The system can be divided into 4 zones:

Boiler zone, fitted with the following components:

·       Condensing boiler

·       Water treatment devices (dirt separator and deaerator) for the protection of the boiler and, more generally, all system components

·       Control, expansion and safety equipment

·       Charging unit with pressure reducing valve and backflow preventer

The boiler should feature set point regulation, with a temperature that can be utilised in both heating and domestic hot water production.

Conversely, the temperature of the water sent to the radiators must be regulated on the basis of the outside compensated temperature curve.

Heating system zone:

·       High efficiency tandem circulation pumps

·       Three-way regulating valve with climatic controller

Solar panels zone

This zone is essentially composed of:

·       Flat manifold or vacuum pipe type solar panels

·       Circulation unit for solar thermal systems with pump and shut-off, control, expansion and safety equipment

·       Solar circuit control unit with corresponding temperature probes

·       Solar type tank for domestic hot water production and storage

The solar circuit must be regulated so that it is activated only when:

·       The temperature of the solar panels probe by some degree exceeds (generally 5 to 8 °C), the temperature of the probe installed at the base of the tank;

·       The temperature of the probe installed at the top of the tank does not exceed the maximum safety temperature.

The dual cylinder guarantees greater efficiency in winter, thanks to the option of utilising the low temperature of the solar panel, and makes maintenance easier as it can take place without the entire system having to be switched off.

Domestic hot water production and distribution zone

This zone is essentially composed of:

·       Tank for the production and storage of domestic hot water, supplied with water from the solar cylinder

·       Regulation devices and equipment (with high flow rate thermostatic mixing valve) and for supplying domestic hot water to individual users

Domestic hot water production is controlled by a thermostat which activates circulation of the heating medium.

IMPORTANT (*): The normally closed shut-off valve is used to isolate the solar water storage during maintenance. 

Note:

The control, expansion and safety equipment must be of appropriate size to reflect the heating capacity and specific characteristics of the system, in accordance with applicable laws and regulations.

The system only operates to produce DHW. Do not oversize the tank; this will prevent water from stagnating at a temperature which encourages bacterial growth. The boiler should be set to a temperature which guarantees sufficient DHW production.