Sequence - Noritz WHiC56 Service Manual

Sequence

Water heating
Connect power
Bypass Flow Control Valve and
Main Flow Control Valve move to
initial position setting
NO
Lightning safety
device normal
YES
Power ON/OFF button turn ON
Set. Temp. indicates on the display
Bypass Flow Control Valve and
Main Flow Control Valve open
Self-diagnosis
NO
Normal combustion
possible
YES
1
Overheat prevention
NO
device (Thermal fuse) normal
(Less than 221°C)
YES
2
NO
Main Flow Control Valve
normal
YES
3
NO
Bypass Flow Control Valve
normal
YES
NO
Setting 60°C or higher
YES
Bypass Flow Control Valve
3
closes
Hot water fixture opened
4
NO
Water Flow Sensor detects
> 2.0 L/min
YES
NO
Initial check
normal
YES
A
Warning indication
The unit will continue operate with the error code blinking
on the Optional Remote Controller.
Maximum output limited
NO
Use for less than
5years
Warning indication
Note 2) YES
Self-diagnosis
NO
Normal combustion
possible
YES
Warning indication
90
Warning indication
65
5
Water Inlet Thermistor
Warning indication
open or shorted
66
6
Water Outlet Thermistor
open or shorted
7
Heat Exchanger Thermistor
open or shorted
8
Exhaust Thermistor
open or shorted
< (L)WHiC56 only >
Circuit board
17
Gas Proportioning Valve
drive circuit abnormality
10
Flame Rod circuit abnormality
(1 A or more)
Condensate Container clogging
< Condensing Model only >
10
Self-diagnosis
NO
99
Normal combustion
possible
YES
90
14
31
32
33
35
70
abnormality
71
72
29
- 17 -
Shutdown procedure
Fix problem
Disconnect power
Gas Proportioning Valve
Display turns OFF
Error code stops flashing
Gas Solenoid Valve-1
Gas Solenoid Valve-2
Power ON/OFF button turn OFF
Gas Solenoid Valve-3
Gas Solenoid Valve-4
Hot water fixture closed
B
Hot water fixture closed
Water flow
NO
sensor detects
< 1.4 L/min
YES
Burner ON lamp
goes off
closes
Primary Gas Solenoid
Valve closes
closes
closes
closes
closes
Fan Motor post purge
Main Flow Control Valve
opens fully
Fan Motor stops
Has 6min. passed
NO
since hot water fixture
closed
YES
Heat Exchanger NO
Thermistor
< 40°C
Bypass Flow Control Valve
closes
Shutdown