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3 Operation
Instructions for use VUI 362-7
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Fig. 3.4: Checking the water level
3.3 Domestic hot water operation
Warning!
The boiler should only be used when the heating
system contains water. Use of the boiler without
water may cause damage to the boiler or its
components.
Setting the maximum domestic hot water
temperature control
• Turn the main switch (2, Fig. 3.5) to the "l" position.
• The domestic hot water temperature can be adjusted
using the hot water temperature control (3, Fig. 3.5).
• Turn the control clockwise to increase the
temperature and anti-clockwise to decrease the
temperature.
As a guide for normal circumstances set the knob to the
one o´clock position.
Note!
This control adjusts the maximum domestic hot
water temperature. If adjusting the control
upwards appears to have no effect on the
temperature, then the boiler is already operating
at full output for the selected flow rate.
Warning!
If you live in a hard water area please do not set
the control knob above the mid (12 o'clock)
position to prevent excessive scale formation
(fig. 3.5).
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3.2 Initial checks before turning ON
3.2.1 Open the service valves
• Ensure the cold water service valve is open. This can
be checked by opening a hot water tap and ensuring
water flows.
• Ensure that the service valves in the heating flow and
return (2 and 1) and the gas service valve (3) are open.
Note!
The flow, return and gas service valves are open
when the line marking has the same direction as
the pipe.
• The pressure relief valves (4) are provided for safety
reasons and must not be interfered with.
Note!
A bottom cover is fitted to the appliance. The
service valves can be seen through the cover.
Fig. 3.3: Opening service valves
3.2.2 Check the water contents
• Check the water contents of the system on the
pressure gauge (1).
The needle on the pressure gauge (1) should be within
the green band (between 1 and 1.5 bar). If the needle
displays a value below 0.75 bar when the appliance is
cold, follow the instructions left by your installer to refill
the system. Alternatively, your installer should be called
to refill the system.
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