15-6.Connecting Refrigerant Pipes And Drain Pipes - Mitsubishi Electric City Multi PWFY-P100VM-E-BU Data Book

15. INSTALLATION
15-6. Connecting refrigerant pipes and drain pipes
15-6-1. Refrigerant piping work
This piping work must be done in accordance with the installation manuals for both outdoor unit and BC controller/WCB
(simultaneous cooling and heating R2-Series).
 R2-Series is designed to operate in a system that the refrigerant pipe from an outdoor unit is received by BC controller/
WCB and branches at the BC controller/WCB to connect between indoor units.
 The PWFY unit should be connected to 2 ports on the BC controller. (Set BC controller DIP SW 4-6 to ON)
 For constraints on pipe length and allowable difference of elevation, refer to the outdoor unit installation manual.
 The method of pipe connection is brazing connection.
 Install the refrigerant piping for the indoor unit in accordance with the following.
1) Cut the tip of the indoor unit piping, remove the gas, and then remove the brazed cap.
2) Pull out the thermal insulation on the site refrigerant piping, braze the unit piping, and replace the insulation in its original
position. Wrap the piping with insulating tape.
 Pay strict attention when wrapping the copper piping since wrapping the piping may cause condensation instead of
preventing it.
 Before brazing the refrigerant piping, always wrap the piping on the main body, and the thermal insulation piping, with
damp cloths to prevent heat shrinkage and burning the thermal insulation tubing.
Take care to ensure that the flame does not come into contact with the main body itself.
(A)
(B)
(A)
(D)
(E)
(F)
15-6-2. Mixed system of PWFY-AU and Indoor unit (Y, HP (ZUBADAN), WY system)
Take one of the countermeasures listed below.
1) Install the External Solenoid Valve (except on PWFY-EP100VM-E2-AU)
2) Add brine, assuming that the temperature will drop to -20°C.
Set Dip SW 1-10 (on ATW unit) to ON if brine is added.
*Refer to P62 "Brine" in section 15-7. Water pipe installation.
* With the WY system, the above steps apply only when operating the WY at the water temperature below 10ºC.
MEES19K013
(C)
(A) Thermal insulation
(B) Pull out insulation
(C) Wrap with damp cloth
(D) Return to original position
(E) Ensure that there is no gap here
(F) Wrap with insulating tape
(A) Cut here
(B) Remove brazed cap
AIR TO WATER
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