Transcript AC Gauge Manifold Identification (PPT 1.5MB)

GAUGE AND
MANIFOLD
IDENTIFICATION
© Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence
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Hello, I want to show you the
gauges and manifolds we use at
Fresh or Freezing and talk about
how we maintain and test them.
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There are two main differences in
service gauge manifolds, ie normal
pressure and high pressure.
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Normal pressure manifolds are
used for everyday service of
refrigeration units, eg R22, R404a
systems.
© Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence
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High pressure manifolds are used for high pressure
refrigerants, eg R410A, R764.
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The thread size on the manifold and the attached gauge
lines determines the usage.
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Normal pressure manifolds use 1/4” flare threads,
whereas high pressure manifolds use 5/16” flare threads.
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Take care with manifolds fitted with sight glasses as
these can be easily damaged and the glass can fly out
of the manifold and injure you or somebody else.
© Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence
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Manufacturers colour code the outside
of the gauges to distinguish between
high pressure and low pressure
gauges.
The low pressure gauge or compound
gauge is colour coded blue and the
high pressure gauge is colour coded
red. Don’t confuse this with the
manifold gauge body. It’s not colour
coded.
The AC gauge hoses are colour coded blue, red and yellow.
Yellow connects to vacuum pump, reclaim unit or charge
refrigerant. Blue connects to the low pressure side. Red
connects to the high pressure side
Some manufacturers also colour code the hand valves.
The gauge hose ports are not colour coded.
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© Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence
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There are two types of manifold
gauges – the standard two valve
gauge manifold set and the
standard four gauge manifold
set.
© Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence
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
Maintaining and calibrating
Bourdon tube gauges means
following a few simple steps:
 periodically testing for leaks
 removing any residual
refrigerant then adjusting the
needle of the gauge to read 0
kPa at atmospheric pressure
 keeping gauge lines sealed to
keep out dirt and other
contaminants
replacing the rubber seals in the ends of the gauge lines,
and giving the gauge lines a visual check to look for
perishing of the lines, cracks in the outer covering of the
lines and any other signs of mechanical damage.
© Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence
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Other types of pressure
gauges such as
electronic gauges
require specialised
maintenance. This must
be carried out by
qualified people.
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And remember, if you
are unsure about how to
calibrate a gauge,
check with your
manager.
© Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence