12.14 Draining The Product; Checking The Admission Pressure Of The Expansion Vessel; Completing Inspection And Maintenance Work; 12.17 Checking The Product For Leak-Tightness - Vaillant ecoTEC sustain 24 Installation And Maintenance Instructions Manual

7. Check that the sealing ring in the air intake pipe is posi-
tioned correctly in the seal seat.
8. Reconnect the air intake pipe to the intake stub.
9. Secure the air intake pipe with the retaining screw.
10. Check the gas flow pressure.

12.14 Draining the product

1. Close the service valves of the product.
2. Start check programme P.06 (prioritising diverter valve
mid-position).
3. Open the draining cock.
4. Make sure that the cap of the automatic air vent on
the internal pump is open so that the product can be
drained fully.
12.15 Checking the admission pressure of the
expansion vessel
1. Drain the product. (→ Page 39)
2. Measure the pre-charge pressure of the expansion ves-
sel at the vessel valve.
Condition: Pre-charge pressure < 0.075 MPa (0.75 bar)
▶
Fill the expansion vessel in accordance with the static
height of the heating installation; ideally with nitrogen,
otherwise with air.
▶
Ensure that the drain valve is open when filling.
3. If water escapes from the valve of the expansion ves-
sel, replace the expansion vessel (→ Page 41).
4. Fill and purge the heating installation. (→ Page 29)
12.16 Completing inspection and maintenance
work
▶
Start a test operation after the maintenance.
▶
Check the heating mode and, if required, the domestic
hot water generation (if available).
▶
Check the gas connection pressure (gas flow pressure).
(→ Page 30)
▶
Check the CO₂ content. (→ Page 31)
▶
If required, reset the maintenance interval. (→ Page 33)
▶
Install the front casing.
▶
Fill out the relevant Service Record section in the Bench-
mark Checklist.

12.17 Checking the product for leak-tightness

▶
Check that the product is leak-tight. (→ Page 32)
0020253094_05 ecoTEC sustain Installation and maintenance instructions

13 Troubleshooting

13.1

Checking service messages

appears, for example, if you have set a maintenance inter-
val and this has passed or if a service message has been is-
sued. The product is not in fault mode.
▶
Call up the Live Monitor. (→ Page 26)
Condition: S.46 is displayed.
The product is in Comfort protection mode. The product con-
tinues to run with restricted comfort after it has detected a
fault.
▶
To establish whether or not a component is defective,
read the fault memory. (→ Page 39)
Note
If no fault message is present, the product will
automatically switch back to normal operating
mode after a certain time.
13.2

Rectifying faults

▶
If fault codes (F.XX) are present, refer to the table in the
appendix for advice or use the check programme(s).
Overview of fault codes (→ Page 50)
Check programmes – Overview (→ Page 45)
If several faults occur at the same time, the fault codes are
shown alternately on the display.
Resetting the product:
▶
Press and hold the button for more than three
seconds.
◁
The product restarts.
▶
If you are unable to clear the fault code and it reappears
despite several fault clearance attempts, contact cus-
tomer service.
13.3

Calling up the fault memory

The last ten fault codes are stored in the fault memory.
▶
Call up the installer level. (→ Page 26)
◁
d.-- is shown in the display.
▶
Press the button 2 times.
◁
F.XX is shown in the display.
▶
Press the and buttons to call up the fault codes.
Overview of fault codes (→ Page 50)
◁
The fault code and the time of occurrence are shown
alternately on the display.
▶
Press .
◁
The display switches to the basic display.
39