Draining The Product; Checking The Pre-Charge Pressure Of The Expansion Vessel; Completing Inspection And Maintenance Work; Troubleshooting - Vaillant ecoFIT sustain 800 Series Installation And Maintenance Instructions Manual

12.14 Draining the product

1. Close the service valves of the product.
2. Start check programme P.05.
Overview of the check programmes (→ Page 24)
3. Open the drain valves.
12.15 Checking the pre-charge pressure of the
expansion vessel
1. Drain the product. (→ Page 34)
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)
▶
Top up the expansion vessel in accordance with the
static height of the heating installation, ideally with ni-
trogen, otherwise with air. Ensure that the drain valve is
open when topping up.
3. If water escapes from the valve of the expansion
vessel, you must replace the expansion vessel
(→ Page 36).
4. Fill and purge the heating installation. (→ Page 26)
12.16 Completing inspection and maintenance
work
1. Check the gas connection pressure (gas flow pressure).
(→ Page 27)
2. Check the CO₂ content. (→ Page 28)
3. Set the maintenance interval.
4. Check the product for tightness. (→ Page 29)
5. Install the front casing. (→ Page 16)
6. Fill out the relevant Service Record section in the
Benchmark Checklist located at the rear of this
document.

13 Troubleshooting

13.1

Eliminating faults

▶
If fault messages (F.xx) appear, eliminate the fault after
referring to the table in the appendix or using the check
programmes. (→ Page 24)
Overview of fault codes (→ Page 44)
If several faults occur at the same time, the display shows
the corresponding fault messages for two seconds each in
alternation.
▶
Press (max. three times) to restart the product.
▶
If you are unable to eliminate the fault and the fault re-
curs despite reset attempts, contact customer service.
34
13.2

Calling up and clearing the fault memory

The last 10 fault messages are stored in the fault memory.
▶
Call up the installer level. (→ Page 24)
▶
Navigate to the fault codes.
◁
The number of faults that have occurred is shown in
the display and the faults that are currently called up
are displayed with their fault numbers F.xx.
▶
Press or to call up individual fault messages.
▶
To delete the entire fault list, navigate to diagnostics code
D.094 in the installer level.
▶
Set the diagnostics code to 1, and confirm by pressing
.
13.3

Resetting parameters to factory settings

1. Navigate to diagnostics code D.096 in the installer level.
2. Set the diagnostics code to 1, and confirm by pressing
.
13.4

Preparing the repair work

1. Switch off the product.
2. Disconnect the product from the electrical installation.
3. Remove the front casing.
4. Close the gas stopcock.
5. Close the service valves in the heating flow and in the
heating return.
6. Close the service valve in the cold water pipe.
7. Drain the product if you want to replace water-bearing
components of the product.
8. Ensure that water does not drip on live components
(e.g. the electronics box).
9. Use only new seals and O-rings. Do not use any addi-
tional sealing materials.
13.4.1 Procuring spare parts
The original components of the product were also certified
by the manufacturer as part of the declaration of conformity.
If you use other, non-certified or unauthorised parts during
maintenance or repair work, this may void the conformity of
the product and it will therefore no longer comply with the
applicable standards.
We strongly recommend that you use original spare parts
from the manufacturer as this guarantees fault-free and safe
operation of the product. To receive information about the
available original spare parts, contact the contact address
provided on the back page of these instructions.
▶
If you require spare parts for maintenance or repair
work, use only the spare parts that are permitted for the
product.
Installation and maintenance instructions ecoFIT sustain 0020230529_05