Procedure For Flushing The Heat Exchanger; The Preparation Of The Flushing System - Noritz NR501-OD Service Manual

Procedure for Flushing the Heat Exchanger

This procedure is only intended for use by
Service Representative. Any unauthorized use of this procedure may result in voiding the
warranty.Please contact Noritz America (866-766-7489) for additional support.
If the error code "C #* - C #*"
in the Heat Exchanger
Damage to the water heater due to Scale Build-up is not covered by the water heater's warranty.
To clear the error code "C #* - C #*", the Heat Exchanger
If the error code "C #*" is display
America (866-766-7489).
* = 1, 2, 3, 4, F
#
= 1, 2, 3, 4, 5, 6, 7, 8, 9, A, b, C, d, E, F
** Connect the "blue connector" fo
After connecting it, the water heater is set to "Flushing Mode".
The water heater must remain connected to electrical power
< 1.
1. Close the gas supply valve.
2. Close the water inlet valve (V1) and the water outlet valve (V2).
3. Connect the one drain hose (H1) to the drain valve (V3), and then the other to the circulating
pump.
4. Connect the drain hose (H2) to the circulating pump.
5. Connect the drain hose (H3) to the drain valve (V4).
6. P
*** Noritz recommends "White Vinegar".
7. Place the both drain hoses (H2 and H3) into the buck
Isolation valves**** are necessary for
V4
V2
Bu cke t
Flushing
Solution
**** Isolation valves may be purchased as an accessory from an authorized Noritz wholesaler.
They allow f
Contact Noritz America for more information (866-766-7489).
rvice professional or authorized Noritz
ay Windo w, it means there is Scale Build-up
ay Window, please contact Noritz
r.
bucket.
r.
V1
V3
H3
H2
Circulating
Pump
57
ve the Scale Build-up.
r.
(Ex. NRC711-DV)
Wa ter Heater
Display Window
V4
V3
V1
V2
H1
Wa ter
Wa ter Gas
Outlet Inlet Supply
Continue to connect
Gas
Suppy
Va lve