NCB300 Gas Condensing
The NCB300 gas condensing combi boiler is our entry model, which offers the same hot water comfort, powerful heating and flexible installation options as larger models, but in a compact design. This combination of features makes the NCB300 gas boiler an excellent choice for smaller properties where exceptional levels of reliability and DHW performance are the priority.
Technical Data
Shower rating
Heat Output
DHW
Modulation
Flue
Weight
Dimensions
ErP Efficiency
ErP Efficiency with Smart Plus (x3)
NOx Classification
NCB300 Gas Condensing
What does the fault code E302 for NCB-CE or NCB300 mean?
E302 means that the system pressure is too low and you may see that the system pressure gauge indicates that the pressure in the system is below the 1 bar pressure.
To re-pressurise the system you will find a filling loop (metal braided flexible hose) on the underside of the boiler with two tap connections at either end of the filling loop. One small blue & one small black tap handles.
The taps should be opened a quarter of a turn. Open the small black one and then open slowly the small blue one. The water will start to refill the system (water should be heard filling the system). You should see the pressure gauge rise back up between 1 bar and 1.2 bar pressure and then stop filling.
Once the pressure gauge is between 1 bar and 1.2 bar turn the taps back to the off position and the water will stop filling the system. The error code E302 will stop and the boiler will now operate. If the error code E302 is still active, fill up the system a little more but not over 1.5 bar.
(If you do fill the system too much and the pressure gauge is too high, just bleed water from a radiator until the pressure on the gauge goes down to below 1.2 bar).










