Mitsubishi Electric PUHY-RP-Y(S)JM-B, Data Book

Page: 230 / 293

227
3. Piping Design
SYSTEM DESIGN
3-1-6. Flow chart to check if the existing piping can be reused
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
YES
NO
NO
NO
Does the piping diameter
and piping length match
our guideline?
Please change to the specified
branch pipe.
Check the branch pipe type
and the reusability standards
to make a decision.
Is the branch pipe shape T, Y
or header branching?
Do the existing
pipes hold enough
air tightness?
All branch pipes are connected
with the indoor units.
Is the piping correctly covered
with heat insulation material?
Does the piping meet the
strength requirements?
(material,thickness,anti
corrosion)
Conduct heat insulation.
Please have air tight test on site.
The existing piping can be reused.
Use a new piping.
Did the existing unit before the
replacement operate without
any gas leak?
Cut the branch pipe completely that are not
in use, and seal it.
Is the piping air tight?
Start
YES
YES
YES
NO
NO
NO
NO
YES
YES
YES
NO
NO
Please contact your local
distributor.
Are the existing pipes still
connected with indoor units and the
outdoor units? (excluding sealed
branch pipes that are
not in use)
Exisiting piping cannot be
reused. Use new piping.
If the piping is left disconnected, there is a
possibility of contamination and corrosion
inside the pipe. Do not reuse such pipes.
Is the existing unit
Mitsubishi Electric unit?
Is the capacity of new
replacement unit the same as that
of the existing unit?
Check the piping size and length.
Is the refrigerant oil SUNISO, MS,
Barrel Freeze, HAB or Freol?
The vertical height
difference needs to be 50m or
less between IU and OU (if OU is
below IU, 40m or less). And also, height
difference between each IU is
15m or less.
Take the refrigerant oil recovery
procedures described in the Mineral
Oil Collection (Refrigerant Oil
Recovery) Manual.
Do you know what kind of
refrigerant oil is used in the
existing system?