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38VYM
R-410A
GB - 13
E N G L I S H
Test procedure, Pump-down,
maintenance, guide for the owner and accessories
Test procedure
• Energize the system by putting the main supply switch in the ON
position.
• The following procedure should be done in sequence for each
indoor unit (INDOOR UNIT A1, INDOOR UNIT A2, INDOOR UNIT
A3, INDOOR UNIT A4,). If multiple units are operating
simultaneously, you cannot carry out the check for cross
connection between refrigerant piping and control wiring or
incorrect system configuration.
• Operate the indoor unit A1 in cooling mode.
After five minutes in cooling mode check if the difference
between the temperatures at the indoor unit air inlet and outlet is
8
°
C or more.
• Check that the other indoor units A2, A3, A4 are not running.
• Verify that there is no sound of flowing refrigerant.
• If above conditions are not correct, check the refrigerant piping
connection and control wiring connection.
• Switch indoor unit A1 OFF using the remote control.
• Repeat the above procedure for indoor units A2, A3, A4.
IMPORTANT:
Test each indoor unit separately.
Pump-down
Pump-down is an operation intended to collect all the system
refrigerant in the outdoor unit.
This operation must be carried out before disconnecting the
refrigerant pipes in order to avoid refrigerant loss to the
atmosphere, if it becomes necessary to disconnect the
refrigerant connections for unit repair, removal or disposal; in
this case, after removal, the unit must be delivered to an
appropriate disposal centre or the original dealer.
Shut off the liquid valves with the Allen wrench.
Turn the indoor units ON in cooling with the fan operating at high
speed. After 2 minutes of operation, shut the suction valves with the
same Allen wrench.
Turn the system OFF and switch the mains supply OFF.
Disconnect the pipes.
After disconnection, protect valves and pipes ends from dust.
Table V: Accessories
Description
Part number
38VYM 18
38VYM 28 38VYM 32
Wall bracket kit
38YL-900---001-40
Maintenance
The following maintenance operations must be carried out by
qualified personnel.
Cleaning the coil
If necessary, proceed as follows for more careful cleaning of the
coil:
Switch the mains supply OFF.
Remove unit top cover by losening the fixing screws and lifting the
cover.
Carefully clean the coil with a vacuum cleaner from inside to
outside.
With the same vacuum cleaner, remove the dust from inside the fan
compartment and the fan blades. Avoid any damage to the blades
which may cause future vibrations and noise.
Replace the unit cover and tighten the screws.
Guide for the owner
When installation and tests are completed explain the Operation
and Maintenance Manual to the owner, with particular attention to
the main operating modes of the air conditioner, such as:
• Turning the unit on and off.
• Functions of the air conditioner.
• Removal and cleaning of the air filters.
Leave the two installation manuals for the indoor and outdoor units
with the owner for future use during maintenance operations or for
any other needs.