Installation; Operation - Point Four Systems MBD075 User Manual

INSTALLATION

To avoid bubble coalescence, place the
diffuser horizontally and do not obstruct
the surface with protective screens. The
deeper the diffuser is placed in the water
the more effective it will be. Secure
diffuser to a flat surface using "Velcro"
strips, silicone or screws. Do not over
tighten. Use ¼" (6 mm) ID hose and brass
or plastic fittings. Use Teflon tape on
threaded pipe joints. Any number of
diffusers can be connected to a common
supply line. For flow distribution manifolds
and fittings consult your supplier. Supply
pressure must not exceed 50 psi (3.5 bar).
Use a preset pressure regulator (set to 50
psi) and back pressure compensated
flowmeter with needle valve to control flow
Alternatively, but not recommended, if an
adjustable pressure regulator is used to
control now, then this MUST BE USED in
conjunction with a 50 psi pressure relief
valve.

OPERATION

Ensure that the supply pressure at the
diffuser cannot exceed 50 psi (3.5 bar).
Pressurize the diffuser only when
submerged. Turn the gas on and control
flow via the needle valve on flowmeter. If an adjustable pressure regulator is being used
to control flow, ensure that the regulator is in the "Off" position i.e adjustment knob fully
screwed out (anti-clockwise) before turning on the gas supply. Slowly increase pressure
to the desired level, usually 20 to 30 psi (1.5 to 2 bar), by turning adjustment knob
clockwise. There will be a small delay before the diffuser responds to flow adjustments,
especially if the diffuser's air plenum has filled with water.
Brass inlet fittings for MBD600 and MBD300 diffusers
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