Sinclair SCV-50EA Service Manual page 86

Note: when the ambient temperature is less than 8℃, inlet water temperature and temperature of plate heat exchanger is less
than 2℃, crankcase heater of plate works. CP appears. If inlet water temperature and temperature of plate heat exchanger is
more than 7℃, crankcase heater stops working and CP code disappears.
CL malfunction: To low water temperature protection in heating mode for 10-16kW.
To low water temperature protection in heating mode.
Whether the 4-way valve switch can switch normally
Check whether the 4-way valve coil fall off and the valve body jammed.
Check whether 4-way valve coil and body jammed.
Pb malfunction: Anti-freeze protection
The actual measured temperature of outdoor water outlet temperature and plate heat
exchanger temperature is less than 3 ℃ in cooling mode. Water inlet temperature and
plate heat exchanger temperature is less than 5 ℃ in heating mode and waiting mode.
Check whether water inlet sensor and plate heat
exchanger is fall off or damaged.（especially when the
outdoor temperature is lower than 0℃）
Place temperature sensor to the related position or replace it.
Note:
1)
The actual measured temperature of outdoor water outlet temperature and plate heat exchanger temperature is less
than 3 ℃ in cooling mode, the compressor stops running. But the water pump continue operating. If the temperature is
℃, Pb code disappears.
more than 8
2)
The actual measured temperature of outdoor water inlet temperature and plate heat exchanger temperature is less
℃
than 8 in waiting state, water pump works. The actual measured temperature of outdoor water inlet temperature and
plate heat exchanger temperature is less than 5
normal.
LED displays CL
NO
NO
YES
Replace 4-way valve
LED displays Pb
Anti-freeze protection
NO
YES
℃
Determine the location again.
YES
Whether the thermometer bulb of water
outlet and inlet location are right.
YES
Plug
again
NO
Replace main PCB
NO
Replace main PCB.
, the unit enter heating mode in force. Compressor works too. This is
84
YES
NO
well
Replace main
PCB
YES
Normal
protection
system