Problems - Bosch WR11B series Installation Manual And Operating Instructions

20 | Problems

8 Problems
Assembly, maintenance and repairs must be performed by qualified technicians only. The following chart offers
solutions to possible problems (solutions followed by an * must be undertaken by qualified technicians only).
Problem
The heater does not ignite.
Slow and difficult ignition of
the burner.
Red LED in switch flashes.
Water at low temperature.
Water is not heated, no flame.
The burner turns off the
heater is operating.
There is spark but the main
burner does not ignite.
Reduced water flow.
Table 9
6 720 648 592 (2011/06)
Cause
Switch turned off.
Reduced water flow.
Flat batteries.
Insufficient gas supply.
Temperature limiter has tripped.
Flue gas safety device has tripped.
No ionisation probe signal.
Insufficient water supply pressure.
Dirty taps or mixers.
Gas valve blocked.
Heat exchanger blocked
(limescale).
Solution
Check switch position.
Check and correct.
Replace batteries.
Check the temperature selector position
and adjust it according to the desired water
temperature.
Check reducer, and if inadequate or
malfunctioning, replace it.
Check if the bottles (butane) freeze during
operation, and if so, move them to a
warmer place.
Wait 10 minutes and restart the heater. If
the problem persists, call a qualified
technician.
Vent the area. Wait 10 minutes and restart
the heater. If the problem persists, call a
qualified technician.
Check:
• Gas supply,
• Ignition system (ionisation electrode and
electrovalves).
Check and correct. *
Check and clean.
Clean filter.*
Clean and de-lime if necessary.*