Nobel 1000lt, Инструкция по установке, эксплуатации и обслуживанию

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HYDRAULIC UNIT
It contains all the basic accessories required for the connection of the collectors to the buffer.
y
For the connection of the hydraulic unit to the solar circuit (collectors, system heat exchanger to the inferior part
of the buffer) please refer to the hydraulic diagram of solar systems.
y
The connection of the expansion vessel to the safety valve of the solar hydraulic unit should have a maximum
length of 2 meters, with no bends and no air accumulation points. The union nut should have a diameter of 3/4’’.
y
After having connected the hydraulic unit, the closed loop should be cleaned. System cleaning is carried out with
water for 15 minutes, by isolating the circulation pump with the two valves before and after, and by opening the
two filling/evacuation valves. The valves for the connection of plastic pipes are male.
y
Prior to filling the closed loop with the anti-freeze liquid it is necessary to check the sealing of all the connections.
During the cleaning, for example, you can shut one of the two filling/evacuation valves and use a compression
pump or water compression from the network to raise the pressure of the circuit to 5 bars for 15 minutes.
ATTENTION!
The expansion tank has to be isolated to avoid surpassing the maximum operating pressure.
y
The mixing of the anti-freeze liquid must be carried out prior to the filling and at a ratio suitable to resist the
minimum ambient temperature at which it is going to operate.
y
System filling may be executed either from the upper side of the collector by gravity or through the compression
pump from the hydraulic unit. Operating pressure from 1.5 to 3 bars can be executed with pump filling or with the
water compression from the network. Constantly check all ventilation points as you fill the circuit.
y
All installations and the relative attachments have to conform to the current local regulations (electrical, hydraulic,
building, sanitary etc.) in force.
y
It is recommended to place a vessel under the hydraulic unit of a capacity suitable to collect the anti-freeze
liquid that may run from the security valve. The presence of this vessel is particularly useful during the filling and
ventilation phases or during hydraulic testing, as the valve opens at 6 bar.
CLOSED LOOP PIPING
y
All pipes starting from and resulting to collectors must by appropriately insulated in order to resist to temperatures
from -30°C to +120°C. It is also necessary to protect insulating material from UV rays.
y
The thickness of insulation depends on the local climate conditions.
y
To minimize heat losses, the distance between collectors and the buffer heat exchanger must be the smallest
possible.
y
Avoid the concentration of air. If this is not possible, the installation of an automatic ventilator at the air accumulation
point. concentration is necessary.
y
Pipes diameter must be from Ø18mm to Ø22mm for distances up to 20 meters and Ø15mm for distances up to
12 meters.
y
All the union nuts must resist compression 6 bar and temperatures from -30°C to +200°C.
y
The annual check of the equipment and its connections is mandatory.
HYDRAULIC UNIT DESCRIPTION
Pumping, regulating, venting unit for forced circulation solar systems. In the hydraulic system, hydraulic balancing,
flow measurement and venting can be performed directly in the station. The built-in SETTER Inline PF valve allows
the required quantity of liquid in the primary circuit to be exactly and simply set and checked. The continuous venting
system meets the most demanding requirements and keeps the system free of air. Systems which are air-free
and correctly balanced hydraulically guarantee optimal energy efficiency, and are thus more cost-effective in the
framework of the energy-saving directives laid down by law.
Using the scale, which is pre-calibrated for glycol, the technician can set and check the exact flow-rate values on-site.
Neither training courses nor expensive measuring devices are required. Installation and venting can be carried out
by one person working unaided.