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Note: The first and largest capacity indoor unit
should always be connected to circuit A as primary.
4.
If the manifold gauge set’s hoses have 1/4” SAE
connections, a 1/4” to 5/16” SAE port adapter will
be needed. (sold separately).
5.
Connect the center hose of the gauge manifold
(usually yellow) to the vacuum pump.
6.
Fully open the manifold valve on the low (blue)
side of your gauge manifold. Ensure that the manifold
valve on the high (red) side of your gauge manifold
stays closed.
7.
Start the vacuum pump, and operate according to
pump manufacturer’s specifications. If your vacuum
pump has a valve, open it as well.
8.
Perform vacuuming/evacuation for a minimum
period of 30 minutes, and check that the low pressure
gauge indicates a vacuum of -30 in/hg (500 microns).
(A more sensitive vacuum gauge should be used if
available).
9.
If the proper vacuum cannot be achieved within
30 minutes, the vacuum pump should be kept
running for an additional 15 minutes. If after the
additional 15 minutes of operation, the vacuum still
cannot be achieved, there could be a leak at one or
more of the flare pipe connections at either end of
a refrigerant pipes. The leak must be located, and the
leaking nut must be tightened properly before
re-vacuuming the circuit.
10.
If the vacuum is achieved, close the manifold
valve at the low (blue) side on your gauge manifold
first, and shut the vacuum pump off. Leave the gauge
manifold set and the hoses connected, and recheck
the vacuum reading 15 minutes later to verify that
there is no vacuum loss. (Very small increases in
vacuum level is normal).
11.
Circuit A is now dry and free of contaminants. Do
not remove the hose of your gauge manifold set from
the service port.
14.
Remove the 2-way (liquid) service valve’s brass cap
of circuit A. Insert proper size Allen wrench into the
valve core, and turn it counter clockwise for 1/4 turn,
wait 5 seconds and quickly close the valve by turning
it in the reverse direction. Check your low pressure
gauge on the manifold to verify that it now indicates
positive pressure of approximately 80 to 120 PSI in
your lines.
Cap
Valve body
Valve stem
Flare nut
2-way (liquid) service valve
15.
Apply soap-water mixture on both the indoor
unit connections and the outdoor unit connections
for circuit A with a soft brush to check for leakage
at the connecting points of the piping. If you notice
air bubbles, the specific connector has leakage and
must be tightened to stop the leakage.
(An electronic leak detector will be more efficient to
use for this, if available).
16.
Re-insert proper sized Allen wrench into the valve
core of the liquid service valve (2 way) for circuit A,
and turn it counter-clockwise until it is fully back
seated. Do not force it, once it stops turning. Repeat
the leak-checking procedure entirely on all
connections of circuit A. If you find a new leak,
close the 2-way (liquid) service valve you just
opened first, and tighten the flare nut at the leaking
connection until the leak is sealed. Reopen the 2-way
(liquid) service valve, and check again.
17.
Remove the 3-way (gas) service valve’s cap for
circuit A. Insert proper sized Allen wrench into the
valve core, and turn it counter-clockwise until it is
fully back seated. Do not force it, once it stops
turning.
Procedure 12 & 13 are for 3, 4, and 5 zone only, and
need to be performed only once in the beginning:
12.
Remove the 2-way (liquid) MASTER valve’s brass
dust cap. Insert a proper sized Allen wrench into the
valve core, and turn it counter clockwise until it is fully
back seated. Do not force it, once it stops turning.
13.
Remove the 3-way (gas) MASTER valve’s brass
dust cap. Insert a proper sized Allen wrench into the
valve core and turn it counter clockwise until it is fully
back seated. Do not force it, once it stops turning.
Flare nut
Cap
Valve body
Valve stem
3-way (gas) service valve
Manifold Gauge
Low pressure gauge
-76cmHg
Low pressure valve
High pressure
valve
Blue (low) hose
Yellow (middle) hose
High pressure gauge
Outdoor Unit Service Valve Set (GAS and LIQUID Valves)
LARGE DIA (GAS)
Service Valve
SMALL DIA (LIQUID)
Service Valve
