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Problem solving
Ionization failure during operation.
1. Check gas type,
Fig. 2
,
page 6
.
2. Check three wire connections to ignition group on the lower
front of the heat exchanger are secure.
3. Verify that venting specifications are met. Improper venting may
cause premature failure of the flame sensor rod. See
chapter 3.3
,
page 10
.
4. Check gas pressure. See
chapter 3.14, page 35.
5. Check and adjust CO
2
readings. See
chapter 6.5, page 43.
6. Check that the minimum power fan speed has been adjusted to
the proper value. See
page 20
.
Internal hardware/software failure.
1. Disconnect power supply cord and check the two wire and
ground connections on control board as well as ground connection
on heater chassis.
2. Pressing the wrong combination of buttons on the control unit
can create confusion among the microprocessors inside. In this
case, the error code should not happen more than once or twice.
Turn off the water heater. Turn water heater back on and try
resetting error code. Use the reset button (
) to reset any error
codes.
3. Possible defective control unit call Bosch Water Heating for
further instructions.
Ionization error at standby.
1. Loose connection to the flame ionization rod. Verify that the
thinner wire leading from the control unit is securely connected to
the set of electrodes located on the lower front of the heat
exchanger.
2. Flame ionization rod or control unit may be damaged. Contact
Bosch Water Heating for further instruction.
Gas leakage error, gas valve circuit
not closing properly.
1. Disconnect power supply cord and check wire connections on
gas valve and the two connectors on the control board.
2. Flow water out of a hot water tap above the minimum activation
point of 0.5 GPM. Measure voltage at the gas valve wire plug
connection. The voltage should measure 24VDC between the left
pair of wires and 24VDC between the right pair of wires when the
unit is operating. If voltage is not proper, contact Bosch Water
Heating for further instruction.
3. Gas valve may be defective, contact Bosch Water Heating for
further instrucation.
Display
Cause
Solution
Table 29
* By installer or service technician only.
Содержание C1050ES
Страница 56: ...6 720 646 812 56 Functional scheme 11 Functional scheme Fig 76 Functional scheme ...
Страница 58: ...6 720 646 812 58 Interior components diagram and parts list Fig 78 Appliance overview ...
Страница 69: ...6 720 646 812 Notes 69 15 Notes ...
Страница 70: ...6 720 646 812 70 Notes ...
Страница 71: ...6 720 646 812 Notes 71 ...