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Instructions for the installer
3.9 Solar collector probe installation
The boiler is equipped with a solar plant temperature probe that must be installed by a qualified engineer.
The probe must be installed between the boiler and the solar field. If the supplied cable is not long enough, add an extension by using a 2-wire
shielded outdoor cable.
The two probe cables must be connected to pins 11 and 12 of the boiler electronic board (see par.
Wiring diagrams
on page
72
). The probe
sensor must be installed on the solar field to detect the output temperature of the same (see solar collector instructions).
3.10 Connection to electrical mains
The boiler is supplied with a three-poled power cable, already connected to the electronic board and it is provided with a safety clamp.
The boiler is to be connected to a 230V-50Hz electrical power supply.
When connecting it to power mains, follow correct phase / neutral polarity sequence.
Installation standards must be complied with and they are herein considered as entirely transcribed.
An easily accessible two-poled switch, with a minimum 3 mm distance between contacts, is to be installed ahead of the boiler. The switch is to
allow power supply cut-off in order to safely perform maintenance and service procedures.
Power supply to the boiler must be fitted with a residual-current circuit breaker having suitable disconnection capacity. Electric power supply
must be properly earthed.
The above mentioned safety measure must be verified. If in doubt, ask a qualified technician to thoroughly check the power network.
WARNING
The manufacturer cannot be held responsible for any damage caused by failure to earth the system correctly: gas, water, or CH
system pipes are not suitable for grounding power networks.
3.10.1 Selecting the operating range in heating mode
Heating water temperature adjustment range depends on the selected operating range.:
• standard range:
from 20°C to 78°C (pressing CH +/-);
• reduced range: from 20°C to 45°C (pressing CH +/-).
The standard range is active with curves P10 ≥1, while the reduced range is active with curves P10 <1.
The two ranges can also be selected even with the external probe disconnected.
The waiting time between one boiler ignition and the following one, used to prevent boiler frequent turning on and off is 4 minutes for both
ranges, and can be edited with the parameter P11.
If system water temperature decreases below a certain value, the waiting time is reset and the boiler re-ignited, as shown in the following
table:
Selected range
Re-ignition temperature
Standard range
< 40°C (P27)
Reduced range
< 20°C
Tab. 9 Boiler re-ignition temperature
Operation range selection is to be implemented by a installer or a qualified Service Centre.
3.11 Connection to ambient thermostat (optional)
The boiler is designed to be connected to an ambient thermostat (optional, not compulsory).
Ambient thermostat contacts must be properly sized in compliance with a load of 5 mA at 24 Vdc.
The ambient thermostat cables must be connected to terminals 1 and 2 of the electronic board (see par.
Wiring diagrams
on page
72
) after
having eliminated the jumper supplied as a standard with the boiler.
The ambient thermostat cables are not to be grouped together in the same sheath as power mains supply cables.
