Mitsubishi Electric PUZ-HWM140VHA Service Manual page 8

2-3. PRECAUTIONS WHEN REUSING EXISTING R22/R410a REFRIGERANT TOOLS
Cautions for refrigerant piping work
Tools for R32 (The following table shows whether conventional tools can be used or not.)
Tools and materials Use
Gauge manifold Air purge, refrigerant
charge and operation check
Charge hose
Gas leak detector Gas leak check
Refrigerant recovery equipment Refrigerant recovery
Refrigerant cylinder Refrigerant charge
Safety charger Prevent compressor malfunction
when charging refrigerant by
spraying liquid refrigerant
Charge valve Prevent gas from blowing out
when detaching charge hose
Vacuum pump Vacuum drying and air purge
Weld the pipes
Welder and nitrogen gas cylinder
Refrigerant charging scale Refrigerant charge
Vacuum gauge or
Check the degree of vacuum.
(Vacuum valve prevents back
thermistor vacuum gauge
flow of oil and refrigerant to
and vacuum valve
thermistor vacuum gauge)
Charging cylinder Refrigerant charge
× : Prepare a new tool. (Use the new tool as the tool exclusive for R32.)
△ : Tools for other refrigerants can be used under certain conditions.
〇 : Tools for other refrigerants can be used.
2-4. PRECAUTIONS FOR SALT PROOF TYPE "-BS" MODEL
Although "-BS" model has been designed to be resistant to salt damage, observe the following precautions to maintain the
performance of the unit.
1. Avoid installing the unit in a location where it will be exposed directly to seawater or sea breeze.
2. If the cover panel may become covered with salt, be sure to install the unit in a location where the salt will be washed away by
rainwater. (If a sunshade is installed, rainwater may not clean the panel.)
3. To ensure that water does not collect in the base of the outdoor unit, make sure that the base is level, not at angle. Water
collecting in the base of the outdoor unit could cause rust.
4. If the unit is installed in a coastal area, clean the unit with water regularly to remove any salt build-up.
5. If the unit is damaged during installation or maintenance, be sure to repair it.
6. Be sure to check the condition of the unit regularly.
7. Be sure to install the unit in a location with good drainage.
2-5. Choosing the outdoor unit installation location
OK
OK
OCH748
R32 tools Can R22 tools be used?
Tool exclusive for R32
Tool exclusive for R32
Tool for HFC refrigerant
Tool exclusive for R32
Tool exclusive for R32
Tool exclusive for R32
Tool exclusive for R32
△  ( Usable if equipped with
Tools for other refrigerants
can be used if equipped with
adapter for reverse flow check
Tools for other refrigerants can be used
Tools for other refrigerants can be used
Tools for other refrigerants
can be used
Tool exclusive for R32
OK
NG
Can R407C tools be used? Can R410a tools be used?
×
×
×
×
×
×
×
△  ( Usable if equipped with
adapter for reverse flow) adapter for reverse flow)
〇
〇
〇
×
R32 is heavier than air—as well as other refrigerants—
so tends to accumulate at the base (in the vicinity of the
floor). If R32 accumulates around base, it may reach a
flammable concentration in case room is small. To avoid
ignition, maintaining a safe work environment is required
by ensuring appropriate ventilation. If a refrigerant leak is
confirmed in a room or an area where there is insufficient
ventilation, refrain from using of flames until the work
environment can be improved by ensuring appropriate
ventilation.
Install outdoor units in a place where at least one of the
four sides is open, and in a sufficiently large space with-
out depressions.
8
× 〇
× 〇
〇 〇
× 〇
× ×
× 〇
× 〇
△  ( Usable if equipped with
adapter for reverse flow)
〇 〇
〇 〇
〇 〇
×
─