Emptying The Domestic Hot Water Circuit; Commissioning; Preliminary Checks; First Commessioning - Beretta Ciao 25C Installer And User Manual

- Connect a pipe to the system discharge tap (C), then manually turn it coun-
terclockwise to let the water flow out.
- Once the operations have been completed, remove the pipe from the system
discharge tap (C) and close it again.

2.10 Emptying the domestic hot water circuit

Whenever there is risk of frost, the domestic hot water system must be emptied
in the following way:
- turn off the main water supply tap
- turn on all the hot and cold
- drain the lowest points.

3 COMMISSIONING

3.1

Preliminary checks

First ignition is carried out by competent personnel from an authorised Technical
Assistance Centre. Before starting up the boiler, check:
ƒ that the data of the supply networks (electricity, water, gas) correspond to the
label data
ƒ that the extraction pipes of the flue gases and the air suction pipes are wor-
king correctly
ƒ that conditions for regular maintenance are guaranteed if the boiler is placed
inside or between items of furniture
ƒ the seal of the fuel adduction system
ƒ that the fuel flow rate corresponds to values required by the boiler
ƒ that the fuel supply system is sized to provide the correct flow rate to the
boiler, and that it has all the safety and control devices required by current
regulations
ƒ that the circulator rotates freely because, especially after long periods of
inactivity, deposits and/or debris can prevent free rotation (see paragraph
"7.4 Unlock of the circulator").
3.2

First commessioning

On first ignition after prolonged inactivity and after maintenance, before putting
the appliance into operation it is essential to fill the condensate collection siphon
by pouring about 1 litre of water into the boiler combustion analysis take-off and
check:
- floating of the safety shutter
- the correct flow of water from the boiler outlet discharge pipe
- the leaktightness of the condensate drain connection line.
Correct operation of the condensate drain circuit (siphon and pipes) requires
that the condensate level does not exceed the maximum level (max). Prior fil-
ling of the siphon and the presence of the safety shutter inside the siphon is
designed to prevent the escape of combustion gases into the environment.
3.3

Venting cycle

Position the system's master switch to the "on" position.
Every time the boiler is powered, a 4-minute venting cycle is run. The di-
splay shows .
To interrupt the venting cycle, press the key shown in the figure below.
o o o
b
When the venting cycle is running, all heat requests are inhibited
apart from DHW unless the boiler is OFF.
The venting cycle can also be interrupted (if the boiler is not OFF) by a
DHW request.
3.4

Setting the thermoregulation

The thermoregulation is only available if an external probe is connected, and is
only active for the HEATING function.
THERMOREGULATION is enabled in the following way:
ƒ set parameter 418 =1.
With 418 = 0 or the external probe disconnected, the boiler works with a fixed
point. The temperature value measured by the external probe is visualised in
"4.3 INFO menu " under item I009.
The thermoregulation algorithm will not use the measured external tempera-
ture value directly, but rather a calculated external temperature that takes into
account the building's insulation: in buildings that are well insulated, the outdoor
temperature variations will have less impact than those that are poorly insulated
by comparison.
This value can be viewed in the INFO menu under item I010
1
1 88
8 .
9
REQUEST FROM OT CHRONOTHERMOSTAT
In this case, the delivery setpoint is calculated by chronohermostat on the basis
of the external temperature value and the difference between the real ambient
temperature and the required ambient temperature.
REQUEST FROM ROOM THERMOSTAT
In this case, the delivery setpoint is calculated by the adjustment board on the
basis of the external temperature value, to obtain an estimated ambient tempe-
rature value of 20° (reference ambient temperature).
There are 2 parameters that compete to calculate the output setpoint:
ƒ slope of the compensation curve (KT) - editable by technical staff
ƒ offset on the reference ambient temperature - editable by the user.
TYPE OF BUILDING (parameter 432)
It is indicative of the frequency with which the value of the calculated outdoor
temperature for thermoregulation is updated, a low value for this value will be
used for buildings that have little insulation.
SEXT REACTIVITY (parameter 433)
It is an indication of the speed with which variations of the measured outdoor
temperature affect the calculated outdoor temperature value for thermoregula-
tion, low values indicate high speeds.
Choice of the thermoregulation curve (parameter 419)
The thermoregulation curve for heating maintains a theoretical temperature of
20°C indoors, when the outdoor temperature is between +20°C and -20°C. The
choice of the curve depends on the minimum outdoor temperature envisaged
(and therefore on the geographical location) and on the delivery temperature
envisaged (and therefore on the type of system). It is carefully calculated by the
installer on the basis of the following formula:
KT = delivery T envisaged - Tshift
20- min. design external T
Tshift = 30°C standard system
25°C floor system
If the calculation produces an intermediate value between two curves, you are
advised to choose the thermoregulation curve closest to the value obtained.
Example : if the value obtained from the calculation is 1.3, this is between curve
1 and curve 1.5. Choose the nearest curve, i.e. 1.5. The settable KT values are
as follows:
ƒ standard system: 1.0÷3.0
ƒ floor system 0.2÷0.8.
Parameter 419 can be used to set the required thermoregulation curve:
CURVE DI TERMOREGOLAZIONE
100
90
T HT
T AT
80
70
60
T LT
50
T BT
40
30
20
20 15 10
external temperature (°C)
Temperatura esterna (°C)
T HT maximum heating setpoint temperature (standard systems)
T LT maximum heating setpoint temperature (free-standing systems)
Offset on the reference ambient temperature
In any case, the user can indirectly modify the HEATING setpoint value by defi-
ning, for the reference temperature (20°C), an offset that can vary within the ran-
ge -5 to +5 (offset 0 = 20°C). For the correction of the offset, refer to paragraph
"6.3 Setting the heating setpoint with an external probe
CLIMATIC CURVE CORRECTION
CORREZIONE CURVA CLIMATICA
90
80
70
60
50
40
30
+5°C
20
0°C
-5°C
10
30 25 20 15
external temperature (°C)
Temperatura esterna (°C)
NIGHT-TIME COMPENSATION (parameter 420)
If a timer is connected to the AMBIENT THERMOSTAT input, parameter 420
can be used to enable night-time compensation.
ƒ Set parameter 420 = 1
In this case, when the CONTACT is CLOSED, the heat request is made by the
flow sensor, on the basis of the outdoor temperature, to obtain a nominal am-
bient temperature on DAY level (20 °C). The OPENING OF THE CONTACT
does not produce a switch-off, but a reduction (parallel translation) of the climatic
curve on NIGHT level (16 °C).
3,0 2,5 2,0
1,5
1,0
0,8
0,6
0,4
0,2
5 0 -5 -10 -15 -20
".
10 5 0 -5 -10 -15 -20