Section 3: Primary Circuit Installation
Page 11
7.
The primary flow to heating zone 2 should be made to
cylinder connection E (refer to Figure 3-1 and Table 3-1).
•
Remove one of the 22mm straight compression couplers
from the accessories pack supplied with the cylinder and
make the connection to primary circuit connection E of
the cylinder (see Figure 3-1).
•
Primary circuit connection E of the cylinder can now be
connected to the 22mm flow pipe to heating zone 2.
8.
If required, the primary flow to heating zone 3 should be
made to cylinder connection D (refer to Figure 3-1 and Table
3-1). To do this:
•
Remove the top panel assembly (refer to Section 3.2.2)
•
Using a suitably sized spanner, remove the blanking
plug from connection D.
•
Use a 3/4” BSPM x 22mm compression coupler (not
supplied) and screw the 3/4” BSPM connection into
primary circuit connection D, ensuring a water-tight seal
is made.
•
Primary circuit connection D of the cylinder can now be
connected to the 22mm flow pipe and 2-port zone valve
(not supplied) to heating zone 3.
9. The return from the heating circuits should be connected to
cylinder connection A (refer to Figure 3-1 and Table 3-1).
•
Remove one of the 28mm straight compression couplers
from the accessories pack supplied with the cylinder and
make the connection to primary circuit connection A of
the cylinder (see Figure 3-1).
•
Primary circuit connection A of the cylinder can now be
connected to the 28mm return pipe to the heat pump.
3.2.2 REMOVING THE TOP PANEL ASSEMBLY
To remove the cylinder top panel assembly (refer to Figure 2-1):
1. Hinge open upper front panel to expose the expansion vessel
cover plate.
2. Remove the expansion vessel cover plate:
•
Carefully remove the five screws securing the expansion
vessel cover plate and remove the cover plate.
3. Remove the upper front panel and front top panel assembly:
•
Carefully remove the four screws securing the upper
front panel gas struts to the body of the cabinet.
•
The upper front panel and front top panel can now be
carefully removed as one unit. Gently lift the assembly
upwards and pull outwards, taking care not to bend the
locating tabs at the rear of the front top panel.
4. Remove the rear top panel:
•
Remove the two screws securing the rear top panel.
•
Gently lift the rear top panel upwards and pull outwards,
taking care not to bend the locating tabs at the rear of
the panel.
5.
Refitting is the reverse of removal.
3.3
HARD WATER AREAS
If the cylinder is to be used with a boiler, in a hard water area, we
recommend that the primary flow temperature be limited to 75°C.
This will help reduce the migration of suspended solids in the
water and help prevent the build up of lime scale.
3.4
THE 2-PORT VALVE
To prevent gravity circulation when the heat pump switches off,
three 2-port motorised valves have been supplied fitted to the
cylinder after the primary flow pipe from the ASHP. They are wired
in accordance with Figure 5-2 to ensure that, when used with a
Grant Aerona³ Heat Pump, the installation will comply with current
legislation.
For other makes of heat pump please check with the heat pump
manufacturer for connection details.
3.5
PRIMARY CIRCUIT EXPANSION VESSEL
An 18 litre expansion vessel with a pre-charge pressure of 1.0 bar
is supplied fitted to the primary circuit of the Grant QR integrated
indirect heat pump cylinders.
This expansion vessel is connected directly to the pipework
manifold underneath the rear top panel (see Figure 2-1).
This expansion vessel is located in a compartment above the hot
water cylinder. Refer to Figure 2-2.
No valve should be fitted between the expansion vessel and
cylinder.
The air charge pressure in this expansion vessel must be
regularly checked (e.g. at every service) and topped up as
necessary. This expansion vessel is supplied with a charge
pressure of 1.0 bar (equivalent to a maximum static head of 10.2
metres). The charge pressure must not be less than the actual
static head at the point of connection. Refer to Sections 7.1 and
7.4 for further details.
! NOTE !
Ensure that the expansion vessel used is of sufficient size
for the system volume.
Refer to BS 7074-1 or The Domestic Heating Design Guide
for sizing the required vessel.
3.6
AUTOMATIC SYSTEM BYPASS
A 22mm automatic system bypass is supplied factory fitted to the
Grant QR integrated indirect heat pump cylinder, for the purpose
of balancing the primary circuit. It is located behind the potable
hot water expansion vessel (refer to Figure 2-2 for position).
3.6.1 ACCESSING SYSTEM BYPASS
Refer to Figures 2-1 and 2-2. To access the automatic system
bypass:
1. Remove the upper front panel and front top panel assembly
by following the procedure outlined in steps 1-3 of Section
3.2.2.
2. Lift the potable hot water expansion vessel and carefully
place it on-top of the primary circuit expansion vessel.
3. The automatic system bypass can now be accessed for the
purpose of system balancing.
For information relating to balancing the primary system, please
refer to Section 6.8.
3.7
FILL & FLUSH VALVE
A primary circuit fill & flush valve is factory fitted to the flow pipe
to the indirect cylinder coil, below the DHW zone valve. Refer to
Figure 2-2 for location and Section 6.7 for information regarding
its use.
Содержание QR Range
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