System Details 67
4.11.10 Water Adjustment Valve
Part
Check Point
Function
To control the water flow to maintain steady hot water temperatures.
Failure Event
The valve cannot modulate or open/close in CASCADE mode.
Effects
1. Water Adjustment Valve is not operating properly.
2. Abnormal flow detected during normal operation. “E434” displayed.
3. Temperature fluctuations at the hot water outlet.
Error Code
E434
Diagnostic
1. Visual inspection: Connection and/or breakage of wires. Clean the Domestic cold water inlet filter.
2. Voltage check: Check range of voltage shown below.
Color/Number
of wires
●
RED-BLACK: DC 12 V
●
WHITE-BLACK Start position: DC 0 V
Any open position: DC 5 V
●
BLUE-BROWN: PULSE
ORANGE-YELLOW
OUT
IN