n
7.8.6
7.9
7.9.1
7.9.2
7.9.2.1
c
74
3.
The electrical section is now visible.
4.
Remove the black caps from the measurement point of the pressure switch.
5.
Connect the + of the pressure gauge to the H of the measurement point of the
pressure switch.
6.
Connect the - of the pressure gauge to the L of the measurement point of the
pressure switch.
7.
Zero the pressure gauge.
8.
Start the appliance (see section 4.1).
9.
The appliance will now run the heating cycle (see section 4.1.1).
10.
Read the pressure from the meter at the moment when the appliance switches from
PRE PURGE to PRESSURE SWITCH. At this point, the appliance's display will show:
11.
Check whether the measured value matches the value from the table (see section
12.1).
Note
If the message PRESSURE SWITCH does not appear, there is a fault. This must be
resolved first by a qualified service engineer.
12.
Shut off the gas supply.
13.
Disconnect the pressure gauge.
14.
Put the two black caps back on the pressure switch.
15.
Replace the covers.
Turn on the water heater
Refer to the procedure in the user part to Turn on the water heater (see section 4.1).
Decommisioning
To decommission the water heater:
1.
Turn off the water heater (see section 7.9.1)
2.
Drain the water heater
Turn off the water heater
Refer to the procedure in the user part to Turn off the water heater (see section 4.2) and
isolate the water heater from the mains power supply.
Draining
Draining unvented installations
Some service activities require the water heater to be drained. The procedure is as
follows:
1.
Activate the MENU with [
2.
Position the cursor in front of OFF.
3.
Confirm OFF with [ENTER].
4.
Wait until the fan has stopped. The
Caution
Failure to wait until the fan stops can cause damage to the water heater.
].
icon is then dimmed.
Installation, Maintenance and Service part