15
Troubleshooting
6 720 612 217 (05.03)
Solar heating system pump
not running even though
symbol on the display is mov-
ing.
Break in connecting lead to
solar heating system pump or
lead not connected.
Check lead.
Fuse (SI, Fig. 10) has blown.
Check fuse and replace if
necessary.
Solar heating system pump
defective.
Check solar heating sys-
tem pump and replace if
necessary.
symbol on display is mov-
ing, solar heating system
pump is “humming”.
Pump is jammed.
Unscrew slotted-head
bolt from pump cover and
free pump shaft with a
screwdriver. Do not strike
the pump shaft!
Temperature sensor shows
incorrect reading.
Temperature sensor not fully
inserted in pocket or excessive
temperature loss at point of
measurement.
Push temperature sensor
all the way into pocket
and fix in position.
Provide insulation if nec-
essary.
Domestic hot water too hot
Storage tank temperature limit
set too high.
Set lower storage tank
temperature limit.
Domestic hot water not hot
enough (or not enough
domestic hot water).
Hot water temperature control
on boiler or heating program-
mer is set too low.
Set temperature accord-
ing to the relevant operat-
ing instructions
(recommended max.
60 °C).
Problem
Cause
Remedy
Table 6
