35
Flue gas analysis
The boiler is equipped with two pressure
access points, from which you can observe
the temperature of the combustion gas,
flammable air and the mixture of oxygen and
carbon dioxide outside the top of flue pipe
enter into the pressure holes, unscrew fixed
flue pipe cap and sealing gasket
When conducting flue gas analysis or power
adjustment, the CO
2
of the flue gas and
revolving speed of the fan should correspond
with the following table:
ROC COMBI HE 28
Air speed (rpm)
6200-6600
1700-2400
CO
2
%
9.2±0.2
8.8±0.2
Power
Max. power
Min. power
ROC COMBI HE 40
Air speed (rpm)
7200-7800
1700-2400
CO
2
%
9.2±0.2
8.8±0.2
Power
Max. power
Min. power
Warning!
It is forbid to operate power adjustments
when the gas inlet pressure is not between
17-25. The tightness of all the control points
must be checked after adjusting the power.
Capacity adjustment
1). Preparation: unscrew the gas valve inlet
and connect the pressure gauge (picture-C)
and unscrew plug A with 6.5mm flat
screwdriver which is covering B (see below
pictures) .
2.) Gas pressure test, Turn on the boiler,
open the hot water to maximum water flow.
Enter ECS menu (see page 32) select “Pr09
parameter 04”, test the gas inlet pressure, and
the pressure should be between 17~25 mbar.