XO 4 & XO FLEX TROUBLE SHOOTING GUIDE
Version 3.30 62
The backflow Prevention System is designed to avoid any risk of water contamination after mixing.
The system is maintained the container under pressure after filling. The system consists of a mixing cup,
a sensor, a backflow prevention tank equipped with non-return valve, air and water inlet pipes and two
No water in the container.
The check valve is defective.
Unscrew and remove the mixing
cup from above the container to
access the check valve. Unscrew
the plug and clean or replace it
It is very important that the check
valve is mounted correctly to
avoid any backflow into the
bucket when the container is
Sensor pins are not properly
placed in the mixing cup or are
Refer to chapter "Liquid sensor
PCB” AP-869" on page 54
The water supply valve V27 is
defective
Verify that the connectors are
properly inserted.
Measure the voltage at the coil
Measure the coil resistance
(≈100Ω).
Disassemble and clean the valve
at the piston.
Change the plunger seat gasket
The 3-way air supply valve V30
for pressurized air is defective
Check the voltage 24VDC on the
valve connectors.
Verify that the connectors are
properly inserted.
Measure the coil resistance
(≈100Ω).
Disassemble and clean the valve
at the piston.
Change the plunger seat gasket
replace if faulty, AO-777
The main water valve V10 (Ø3, 2-
way, 1/8RG) is defective.
WATER/AIR XO4 and XO Flex
Page 52 for explanation.
Verify that the connectors are
properly inserted.
Measure the voltage at the coil
connectors 24VDC
Measure the coil resistance
(≈100Ω).
Change if defective UC-584.
Disassemble and clean the valve
at the piston.
Change the plunger seat gasket