33
Instruction for the installer
3.15 – FILLING THE SYSTEM
Warning!
Do not mix the CH system’s water with
unsuitable anti-freeze products (example:
anti-freeze solutions for motor vehicles) or
use wrong concentrations of anti-corrosion
solutions ! This could cause damage to the
washers and could provoke noise during
normal boiler operation.
If really necessary, use exclusively specific
anti-freeze products suitable for use on
aluminium-silicon alloy.
UNICAL refuses all liability for injury to
persons, animals or damage to property
deriving from not having respected the above
mentioned recommendations.
After completing all the system’s service connections the
circuits may be filled by carefully following out the following
phases:
-
open the radiator’s air vents and check that the automatic
air vent in the boiler is working properly.
-
gradually open the appropriate filling cock and check that
the automatic air vents fitted onto the system are working
properly.
NOTE:
The minimum low water pressure switch will
not give the electrical impulse to fire the
burner if the pressure is lower then 0,4 bar.
The pressure of the water in the CH system
must not be lower then 0,8/1 bar; if this value
is lower use the filling cock on the boiler to
adjust the pressure.
This operation must be carried out when the
system is cold. Use the pressure gauge fitted
on the boiler to read the circuit’s pressure
value.
NOTE!
If the boiler has not been fired for a long period
the pump could be jammed. Before firing the
boiler, it is important to carry out the following
un-jamming operation:
-
place a cloth underneath the pump
-
remove the pump vent plug positioned in
the centre of the pump
-
using a screwdriver, rotate the shaft in a
clockwise direction.
Once this operation has been concluded,
screw back the pump vent plug and check that
there have been no water leaks.
WARNING!
After removing the pump vent plug some
slight water leakage could occur. Before
replacing the front panel dry all the wet
surfaces.
-
close the radiator’s air vents as soon as water begins to
flow out.
-
using the pressure gauge check that the pressure reaches
the value of 0,8/1 bar.
-
close the filling cock and then bleed off the air once again
through the radiator’s air vents.
-
check all the connections for soundness.
open
close
FILLING COCK
ALKON 35 S C
open
close
FILLING COCK
ALKON 35 S R
-
after having fired the boiler and the system has reached
the correct temperature , stop the pump and repeat the air
bleeding operations.
-
let the system cool down and, if necessary, re-establish
the water pressure to 0,8/1 bar.
