Maintenance
48
7
3. Exit menu 3 by pressing the
key until displaying the
letter "E" for exit, then press the
key.
4. The water temperature values alternate again on the
display: output, input and the difference between them.
6.6.3
How to raise/lower the DHW setpoint
The DHW setpoint determines the temperature of the DHW buff-
er tank, if there is or is not a DHW request from a switch or a
daily/weekly timer. The temperature setting is set by the TAC at
the first start-up.
By default the water setpoint is set when the external DHW re-
quest contact (COM-DHW) is closed.
To raise/lower the DHW temperature setpoint, through
the GHP10/GHP11 board, proceed as follows (see also
Paragraph 6.5
p. 45):
1. Access menu 3 parameter 227 (= DHW setpoint with
COM-DHW contact closed) with keys
and
; set
parameter 227 to the desired temperature setting.
2. If needed, also change the setting of parameter 237 (=
DHW setpoint with open COM-DHW contact) to the de-
sired temperature value.
3. Exit menu 3 by pressing the
key until displaying the
letter "E" for exit, then press the
key.
4. The water temperature values alternate again on the
display: output, input and the difference between them.
6.7
RESTARTING A LOCKED-OUT UNIT
6.7.1
Fault signals on the display
In the event of locked-out appliance, an operational code flashes
on the display (first green figure on the left, letter "u" = warning
or "E" = error).
▶
To restart the appliance you must know and perform the
procedure concerning the issue signalled and identified by
the code (Paragraph 8.1
▶
Only act if you are familiar with the issue and with the pro-
cedure (technical expertise and professional qualifications
might be required).
▶
If you do not know the code, the problem, or the procedure,
or you do not have sufficient skills, and in any case of doubt,
contact the TAC.
6.7.2
Locked-out appliance
An external intervention (reset or repair) is required due to an
appliance fault or problem with the system.
▶
A reset may be enough for a temporary and provisional fault.
▶
For a fault or breakdown, alert the maintenance technician
or TAC.
6.7.3
Reset
There are three options for resetting a fault:
1. If the appliance is connected to the OQLT021 system control-
ler, you may act through the control device, as described in
the relevant manual.
2. If a remote reset button has been provided (Paragraph
p. 34) act directly on the button.
3. Act on unlock/reset button under unit display (reference J
Figure 1.3
p. 10).
6.8
EFFICIENCY
For increased appliance efficiency:
▶
Keep the finned coil clean.
▶
Set the maximum water temperature and climatic curve at
the actual installation requirement.
▶
Reduce repeated switch-ons to the minimum (low loads).
▶
Program appliance activation for actual periods of use.
▶
Keep water and air filters on plumbing and ventilation sys-
tems clean.
▶
Deactivate or reduce the DHW request setpoint when DHW
service is not required, while still maintaining antifreeze pro-
tection in the DHW buffer tank.
7
MAINTENANCE
7.1
WARNINGS
Correct maintenance prevents problems, assures effi-
ciency and keeps running costs low.
Maintenance operations described herein may exclu-
sively be performed by the TAC or skilled maintenance
technician.
Any operation on internal components may exclusively
be performed by the TAC.
Before performing any operation, switch off the appli-
ance by means of the control device and wait for the end
of the shutdown cycle, then disconnect power and gas
supply, by acting on the electrical disconnector and gas
valve.
The efficiency checks and every other "check and
maintenance operation" (see Tables 7.1
p. 49 and
7.2
p. 49) must be performed with a frequency ac-
cording to current regulations or, if more restrictive, ac-
cording to the provisions set forth by the manufacturer,
installer or TAC.
Responsibility for efficiency checks, to be carried out for
the aims of restricting energy consumption, lies with the
system manager.
Environmental or operational heavy conditions
In environmental or operational conditions particularly
heavy (for example: heavy-duty use of the appliance,
salty environment, etc.), maintenance and cleaning op-
erations must be more frequent.
