Procedure Of Reuse Of Existing Piping - Daikin VRV II-Q RQYQ8-48PY1B Service Manual

Features
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.
Check any failure or frequent additional refrigerant charging due to gas leakage or
other causes.
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.
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.
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.)
Check the status of pipe insulation. Also check for loosening of the piping support.
(Both gas pipe and liquid pipe need to be insulated.)
Refrigerant recovery in current system (R-22, R-407C)
(Continued on the next page)
12
No failure found or failures
have been repaired.
No abnormality found
Within the range
OK
Failure found and not
repaired.
Abnormality
found
Usable if the refrigeration oil to
be used is SUNISO, MS, HP-
5S, HAB, Barrel Freeze, Freol,
ethereal oil or ester oil.
Out of the range or
corrosion detected
Large pressure loss or
design pressure is low
SiBE341027
New piping has to
be installed.
No
Yes
Repair the problems.
OK
Newly install and
replace the branch
section.
OK
General Information