M
aintaining the Boiler 51
11.4 Protecting the Boiler from Freezing
CAUTION
Da
m
age due to freezing is not covered by the Navien li
m
ited
warranty.
The boiler is designed for indoor installation only.
I
f the boiler is connected to a circuit that could freeze, the circuit
pipes
m
ust be suitably insulated. All pipes installed outdoors
m
ust be insulated according to applicable legislation.
The boiler electronic control includes an freeze protection
function that prevents the boiler fro
m
freezing in very cold
weather.
I
t re
m
ains on standby and takes priority over all other
boiler functions while the boiler is connected to the electrical
m
ains and gas supply, i.e. it re
m
ains enabled even when the
boiler is in standby position.
To ensure that the boiler does not freeze, follow these
guidelines:
Ɣ
Do not unplug the power supply cord,
except for routine
m
aintenance. The boiler has a freeze protection function that
re
q
uires electricity. The freeze protection function will operate
regardless of whether or not the power is turned on or off, as
long as the electric supply is still connected.
Ɣ
Do not close the gas valve,
except for routine
m
aintenance,
as this will li
m
it additional freeze protection.
Ɣ
If the boiler will not be used for an extended period, drain
the boiler.
I
f the power or gas supplies
m
ust be disconnected for an
extended period, drain the boiler. Freezing da
m
age
m
ay occur
if there is water re
m
ained in the boiler in cold weather.
6. Close off any heating zones that do not re
q
uire draining and
open a purge valve to drain the space heating side.
O
pen
all do
m
estic hot water taps co
m
pletely to drain the water
heating side. The water that re
m
ains in the plu
m
bing lines
will drain out.
Pu
m
p Drain Plug
7.
O
pen the pu
m
p drain plug.
8. Allow the residual water to drain fro
m
the boiler.
9. When the water is co
m
pletely drained, reinsert the return
adapter filter and close the pu
m
p drain plug.
10. To refill the boiler follow the steps of “Draining the Boiler” in
reverse.
11.3 Cleaning the Return Adapter Filter
To clean the filter:
1. Drain the boiler. Refer to “11.2 Draining the Boiler” on
page 50.
2. Re
m
ove the filter and rinse it with clean running water
(cold).
I
f necessary, scrub it clean with a brush.
3. Reinsert and tighten the filter.
4. Fill the boiler and check for proper operation.
Summary of Contents for NCB-24LDWE
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Page 69: ...Memo...
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