CT-23
page 2 of 2
rev 10/06
Bosch Water Heating
340 Mad River Park, Waitsfield, VT 05673
©
BBT
NORTH AMERICA CORPORATION
Bosch Group
D. Rebuilding water valve
1. Place diaphragm in right side of water valve, ensuring
that ring on outer edge is in recess.
2. Liberally lubricate both ends of new pushrod and
install pushrod assembly into water valve cover,
pressing firmly in place with thumbs. (Fig. 3 pos. 10)
3. Reassemble 2 halves of water valve with metal retain-
ing plate. Install and tighten 5 cover screws (Fig. 2).
4. Install volumetric flow governor with plug and retain-
ing clip. Lubricate O-ring on plug before reinserting.
5. Lubricate O-rings on venturi and install.
6. Install inlet water filter and threaded bushing with
retaining clip.
E. Installing water valve
1. Remove, lubricate and reinstall water valve set
screws in gas valve. Do not thread screws in fully. 1
to 2 revolutions maximum (Fig. 1).
2. Firmly seat water valve into right side of gas valve
with temperature adjustment shaft facing outward
(Fig. 3, pos 11).
3. Now tighten set screws fully and evenly.
4. Lubricate O-ring on pipe to heat exchanger, put into
water valve and secure with retaining clip from top.
5. Reconnect cold water inlet flex pipe with washer.
FIGURE 3
F. Testing operation
Important: Before firing the heater, run water through
heater to check for leaks and purge air.
1. Replace and tighten cover and reinstall knob(s).
2. 1000P, 1600P, 260PN, 425PN models: light pilot and
slide control to the right to large flame position.
3. Shut off water at heater inlet and open hot water
faucet.
4. Turn temperature adjustment knob to full clockwise
position.
5. Slowly open inlet water supply just until burners
ignite and no further.
6. Measure water flow at open faucet to verify proper
activation rate of 0.6 gallon per minute (quart in 25
seconds or gallon in 100 seconds).
7. Shut water off at heater and observe burners to
verify that they go out immediately when water flow
stops.
WATER VALVE REBUILD
1. Water valve cover screws (5)
2. Water valve diaphram
3. Push rod
4. Push rod sleeve
5. Threaded bushing
6. Water filter
7. Flow governor retaining clip
8. Volumetric flow governor
9. Venturi
10.Water valve cover
11.Temperature adjustment shaft
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.