120
Gas/air ratio
With every service check and/or maintenance of the boiler always check the gas/air ratio by measuring the CO
2
/
O
2
percentage (flue gas) at the maximum and minimum load of the boiler. If necessary, adjust these values. See
for information chapter “Adjusting and setting the boiler” chapter 18.
Pump (supplied separated from the boiler)
Check the electrical parts and the motor of the pump for a correct functioning. The pump must generate a sufficient
water flow over the (heat exchanger of) the boiler. When the pump produces noise, is operational for more than
five years or has signs of water leakage it is recommended to replace the pump as a precaution.
When faults and abnormalities are found by the service technician during service and
maintenance and these are not repairable, this information should be reported to the owner/end-
user of the installation. Also, the owner/end-user should be advised how to fix these faults and
these faults should be reported in the service report / log file of the boiler.
During service and maintenance, the gas, supply air, flue gas and condensate connections are
disconnected, checked and replaced. Make sure that all these components are mounted
correctly before commissioning the boiler again.
Cleaning the combustion chamber and heat exchanger with acid or alkali products is prohibited.
19.2.1 M
OUNTING THE BURNER DOOR
IMPORTANT:
Before mounting the burner door, make sure that its
gaskets and insulation are in excellent shape.
If any signs of damage or ageing are present, these
parts must be replaced.
The burner door must be mounted back on the heat
exchanger as follows:
- Place the burner door with its holes over the six
threaded studs.
Careful! When handling too rough or misplacing
the holes over the threaded studs, the burner door
insulation and/or gaskets can be damaged.
Ensure that the door is well positioned with respect
to the threaded studs, before pushing it onto the
exchanger.
- Keep the burner door firmly in place by pushing the
gas/air premix manifold with one hand at the
middle at point A.
- Hand tighten the flange nuts with the other hand as
far as possible onto the threaded studs.
Now the burner door is in place and the nuts can be
tightened with a torque wrench.
- Tighten the nuts in the order given in the
picture
- The specified torque value for tightening the
burner door flange nuts is
8 Nm (70.8 inch
lbs)
Tighten in given order.
Torque Value = 8 Nm
WARNING
1
6
2
3
4
5
A
Summary of Contents for S-CBX 105
Page 2: ......
Page 40: ...40 9 10 Flue Terminal Positioning ...
Page 42: ...42 9 11 1 FIGURE 12 LINE G ...
Page 55: ...55 11 5 Ladder Logic Diagram ...
Page 56: ...56 11 6 Electrical schematics ...
Page 57: ...57 ...
Page 137: ......