INSTALLATION INSTRUCTIONS
24
4.2 Filling the system
Check the properties of the water supply and
install the appropriate treatment devices if the
mains water has a hardness rating more than 25 °f,
i
n
order to prevent scaling and eventual damage to
the D.H.W heat exchanger.
Use only clean tap water to fill the system.
If antifreeze chemical agents are used to fill the
system, install a hydraulic compensator on the
filling system in order to separate the heating
circuit from the D.H.W circuit.
Before switching the power supply ON, fill the system
as follows:
•
Check that the circulating pump runs freely;
•
Check that the plug of the air vent valve has been
slackened slightly to allow air to escape from the system
(fig. 1);
•
Connect a rubber pipe to the draining tap placed on
top of the condensing heat exchanger (fig. 3) and
turn it counter-clockwise.
•
open the filling tap
R
(fig. 2);
•
to direct any air away from the system;
•
close the draining tap placed on top of the condensing
heat exchanger (fig. 3);
•
use a pressure gauge
M
(fig. 2) to check that the
system pressure reaches the middle part of the green
zone corresponding to 1.2 bar (fig. 4).
•
On completion, make sure that the filling tap R is
perfectly closed R (fig. 2).
•
Unscrew the plug on the pump to remove any trapped
air, check that the pump is free then re-tighten it when
water starts to flow out (fig.1);
•
Open the air vents on the radiators and monitor the air
evacuation process. When water starts to flow out of the
radiators, close the air vents.
If, after the above operations, there is a pressure reduction,
re-open the filling tap
R
until the pressure gauge reaches
the middle part of the green zone corresponding to 1.2 bar
(fig. 4).
4
3
2
1
GREEN ZONE
1.2 bar
0.5 bar
1.5 bar
3 bar
PUMP PLUG
PUMP
AIR VENT VALVE PLUG
AIR VENT VALVE
M
R
Summary of Contents for RK 25 /B
Page 2: ......
