Daikin FTXA20AW - Repair Procedures

2 | Components
Service manual
43
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
When outdoor temperature does not allow the unit to run in cooling or heating
mode
INFORMATION
Follow this procedure when the outdoor temperature is outside the temperature
range for one of the operation modes (Heating or Cooling). The unit CANNOT
operate in the mode for which the outdoor temperature is outside its temperature
range. See the databook on Business Portal for the temperature range of the
operation modes.
1 With the unit operating, connect the service monitoring tool to the unit and
check whether the unit is operating in Heating or Cooling mode.
2 Check with a contact thermometer (or by touching) if the flow through the 4-
way valve corresponds with the flow shown in the flow diagram of the specific
operation mode. (See "5.3Piping diagram"[4176]).
Is the flow correct? Action
Yes 4‑way valve is OK. Return to the
troubleshooting of the specific error
and continue with the next procedure.
No Perform the next step of this procedure.
3 Connect a manifold to one of the service ports of the refrigerant circuit and
check the pressure (suction, discharge). Compare with normal operation
conditions of the unit.
Refrigerant pressure correct? Action
Yes Replace the body of the 4‑way valve,
see "2.1.2Repair procedures"[443].
No Leaks may be found in the refrigerant
circuit. Perform a pressure test of the
refrigerant circuit, see "3.2.1Checking
procedures"[4158].
2.1.2 Repair procedures
To remove the 4-way valve coil
Prerequisite: Stop the unit operation via the user interface.
Prerequisite: Turn OFF the respective circuit breaker.
Prerequisite: Remove the required plate work, see "2.14Plate work"[4120].
Prerequisite: If needed, remove any parts to create more space for the removal of
the 4‑way valve coil.
1 Remove the screw and remove the 4‑way valve coil from the 4‑way valve
body.