Pioneer YN020GMFI22M2D Service Manual page 12

6. Set the refrigerant container on an electronic
charging scale and record the weight (or zero-out
the scale depending on the scale used).
7. Start all indoor units attached to the system in
cooling mode and lower the set points on each of
their controllers to the minimum setting so the
system will not shut off during the procedure.
8. Refrigerant can now be added to the system, open
the low side valve at the low pressure side of the
gauge manifold set to start charging the unit with
liquid refrigerant. Please remember to nurse the
refrigerant in slowly by controlling the low side
valve at the Low pressure side of your gauge
manifold (open for 3 seconds and close for 10
seconds for the system to digest each load). Keep
track of the refrigerant being added into the system
(do not overcharge the system).
9. Once the correct charge has been added to the
system, close the low side valve at the low
pressure side of the gauge manifold set and check
the operating pressure. Keep running the system
continuously for 20 minutes and record the
pressure reading along with the indoor and outdoor
temperature readings for future reference. The
system is now charged and can be shut off.
10. Close the valve on the refrigerant container and
disconnect the hose from the manifold set, also
disconnect the hose from the 3-way (Gas) valve
where it is attached to the unit and replace and
torque all brass dust caps.
Be sure to use a torque wrench to tighten the
service port caps to a torque 18N·m (13.27 ft·lbs).
Always leak check all service ports after servicing
the refrigerant system.
5.5 Adding or replacing the refrigerant after
a refrigerant loss is discovered:
Please note: R410a is a blended and isotropic
refrigerant. If refrigerant is lost from your system in
significant amounts (exceeding 15% of the total
volume), the remaining refrigerant may no longer
contain the proper original ratio of the blend.
Therefore system must be entirely evacuated and
recharged with fresh refrigerant. If the system is
determined to have lost only a small amount of
refrigerant, it can be topped off using the same
procedure as covered above in paragraph 5.4.3,
until proper operating pressures and performance
are obtained. Prior to recharging refrigerant after a
leak is discovered, the leak itself must be located
and repaired to avoid the repeated refrigerant
losses. A well-sealed system will never need
refrigerant to be recharged as it stays as a sealed-
closed system entirely. Below procedure explains
complete evacuation and fresh refrigerant recharge
procedure.
Procedure
1. Keep all attached indoor units connected and
assure that all of the brass flare nuts at all pipe
connections both at the indoor and outdoor unit
connectors are tight and leak free.
2. Assure ALL of the 2-way (Liquid) and 3-way (Gas)
service valves of the utilized circuits (where an
indoor unit is attached) are fully open.
3. For 3, 4 and 5 zone systems, also assure that both
of the Common (Master) 2-way (Liquid) and 3-way
(Gas) service valves are fully open.
4. Assure that the 2-way (Liquid) and 3-way (Gas)
service valves of any unused circuit are fully closed.
5. Next step is different for 2 zone and 3/4/5 zone
systems. See 5a. and 5b. accordingly:
a. If servicing a Two Zone (dual split) system,
connect the low pressure hose on your gauge
manifold (usually blue) to the 3 way (Gas)
valve's service port, belonging to circuit A.
Additionally connect the high pressure hose on
your gauge manifold (usually red) to the 3 way
(Gas) valve's service port, belonging to circuit
B. (Ignore this if there is only one indoor unit
attached to the system. Single indoor units
should always be attached to circuit A.). Fully
open both the Low side valve on the low
pressure side and the High side valve on the
high pressure side of your gauge manifold.
(Keep the High side valve at the High pressure
side of the gauge manifold closed if there is
only a single indoor unit attached to the system)
If the manifold gauge set's hoses have 1/4"
SAE connections, two 1/4" to 5/16" SAE port
adapters will be needed, one for each circuit.
See below drawing.