Intergas Heating Ltd
41
10.8.3
Correction gas air ratio on minimum power
Before the correction of the gas air ratio on minimum output the measurement of the maximum
output must be completed. The measured O
2
or CO
2
value at maximum output is important for
determining the correct value for the measurement at minimum output. See § 10.8.1 and
§ 10.8.2 for measuring at maximum output.
1.
Remove the cover cap (A) on the gas valve so setting screw B will become attainable.
2.
Activate the test program for minimum output by simultaneously pressing the
buttons
and . A capital
L
appears in service display.
3.
Wait until the reading of the analyser is stable (min. 3 minutes).
4.
Measure the O2(L) or CO2(L) value
5.
Set, using adjustment screw B de correct value for O2(L) or CO2(L).
See table 5a or 5b for the correct value
•
Choose the correct table (4a and 5a is for natural gas, 4b
and 5b is for Propane).
•
The value measured at maximum output as noted during the
measurement on maximum output (CO2(H) or O2(H) )
Turning clockwise of the adjustment screw will raise the CO2
value and lower the O2 value. Turing anti clockwise will raise
the O2 value and lower the CO2 value.
•
Change the setting in small steps and wait until the reading
is stable before continue.
Table 4a: Determining the correct setting of O
2
at minimum output for natural gas G20
(open casing)
Natural gas G20 (20 mBar)
Measured value am maximim power
(See § 10.8.1)
Prescribed value at minimum power
(= 0.5 x O
2
(H) + 3.0)
O
2
(H) [%]
O
2
(L) [%]
5.60
5.80 ±0.2
5.30
5.65 ±0.2
5.00
5.50 ±0.2
4.70
5.35 ±0.2
4.40
5.20 ±0.2
4.10
5.05 ±0.2
3.85
4.90 ±0.2
Table 4b: Determining the correct setting of O
2
at minimum output for propane G31
(open casing)
Propane 3P G31 (37 mBar)
Measured value am maximim power
(See § 10.8.1)
Prescribed value at minimum power
(= O
2
(H) + 0.5)
O
2
(H) [%]
O
2
(L) [%]
6.05
6.55 ±0.2
5.70
6.20 ±0.2
5.40
5.90 ±0.2
5.10
5.60 ±0.2
4.80
5.30 ±0.2
4.50
5.00 ±0.2
03010102
A
B
