Navien NCB-700-2S+/42K, Руководство по обслуживанию

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System Details 21
CAUTION
Ensure that no cables are in the way before folding down
the PCB assembly. If the assembly is stuck, do not force
it. Doing so may damage the cables and result in serious
malfunctions. Check again to ensure that no cables or any
other parts are in the way before you proceed.
5. Loosen the screws indicated in the figure below and
connect a manometer to the pressure port. Reset the
manometer to zero before use.
Digital pressure manometer
6. Re-open the manual gas valve and check for leaks.
7. Open multiple fixtures that have high flow rates, such
as bathtub and shower taps, to ramp the boiler up to its
maximum firing rate.
8. When the boiler reaches its maximum firing rate, check
the inlet gas pressure reading on the manometer. The gas
pressure must fall within the ranges specified on page 9.
Propane Gas Connection (LPG)
●
For use with propane gas, the LPG conversion kit has to be
installed, see separate conversion instructions.
●
The LPG installation must comply to the current Gas Safety
(Installation and Use) Regulations, in accordance with BS 6891.
●
Installing of a LPG installation should only be done by a
registered LPG installer.
●
The tank must be provided with a high pressure regulator with
a minimum capacity of 24 kg/h to reduce the tank pressure
from 5 to 1.5 bar. The 1.5 bar high pressure gas line should
have a minimum diameter of 15 mm. In the high pressure gas
line a house pressure regulator must be installed.
●
When tested at the gas valve, the pressure drop from the
pressure regulator to the gas valve must not be more than
2 mbar.
●
Each gas appliance which is connected to the propane
installation must be provided with its own house pressure
regulator. The house pressure regulator is a third party part.
The house pressure regulator must have a minimum capacity
of 10 kg/h/37 mbar and a CE certification.
To measure the inlet gas pressure:
1. Shut off the manual gas valve on the gas supply line pipe.
Gas Valve
Opened Closed
2. Open a hot water tap. The boiler should turn on and the gas
in the gas supply line will be purged.
3. Leave the tap on until the boiler shuts down due to a lack of
gas supply, and then turn off the hot water tap.
4. Unfasten the 2 latches (at the top) and remove 2 screws (at
the bottom) to remove the front cover and gain access to
the internal components.