Morco 24CPM User Instructions And Installation Manual page 32

7.3 Gas Valve Adjustment
• Connect the flue gas analyser to the sampling point which is located on the turret
of the air/flue system
• Operate the boiler at maximum load (see section 7.4 Service Mode).
• Be sure that boiler is running at maximum load (---+ maximum fan speed).
• Wait approximately 4 minutes for the stabilisation of the values.
• Check the C02 value against the Setting Values Table below
• If the C02 value is not in the range (±0.2), gas valve adjustment is necessary.
• Turn the flow adjustment screw (see figure below) with 2.5 mm allen key counter-
clockwise (in direction +ve) to increase or clockwise (in direction -ve) to decrease
gas flow (C02 value) to the burner.
• Adjust the required C02 value (±0.1) according to the setting values table.
• Wait for the stabilization of the values
• Operate the boiler at minimum load (see section 7.4, Service Mode).
• Be sure that boiler is running at minimum load (---+minimum fan speed).
• Wait approximately 4 minutes for the stabilization of the values.
• Check the C02 value against the Setting Values Table below
• If the C02 value is not in the range (±0.2) gas valve adjustment is necessary.
• Turn the offset adjustment screw with 2.5 mm allen key clockwise (in direction
+ve) to increase or counter-clockwise (in direction -ve) to decrease minimum
C02 value.
• Wait for the stabilization of the values.
• Recheck the values at maximum load and minimum load because each
adjustment changes the previous setting value (See the flow adjustment and
offset adjustment graphs below.
Setting Values
Boiler Model
Natural Gas Propane
Fan Speed (rpm) C02 (%) 02(%) Fan Speed (rpm) C02 (%)
Morco24CPM
1620 8,7 (±0,1) 5,6 (±0,2) 1860
10,0 (±0,1)
4680
9,3 (±0,1) 4,5 (±0,2)
4440
10,8 (±0,1)
Morco 30CPM
1620 8,5 (±0,1) 6,1 (±0,2) 1860
9,7 (±0,1)
4800 9,0 (±0,1) 5,1 (±0,2) 4440
10,8 (±0,1)
32
02(%)
5,7 (±0,2)
4,4 (±0,2)
6,2 (±0,2)
4,4 (±0,2)