Service Manual

3. Piping work and refrigerant charge
79
SMGB0079 rev.0 - 01/2013
3
3.6 Piping work for compatibility with the piping of current installations where is
used R22 or R407C.
N O T E
ContactyourHitachidealerforspecicsupportonyourinstalation.
The new IVX Premium and IVX Standard are compatible with those installations that have been operating with R22 or
R407C. This allows installing the IVX Premium/Standard Outdoor Units, which operate with R410A, without having to
change piping installation.
3.6.1 Installation procedure for existing pipes
N O T E
• Forsystemswithseveralindoorunits,branchpipesshallbechangedtoHitachi-speciedmodelforIVXPre-
miumandStandard(R410A).
• ExistingoutdoorandindoorunitsforR22orR407Ccannotbeused.
1 Recover refrigerant (R22 or R407C):
a. Compressor of the existing unit is working
Pump down. Perform refrigerant recovery operation of existing air conditioner without stopping during 30 minutes
in cooling mode.
b. Compressor of the existing unit is not working
Recover refrigerant with a refrigerant recovery device.
2 Remove existing air conditioning system (Outdoor and Indoor unit).
3 For the existing pipes, proceed with one of the following operation:
a. Clean the existing piping (see section 3.6.1.1)
b. Connect renewal kit (optional accessory)(see section 3.6.1.2)
4 Connect new UTOPIA IVX Premium/Standard series
5 Vacuum process.
6 Refrigerant charge (R410A)
Follow the normal process described for determinate if it is necessary additional refrigerant charge..
C A U T I O N
RecoveringR22andR407Cismandatorytoremoveanexistingairconditionerandpiping.Donotventintothe
atmosphere.
3.6.1.1 Conditions to use a existing pipes with cleaning process
After the piping cleaning process, follow the normal installation process as a new piping installed, considering all the res-
trictions and limitations. Special atention is required for control the piping thickness.
3.6.1.2 Conditions to use a existing pipes without cleaning process
A Renewal Kit (sold separately) can be used even in cases where there is a history of Compressor failure, allowing diver-
sion to existing piping without cleaning. Thus, the burden of installation works at renewal can be reduced.
Existing pipes can be used without cleaning if the following conditions are satised:
1 Install the Renewal kit (mandatory).
2 Maximum piping length 50 m. (If the pipe is longer than 50m, existing pipes can be used if cleaning is performed)
3 The capacity of the new unit must be equivalent at the one installed previously.
4 No corrosion No cracks, No scratches or deformations in existing pipes.
5 Dirt insider the pipes shall not be noticeable.
6 Piping thickness, Flare Nuts, gaskets, etc. shall be compliant products.
7 Flare shall be reprocessed.
8 Piping airtight or vacuuming shall be performed precisely as new piping.
3.6.2 When existing Air-Conditioner is a product of another manufacturer
Existing pipes made by other manufacturer can also be used if the following conditions satised:
1 For systems with several indoor units, branch pipes shall be changed to Hitachi-specied model.
2 Please perform a pipe cleaning.