If You Have A Problem - Bosch PowerStar AE125 Handbook

Note: The unit will work at lower supply voltages but the following changes
Maximum output
Temperature control range
Maximum flow rate
(refer to Graph 1, Page 8)
WARNING
Always switch off the electricity supply to the unit before you remove the cover.

If you have a problem...

Service should only be performed by qualified personnel
Symptom
Cold water only –
neon light off.
Water too cold –
neon light on
10
15kW at 220V
13kW at 208V
87°F to 116°F at 220V
82°F to 108°F at 208V
84% of maximum at 220V
75% of maximum at 208V
Cause
Electricity not on or one of the
supplies has failed.
The water supply is connected
to the outlet of the unit.
One or more of the heater
module cut-outs has tripped.
Plumbing crossover.
The flow transducer is not
working.
Water flow is too high.
One of the power supplies is not
on.
The power supply voltage has
dropped.
Temperature dial is turned too
low.
The inlet water temperature has
dropped.
will apply:
22.5kW at 220V
20kW at 208V
87°F to 116°F at 220V
82°F to 108°F at 208V
84% of maximum at 220V
75% of maximum at 208V
What to do
Check electricity supply.
Reconnect the water supply to the inlet
of the unit (marked blue).
Turn off the power, open the unit and
reset by pushing the button(s) on the
top of the heater module(s). Establish
and fix the cause of the overheating.
Test by turning cold water supply off to
heater, then open hot water faucet(s).
No pressurized water flow should be
evident. If it is evident, then that
plumbing crossover needs to be
corrected for the heater to operate.
Turn off the power, open the unit and
observe if the flow transducer "spins"
when the water is turned on. If not,
contact BBT toll free at 866-330-2729.
Adjust the water flow (see Graph 1
on Page 8).
Check the supply voltages to the
heater and rectify if necessary.
This is likely an issue with the power
supply. Compensate for this by
increasing the temperature setting
(turn dial clockwise).
Turn the temperature control dial
clockwise.
Turn temperature knob up or reduce
the flow rate according to Graph 1
on Page 8.