Re-Using Existing Field Piping - Daikin SkyAir Service Manual

Piping Diagrams
3.7

Re-using Existing Field Piping

3.7.1 Introduction
When installing a system using an RZQ outdoor unit, existing or pre-installed piping can be
used according to below specified conditions.
In all circumstances where these conditions can not be fully met, new piping has to be installed.
* RZQS can not be reused.
3.7.2 How to Re-use Existing Piping?
Notes: Oil contamination can be checked using the Daikin "Oil Checker Card".
Caution:
254
Check the existing Non-standard
pipe size. size
Standard size
All satisfactory
Check the existing pipe length.
50 m or less
See if the already installed air conditioner can operate and perform a
pump-down operation.
Both operation and pump-down are possible
After 30 minutes of cooling operation, proceed with pump-down operation
without interruption.
Remove the existing air conditioner.
Check the compressor (of the existing air conditioner) for fault records.
None
See if the contamination inside the existing pipe is acceptable.
OK
Rework the flare. (For R-410A: See table on page 278)
Use the supplied flare nut.
Existing piping work for new air conditioner
If copper piping is corroded, existing piping re-use is not allowed.
Single side thermal insulation is not allowed for re-use.
See further notes in this section for Twin, Triple and Double Twin applications.
Check the existing pipe size and thickness
referring to the "(1) SELECTION OF PIPING
MATERIAL" on page 274.
Check the following item in
"(2) REFRIGERANT PIPE SIZE" and
"(3) ALLOWABLE PIPE LENGTH AND
HEIGHT DIFFERENCE" on page 276.
See if the length requirements for re-using
the existing piping are as specified.
See if the reduction of cooling capacity
may cause any problem.
Longer than 50 m
Operation not possible
Pump-down operation
not possible
Exist
NO
SiBE28-804
Not listed
Beyond
allowable
length range
Reuse
of
No tolerance
existing
for capacity
reduction
pipe
not
allowed
Appendix