Bosch C 1210 ESC Reference manual

Technical Service Bulletin:
Removing & Replacing The Water Valve
Models: C1210ESC, C1210ES, C1050ES, 940ES, 940ESO, 830ES
Introduction
 When replacing the watervalve, it is very important to drain all
water from the water heater beforehand to prevent water
damage to the internal electronics.
Tools needed:
 Phillips head screwdriver
 Bucket to catch draining water
 Plumber’s grease
Removing the water valve
1. Press On/Off button to Off and unplug power cord from electrical
outlet.
2. Loosen two Phillips head screws located at bottom rear of cover.
(Fig. 1).
3. Lift front cover upward and remove. (Fig. 1).
Step 1 Step 2
S
tep
1
S
te
p
2
Figure 1
4. Remove 3 Phillips screws from control unit (Fig. 2, step 1)
4. Place water heater‘s control unit into the service position.
(Fig. 2, step 2).
Step 2Step
2
Figure 2
Water
valve
5. Close installer supplied inlet and outlet shutoff valves.
6. Relieve water pressure from unit by opening pressure relief valve
on hot outlet side of unit. Have a bucket ready to catch the
draining water. Drain water from unit by removing cold water
inlet connection on bottom of heater.

Data subject to change without notice | Printed in the USA | BTC 740002319 A | 07.2010 Bosch Thermotechnology Corp.
Technical Service Bulletin
18 | Removing & Replacing The Water Valve
Bosch Thermotechnology Corp.
50 Wentworth Avenue
Londonderry, NH 03053
Tel: [phone]
Fax: [phone]
www.boschpro.com
7. Unplug smaller wire connectors (A) from water valve.
(Fig. 3).
8. Remove pipe clips (C) located at the base and side of water
valve. (Fig. 3).
9. With a rag ready to catch residual water, lift water valve upwards
to separate it from the brass inlet connection (D). (Fig. 3).
Please note certain models may not have a water lter screen in
the base of the water valve.
10. Again with a rag ready to catch residual water, pull water valve
from pipe (E). (Fig. 3).
11. Remove water valve from heater and remove main wire plug
connection (B) from water valve. (Fig. 3)..
A
D
E
F
C
C
F
A
D
E
F
C
C
F
Figure 3
Replacing the water valve
1. Lubricate o-rings (F) with plumbers grease to prevent o-ring
damage or leaks. (Fig. 3).
2. Install replacement water valve by seating the side pipe
connection (E) rst (Fig. 3). Be careful to push water valve body
past o-ring on connecting pipe.
3. Reconnect clip (C) for side pipe connection. (Fig. 3).
4. Reinstall water valve onto brass inlet tting (D) (Fig. 3). Be
careful to seat water valve body past o-ring on inlet tting.
5. Reconnect remaining clip (C) on inlet tting connection (Fig. 3).
6. Check that both clips (C) are seated correctly in the anges
(Fig. 2). Improper seating will result in water leaks.
7. Reconnect main wire plug connection (B) to water valve. (Fig. 3).
8. Reconnect smaller wire connectors (A) for the water valve and
temperature sensor wires. (Fig. 3).
9. Open installer supplied inlet and outlet shutoff valves and
inspect for water leaks.
10. If no water leaks are present, return control unit to normal
position and secure with 3 Phillips screws (Fig 2). Plug power
cord into electrical outlet and push power button back to "On"
position. If an error code appears on the heater display, reset
the unit with the reset button. If error code reappears on the
display, press power switch to Off and check all wire
connections.
11. Push power switch back to On. If no errors are present, replace
cover and return heater to normal operation.