3.2.6. Verifying combustion efficiency
In order to determine combustion efficiency, the following measure
-
ments are to be performed:
- combustion air temperature
- flue gas temperature and CO
2
concentration, from the relevant
opening on the flue gas pipe.
Perform the above measurements when the boiler has reached
working temperature.
3.2.7. Gas main connection
Gas supply pipe section must be equal or larger than boiler’s.
The applicable section of the pipe depends on its length, path, and
flow rate. Its section is to be calculated.
Refer to applicable installation standards and laws. They shall
be considered as incorporated in full in this manual.
An internal, brand new gas supply network, before supplying
any gas or being connected to the gas meter, is to checked
for leaks.
When sections of the network are concealed, the leak test
must be carried out prior to covering the pipes.
The leak test must not be conducted using fuel gas: use air
or nitrogen.
When gas is flowing through the pipes, gas leaks should ne
-
ver be detected using an open flame device.
Use appropriate products, readily available on the market.
3.2.8. Power main connection
The boiler is to be connected to a 230V-50Hz power main supply
via a triple-poled wiring (not included).
The wires are to be connected to position 5 (EARTH), 6 (PHASE),
and 7 (NEUTRAL) of M terminal board in picture 9 (BTN E and
BTFS E models), or to position 12 (EARTH), 13 (PHASE), and 14
(NEUTRAL) of M terminal board in picture 10 (BTN E V and BTFS
E V models).
Verify phase, neutral and ground connections are correctly perfor-
med, following the instructions in this manual.
When installing the boiler, comply with applicable standards which
shall be considered fully incorporated to this manual.
A bipolar switch, with 3 mm minimum distance between the con-
tacts, in an easy to reach position, must be installed externally
to the boiler to enable interruption of power supply and to ensure
maintenance operations to be carried out safely.
The power main line to the boiler must be protected by a differential
thermal-magnetic switch with the adequate interruption power.
Power mains is to be properly earthed.
The above instruction is an indispensable safety requirement and
is to be verified prior to operating the boiler; in case of doubt, ask
for a professionally qualified technician to check the electrical sy
-
stem.
The manufacturer shall not be held liable for damage or injury cau-
sed by failure to properly earth the power main.
Gas lines, DHW and CH pipes are not suitable for earthing purpo-
ses.
3.2.9. Hydraulic connections
Before connecting the boiler it is advisable to clean the pipes in
order to remove any alien material that could damage boiler com-
ponents such as pump and heat exchanger.
CENTRAL HEATING
Central heating flow and return must be connected to their relevant
1” connections, marked M and R in pic. 5 and 5B).
When size dimensioning central heating pipes, it is necessary to
consider load losses induced by radiators, presence of thermosta-
tic valves, radiator cut-off valves and general configuration of the
central heating system.
It is advisable the discharge of the safety valve to be conveyed
into the sewer.
If this precaution is not taken, activation of the safety valve
may result in flooding of the room where the boiler is instal
-
led.
The Manufacturer shall not be held responsible for damage
caused by omission of the above mentioned technical precau-
tion.
DOMESTIC HOT WATER
DHW flow and water main inlet pipes must be connected to the their
3/4” connections, marked C and F (pic. 5A and pic. 5B).
Hardness of water increases frequency of service to the secondary
plate heat exchanger.
WARNING
Should water hardness be far above average, it is advisable to
install a water softener device.
Water showing 20°F or more hardness should be treated.
WARNING
Due to its pH value, water supplied from normal water softe-
ners may not be compatible with some components of the hea-
ting system.
3.2.10. Room thermostat connection
The boiler can be connected to a room thermostat: its contacts
must be properly sized in consideration of a 5 mA load at 24
Vdc.
Room thermostat wirings must be connected to positions 1 and 2
of M terminal board shown in pic. 9 (BTN E and BTFS E models),
after removing the jumper supplied as standard to the boiler.
Room thermostat wires are NOT to be grouped together with power
main supply cables.
BTN E V and BTFS E V models can be connected to two room
thermostats: one managing a high temperature CH area to no. 8
and no. 9 positions of M terminal board, one managing a low tem-
perature CH area to no. 6 and no. 7 positions of M terminal board.
3.2.11. Adjustable by-pass
The boiler is equipped by an adjustable by-pass (located on the
three-way motorized valve hydraulic assembly). By-pass operation
can also be inhibited.
Pic. 8A shows the adjusting by-pass screw, set for by-pass opera-
tion preclusion, pic. 8B shows the adjusting by-pass screw set for
by-pass operation.
pic. 8
A
B
Closed
by-pass
Open
by-pass
17