Features
SiBE341027
12
General Information
5.3
Procedure of Reuse of Existing Piping
If you are using the existing piping, follow the steps below:
Check whether the existing refrigerant piping is available or not.
Repair the problems.
Refrigerant recovery in current system (R-22, R-407C)
OK
No
Yes
OK
OK
Check any failure or frequent additional refrigerant charging due to gas leakage or
other causes.
New piping has to
be installed.
Check the existing air conditioner for the manufacturer, model name, existing
piping system, pipe laying, layout of indoor/outdoor units, size of each pipe, shape
of branch, refrigeration oil to be used, etc.
Usable if the refrigeration oil to
be used is SUNISO, MS, HP-
5S, HAB, Barrel Freeze, Freol,
ethereal oil or ester oil.
Check whether the pipe size, piping length (actual/equivalent length, height
difference), design pressure of local piping (3.3MPa or more) are within the range
of operational conditions. Also check the presence of corrosion in the pipes.
No abnormality found
Within the range
Abnormality
found
No failure found or failures
have been repaired.
Out of the range or
corrosion detected
Check the branch pipe. Usable if it is the branch pipe used for DAIKIN's VRV or if
it is other manufacturer's T tube, Y tube, and header branch type and has a
designed pressure of 3.3MPa or more. (Not usable in a special case, for example,
the pipe with pressure reduction.)
Newly install and
replace the branch
section.
Check the status of pipe insulation. Also check for loosening of the piping support.
(Both gas pipe and liquid pipe need to be insulated.)
(Continued on the next page)
Failure found and not
repaired.
Large pressure loss or
design pressure is low
