Grant EURFBH18MAX4, Installation, Commissioning & Maintenance Instructions

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turning the head counterclockwise until you hear a click. The click is
the head of the safety valve lifting its seat, allowing water to escape
from the system.
2. Check that water is escaping from the circuit.
3. Continue to fi ll the system until the pressure gauge indicates
between 0.5 and 1.0 bar.
4. Close the fi lling valve and check the balance of the installation,
correcting if necessary.
5. Water can be drained from the installation by manually operating
the safety valve until the desired pressure is reached. The pressure
of the cold installation must be between 0.5 bar and 1.0 bar. The
pressure is equivalent to the maximum static height in bars + 0.3 (1
bar = 10.2 meters of water), where the static height corresponds to
the vertical height between the center of the expansion tank and the
most top of the installation.
Now close the valves on each side of the fi lling loop and disconnect
the loop. Or close the backfl ow preventer.
7.1.5 HEATING SYSTEM
The maximum set temperature of the central heating water is 75 ° C.
See chapter 1.1.
An automatic air vent must be installed in the fl ow and return piping
lines from the highest point of the system.
If thermostatic valves are installed on all radiators, an automatic
type differential valve must be installed.
All fi ttings used in the system must be able to withstand pressures
of up to 3 bar. Thermostatic radiator valves must comply with the
requirements of standard NF EN215.
One or more drain valves must be used to allow the circuit to drain
completely. (one on low boiler and one on
low heating installation)
7.2 FILLING THE INSTALLATION WITH
CLOSED EXPANSION VESSEL
The air vent (s) are installed on top of the boiler (see Figure
7-2). Check that the small cap on top of each trap is screwed in
completely, then unscrew it one full turn - the cap now remains in
this position. The procedure for fi lling the installation with a closed
vessel is as follows:
1. Fill the heating circuit with water only when it is cold and the is
boiler off. Do not overfi ll.
2. Make sure that the supplied fi lling kit is connected and that the
double stop valve connecting it to the drinking water network is
closed. Attention, the installation of a standard backfl ow preventer
is recommended.
The valve is open when the control lever is parallel with the valve
body and closed when the latter is pendicular to the latter.
3. Open the fi ll valve.
4. Gradually open the double valve of the water supply network
until water fl ows out.
5. When the pressure gauge indicates a value between 0.5 and 1.0
bar, close the valve.
6. Bleed each radiator in turn, starting at the bottom of the
installation, to exhaust the air.
7. Continue to fi ll the installation until the pressure gauge indicates a
value between 0.5 and 1.0 bar. Close the fi lling valve.
8. Repeat steps 4 and 5 if necessary.
9. Close the fi lling valve on each side of the fi lling loop and
disconnect the loop. (or otherwise close the backfl ow preventer)
7.3 PURGE OF THE PUMP (ON HEATING
PUMP, OR PRIMARY PUMP OR DHW
PUMP)
However in many cases, it is important to mount a primary pump
(between Boiler and pressure case bottle)
It is important that the pump is properly vented to prevent it from
running dry, heating and damaging its bearings. The procedure is
as follows:
1. Remove the cap, then unscrew and remove the cap screw in the
center of the pump.
2. Using an appropriate screwdriver, rotate approximately one turn.
3. Replace the pump cap and cap.
7.4 SAFETY VALVE 3B
The operation of the safety valve must now be checked and
adjusted. The procedure is as follows:
1. Check the operation of the safety valve (see Figure 7-2) by
Heating circuits With sealed expansion vessel Page 25