Mynute Boiler
19
3.5 Fumes exhaustion and air suction (Mynute Boiler
B.A.I.)
Observe applic
able legislation regarding flue gas exhaustion.
The exhaust system must be made using rigid ducting, the joints
between elements must be hermetically sealed and all components
must be resistant to heat, condensation and mechanical stress and
vibration.
Non insulated outlet pipes are potential sources of danger.
The apertures for the combustion air must be realised in compli-
ance with applicable legislation. If condensation forms, the exhaust
duct must be insulated.
Figure 12 shows a top-down view of the boiler with the dimensions
for the flue gas exhaust outlet.
Flue gas safety system
The boiler features a system monitoring that flue gases are cor
-
rectly exhausted which arrests the boiler in the event of a fault:
flue gas thermostat, fig. 11b. To restore normal operation, turn the
function selector to
(3 fig.1a), wait a few seconds, then turn the
function selector into the desired position.
If the fault persists, call a qualified technical from the Technical
Support Service. The flue gas exhaustion monitoring system must
never be bypassed or rendered inoperable. Use only original re
-
placement parts when replacing the whole system or faulty system
components.
3.6 Filling the heating and DHW systems (fig. 15)
Turning off the storage boiler drain valve (E)
a) DHW system:
- open the cold water tap to fill up the water tank
- open the hot water to check the water tank filled up and wait until
the water discharge
b) Heating system:
- giving two or three turns to the cap of the automatic air vent valve
(A) to open it
- making sure the cold water tap is open
- opening the filling tap (B) until the pressure measured by the
hydrometer is between 1 and 1,5 bar
- Close the filling tap after filling it up (B)
The boiler is equipped with an efficient air separator so that there is
no need to do anything manually.
3.7
Empty the
heating
system
- Switching off the boiler
- close the on-off taps of the heating and domestic hot water sys
-
tem
- open the automatic air vent valves (A-C)
- loosening the valve to empty boiler (D)
- emptying out the bottom parts of the system
3.8 DHW system emptying
The hot water system must be emptied every time there is risk of
freezing by:
- turning off the tap at the mains
- unscrew the cap on the hose adapter
- connect a plastic hose to the hose adapter of the storage boiler
drain valve (E)
- open the valve drain device
- turning on all the hot and cold taps
- emptying out the bottom parts
4 - IGNITION AND OPERATION
4.1 Preliminary checks
First ignition is carried out by competent personnel from an autho
-
rised Technical Assistance Service Beretta.
Before starting up the boiler, check:
a) that the supply networks data (electric, water, gas) corresponds
to the label data
b) that piping leaving the boiler is covered by thermal insulation
sheath
c) that flue gas extraction and air suction pipes work correctly
d) that conditions for regular maintenance are guaranteed if the
boiler is placed inside or between furniture
e) the seal of the fuel adduction system
f) that fuel capacity corresponds to values requested by the boiler
g) that the fuel supply system has the correct capacity for the nec
-
essary capacity to the boiler and that it has all the safety and
control devices prescribed by current regulations.
4.2 Appliance ignition
To start-up the boiler it is necessary to carry out the following op
-
erations:
- power the boiler
- open the gas tap present in the system to allow fuel flow
- turn the mode selector (3 - fig. 1a) to the desired position:
Summer mode:
turning the selector to the symbol summer (fig.
2a) the traditional function of only domestic hot water is activated
and the boiler supplies water at the temperature set on the external
storage tank. If there is a domestic hot water request the digital dis-
play shows the hot water system temperature, the icon to indicate
the hot water supply and the flame icon
Winter mode:
by turning the mode selector within the area marked
+ and - (fig. 3a), the boiler provides domestic hot water and heat
-
ing. If there is a heat request, the boiler switches on and the digital
monitor indicates the heating water temperature, the icon to indi-
cate heating and the flame icon (fig. 4a). If there is a domestic hot
water request, the boiler switches on and the digital display shows
the hot water system temperature, the icon to indicate the hot water
supply and the flame icon (fig. 5a)
Adjustment of domestic hot water temperature
To adjust domestic water temperature (bathrooms, showers, kitch-
en, etc.), turn the knob with symbol
(fig. 3a) within the area
and -.
The boiler is standby status until, after a heat request, the burner
switches on and the digital display shows the hot water system tem
-
perature, the icon to indicate the hot water supply and the flame icon.
The boiler will be in function until the adjusted temperature is
reached, afterwards it will be in “standby” again.
Environment Automatic Adjustment System Function
(S.A.R.A.) fig. 7a
By setting the heating water temperature selector to the area
marked by AUTO - temperature value from 55 to 65°C - the
S.A.R.A. self-adjusting system is activated: the boiler varies the
delivery temperature according to the closing signal of the room
thermostat. When the temperature set with the heating water tem-
perature selector is reached, a 20 minutes count begins. If during
this period the room thermostat still requests heat, the value of the
set temperature automatically increases by 5 °C.
When the new value is reached, other 20 minutes count begins.
If during this period the room thermostat still requests heat, the
value of the set temperature automatically increases by 5 °C.
This new temperature value is the result of the temperature set
manually with the heating water temperature selector and the in
-
crease of +10 °C of the S.A.R.A function. After the second cycle the
temperature value should be kept at the set value +10°C until the
request of the room thermostat is satisfied.
Anti-legionellosis function
Legionellosis is an illness that can be caught by breathing in small
drops of water (aerosol) containing the legionellosis bacillus (this
bacterium is found in rivers and lakes all over the world).
The bacterium can be eliminated by heating the storage water to a
temperature of over 50/55 °C.
At least every 2/3 days, therefore, the domestic hot water tempera
-
ture selector (knob with symbol - fig. 8a) should be moved to
maximum temperature in order to heat the water in the storage
boiler to 60°C and remain at this temperature for at least 5 minutes.
4.3 Switching off
Temporary switching off
In case of absence for short periods of time, set the mode selector
(3 - fig. 1a) to (OFF).
In this way (leaving the electricity and fuel supplies enabled), the
boiler is protected by the following systems:
- Anti-frost device: when the temperature of the water in the boiler
falls below 5°C, the circulator and, if necessary, the burner are
activated at minimum output levels to bring the water tempera-
