Bosch PROTANKLESS GWH 345/450 ESR - Manual (Page 33)

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Troubleshooting
33
Error lock-out is indicated by the orange LCD blinking. An error lock-out is done for safety reasons. After fixing the
problem, press the reset button to return the heater to service.
Only tank loading (no heating function). No heat demand by the thermostat,
thermostat not well adjusted, other
defect. • 1. Check thermostat position
• 2. Check electronic unit
1)
.
Only heating (no tank load function). No heat demand by the NTC, defect. • 1. Check NTC cable
• 2. Check water (filter, …)
• 3. Check Domestic hot water - NTC
(Tank)
• 4. Check electronic unit
1)
.
Low temperature (domestic hot water). To low burner power, burner ON / OFF. • 1. Check air vent
• 2. Check Adjustment of gas, gas
valve
• 3. Check Domestic hot water-NTC
• 4. Check electronic unit
1)
.
Insufficient water flow. • Low water pressure
• Filter, taps or heat exchanger with
dirt .
• 1. Check inlet pressure
• 2. Check filter, taps, heat exchanger
and clean .
1) Check connections, fuse or if there are visible damages.
Fault Indication Possible Cause Check
Table 16