Biodom 27 A - Page 42

Biodom 27 A | instructions for use, maintenance and installation | March 2019
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• When connecting the boiler Biodom 27 A to central heating system you must use mechanical
elements, which prevent uncontrolled circulation of hot heating water through the boiler (grav-
ity block, spring non-return valve, solenoid zone valve, electromotor zone valve...). goal of pro-
tection is to ensure amount of heating water flow through the boiler (minimal flow through
the boiler must be over 300 l/h).
• When distribution of heating water is regulated by three-way mix valve (floor heating, weather
controlled regulation, where water flow on boiler heating loop is reduced), the system is exe-
cuted with fitted hydraulic switch and pump on primary-boiler heating loop, pump on boiler
heating loop must be controlled by boiler regulation, which already has a factory produced
electrical connection for pump.
• When a three-way mix valve is used (for floor or radiator heating, only in case of only one
mixing heating loop), connection of boiler Biodom 27 A is always executed according to scheme
nr. 3, where a hydraulic switch and a pump are built into the installation on heating cycle with
non-return valve (pump is connected to black cable from combustion device).
• Flue connection must executed in accordance with instruction limiting maximum length of con-
nection pipe Ø 80 (5 m) and that 90-degree joints are considered as resistance on connection,
which reduces length of connection pipe for 1 m (example: if there are 2 joints on flue connec-
tion, the connection cannot exceed length of 3 m). Flue connection must be fitted with joints
with inspections holes for cleaning (see figure 3). Joints must be out of at least 3 segments
(joints with three or more segments enable smooth flow of smoke gases through joint), it is
prohibited to use joints with two segments (joints with two segments creates resistance in flow
of smoke gases) (see figure 6).
• If the flue connection is longer as set forth in the instructions, the installer must use a reducing
element (from Ø 80 female connection to Ø 130 female connection) immediately behind the
fan, and the connection must be made with a pipe Ø 130 (see figure 21)
• Electrical connection of boiler must be performed with a cable (see figure 8) in accordance
with instructions. The boiler must not be connected to power supply with a plug – it must be
connected directly to network by a toggle switch, breaking live and neutral wire.
• Electrical connection of distribution elements (pumps, solenoid valves, electromotor valves...)
must be executed in accordance with the scheme in the instructions, i.e. supply for distribution
elements must be executed from connection cable on the boiler (cable "pump") (see figure 8).
• Combustion device Biodom 27 A, pipes of central heating and flue connection must be earthed
in accordance with professional regulations (earthing conductor with minimum cross-section
4mm
2
).