Maintenance And Service - Bosch C 950 ES Installation Manual

6

Maintenance and service

Warning: Always shut off the electrical
power supply, shut off the manual gas
valve and shut off the water valves
whenever servicing.
Caution:
B Check and clean the complete water
heating system once a year.
B Carry out a maintenance overhaul if
necessary. Immediately repair defects to
avoid damage to the system.
Annual maintenance table
1. Inspect venting system
2. Inspect combustion chamber
3. Inspect burner
4. Inspect condensate trap
5. Inspect water filter
Table 23 Annual maintenance
6.1 Annual maintenance
(To remove front cover, see page 7.)
Venting System
• Venting system - inspect inside of flue pipe for any
blockage or restriction. Observe burner flames
during heater operation. (front cover must be
removed). Inspect the combustion air inlet pipe for
blockage or debris. Inspect combustion air and
exhaust terminations for blockage or debris.
Combustion Chamber
• Inspect burner observation window (Fig. 77, #14) for
cracks or spillage of flue gases. Observe burner
flames during heater operation. Flames should be
steady and blue with no signs of yellowing. Yellow
burner flames are an indication of improper
combustion. Refer to Section 3.4, page 24,
chapter 3.3, page 10 of this manual to verify exhaust
system and combustion
manufacturer's specifications.
Pressure Relief
• Manually open the pressure relief valve to ensure
proper operation.
6 720 646 812
Every year
X
X
X
X
X
air supply meets
Inlet Water Filter
• Verify the inlet filter screen is clean and undamaged.
The inlet water filter is located between the ¾" cold
water inlet fitting on the right side of the appliance,
and the water valve (See Fig. 33, page 29). Close
installer supplied water shutoff, carefully lift the water
valve, then rotate back. Remove filter, clean and or
replace if damaged.
Descaling
• In areas where the water supply has a high mineral
content, the heat exchanger should be flushed with a
descaling solution. Scale build up will shorten the life
of the water heater and damage resulting from scale
is not covered under warranty. Refer to section 6.3
for detailed instructions on descaling the heat
exchanger.
Fin Coils
• Inspect heat exchanger fincoil for soot build-up or
blockage. To access fincoil, consult service bulletin
at www.bosch-climate.us. If there is evidence of soot
build-up or blockage, the heat exchanger should be
removed by a professsional and cleaned thoroughly.
Condensate trap
• Check water level in the condensate trap, see Fig.
35.
• If appliance is out of service for more than 10 days,
fill as described on page 31.
• Check for debris and clean if needed.
6.2 Winterizing for seasonal use
The water heater must not be installed in a location
where it may be exposed to freezing temperatures. If the
heater must be left in a space which is likely to
experience freezing temperatures, all water must be
drained from the heater. If precautions are not taken,
resulting damage will not be covered under the
warranty. NOTE: Use of agents such as anti-freeze is
not permitted and voids the warranty, as they may cause
damage to the water heater's internal components.
1. Press ON/OFF switch on the water heater to turn
OFF the heater and unplug power supply cord. The
display should be blank.
2. Shut off gas supply to heater.
3. Shut off the water supply to the water heater using
installer supplied shutoff valve.
4. Open hot water taps to drain and relieve pressure
from the plumbing system. If water continues to flow
after 5 minutes, a crossover of the hot and cold water
pipes is present and must be corrected before
proceeding.
Maintenance and service
41