9
Inspection and maintenance
Logano plus GB402 - Subject to technical modifications!
43
9.4
Checking the heating system operating pressure
In sealed unvented systems the pressure gauge needle
must be within the green band.
Ensure that the red pressure gauge needle is set to the
required operating pressure.
B
Check the operating pressure of the heating system.
The operating pressure is too low if the pressure gauge
needle is below the green range. Top up with water.
Fig. 42 Pressure gauge for sealed unvented systems
1
Red needle
2
Pressure gauge needle
3
Green band
B
Fill water via the on-site drain & fill valve.
B
Vent the heating system via the radiator bleed valves.
B
Check the operating pressure again.
B
Enter amount of top-up water in the operator's log.
9.5
Measuring carbon dioxide content
B
Insert the test sensor through the test port in the flue
pipe and hold it in the core gas flow.
B
Record the flue gas values.
If the CO
2
content differs by more than 0.5 % from its
set value (
Æ
Tab. 3, page 11), adjust the burner as
described from Chapter 7.10 to 7.10.2.
NOTICE:
System damage.
If the heating system is filled when hot, the
resulting temperature stresses can cause
stress cracks. The boiler will then leak.
B
Only fill the heating system when cold
(the flow temperature should not exceed
40 °C).
B
When the heating system is in
operation, never fill it via the boiler
drain & fill valve. Instead, only use the
filling valve in the heating system
pipework (return).
B
Pay attention to the water quality as
specified in the operator's log, and record
the volume and quality of fill water used.
NOTICE:
System damage due to frequent
topping up.
Depending on water quality, the heating
system may be damaged by corrosion or
limescale formation if you frequently need to
top up the water (observe the operator's log).
B
Vent the heating system during filling.
B
Check the heating system for leaks.
B
Check the function of the expansion
vessel.
Create an operating pressure of at least
1 bar.
CAUTION:
Health risk from contaminated
drinking water.
B
Observe all regulations and standards
applicable in your country regarding the
prevention of drinking water
contamination.
The operating pressure can also be checked
at the control unit via the “Info menu”
(e.g. display “P1.4” corresponds to 1.4 bar).
6 720 615 876-59.1RS
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