- 19 -
USE
USEFUL ADVICE
Fig. 3.4
Another possible signal occurs when the
d.h.w. exchanger cannot exchange all of the
power supplied by the boiler.
E.g.: d.h.w. exchanger clogged with lime
scale. This happens only when the boiler
has a request for d.h.w..
Code
01
appears on the LCD display that al-
ternates with the letter
Li
. The display back-
ground fl ashes ( Fig. 3.5 ).
Fig. 3.5
In order to reset good function-
ing of the boiler, call a compe-
tent and responsible Service
Engineer.
Noise due to air bubbles are heard dur-
ing operation
You should check that the pressure on the
pressure gauge is not below the correct set-
ting.
If required, top up the system correctly, as
described in the
section "Refi lling proce-
dure" to page 12 of this manual. Bleed any
air present in the radiators, if necessary.
The pressure on the pressure gauge has
gone down
It is necessary to top up the appliance with
water again, so as to raise the pressure to
an adequate level as described in the
sec-
tion "Refi lling procedure" to page 12
of this
manual. If topping up with water has to
be done very frequently, have the system
checked for leaks.
Water comes out of the pressure relief
valve
Check on the pressure gauge that the pres-
sure in the central heating circuit is not
close to 3 bars. In this case, temperature
rise in the circuit can cause the pressure
relief valve to open. So that this does not
happen and to decrease the pressure to a
normal value, it is advisable to vent some of
the water in the appliance through the bleed
valves present in the radiators.
Reduced domestic hot water tempera-
ture
The likely causes may be impurities caught
in the domestic hot water fl ow switch fi lter or
limescale deposited in the domestic hot wa-
ter heat exchanger. It is advisable to have
the appliance cleaned out by an Authorised
