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About the Boiler 17
Exhaust
Gas
Blow Fan
Air
I
n
Air
I
n
I
gnitor
Gas
Valve
Gas
I
nlet
DHW
O
ut
Cold
Water
I
n
Three
-way
Valve
DHW Heat
Exchanger
Circulation
Pu
m
p
Heat Exchanger
2.6.3 Operating in DHW Mode
To operate in DHW
m
ode, press the DHW button on the front
panel and select a DHW te
m
perature setpoint higher than
current DHW te
m
perature.
1. When a hot water tap is turned on in the ho
m
e, the boiler
flow
m
eter detects DHW de
m
and, the 3-way valve goes
to DHW
m
ode and the circulation pu
m
p starts up, which
m
akes the water in the boiler pri
m
ary circuit flow through
the DHW heat exchanger, producing instant hot water.
2. The electronic control
m
odulates the burner output in
order to constantly produce hot water at the te
m
perature
re
q
uired.
3. When there is no further DHW de
m
and, the burner switches
off and the 3-way valve re
m
ains in DHW
m
ode position
during a wait ti
m
e (5
m
inutes by default), so that it can work
m
ore efficiently and provide
m
ore flexibility if the taps are
continuously turned on and off.
4. When the wait ti
m
e has elapsed, the 3-way valve returns to
the Heating
m
ode position and the boiler is ready to provide
heating.
Note
Ɣ
DHW priority: Whenever a hot water tap is turned
on in the ho
m
e, the boiler begins to run in DHW
m
ode and the heating function is deactivated until
all the taps are turned off again.
Ɣ
When the boiler water pressure drops below 0.4 bar
the auto
m
atic fill function is activated.
Summary of Contents for NCB-24LDWE
Page 65: ...Appendices 65 12 4 Ladder Diagram 3 15A...
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