclockwise approximately two turns or less until it
stops. (Never try to force it beyond this point.) Then turn valve clockwise from 1/4
to 1/2 turn and stop.
c.
Constant Reserve. The constant reserve is located on the diver's left cylinder. It allows a predetermined
volume of air to remain entrapped in the left cylinder, while the right cylinder is breathed empty. When the
reserve lever is pulled DOWN air is allowed to flow into the empty cylinder until pressure in both cylinders
equalize.
d.
Elbow Assembly (Tank Block P/N 0638). The elbow assembly has no moving parts. Its function is merely
a threaded connector between the right cylinder and ON/OFF valve.
e.
Use. Allow a short burst of air to clean out the filling port prior to attaching a regulator to the twin manifold.
After the regulator is attached. open the ON/OFF valve and set the reserve lever in the "UP POSITION"
for start of dive.
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