Grant QR Range, Инструкция по установке, обслуживанию и эксплуатации

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Section 4: Secondary Circuit Installation Page 12
4.1 GENERAL
Grant QR integrated indirect heat pump cylinders are supplied
with all the necessary safety devices and components required for
an unvented hot water system. For a list of these safety devices
and components refer to Table 2-2 in these Installation and User
instructions.
These cylinders are supplied with these safety devices and
components factory fitted, requiring only the following to be
carried out by the installer:
•
Connect the cold water supply pipe to the relevant
connection point. Refer to Sections 4.2 and 4.3 for details.
• Connect the discharge pipe to the outlet of the Tundish.
Refer to Section 4.9 for details.
For commissioning and maintenance purposes, it is essential to fit
a service valve (not supplied) in the cold water supply pipe, before
the inlet manifold.
The ½ʺ drain cock is factory fitted (refer to Figure 2-2 for location)
to provide a means of draining the unit.
4.2 COLD WATER INLET MANIFOLD
This manifold contains a pressure reducing valve, double check
valve and expansion relief valve with a stainless steel seat.
The pressure reducing valve is factory set to 3 bar. The set
pressure is shown on top of the valve. The maximum inlet
pressure to this valve is 12 bar.
A balanced cold water connection is provided on the inlet
manifold. Refer to Figure 4-1. This should only be used to provide
balanced cold supplies to shower valves and mixer taps. If the
balanced cold water outlet is not required, blank off cylinder
connection H (see Figure 3-1).
4.3 INSTALLATION
1. Cold water supply pipe to be 22mm nominal size.
2. Flush supply pipework before connection to remove all flux
and debris prior to connecting the water supply.
Failure to do this may result in irreparable damage to the
controls and will invalidate the warranty.
3. Once the pipework is flushed connect the cold supply to
cylinder connection I (refer to Figure 3-1). To make this
connection, remove one of the 22mm straight compression
couplers from the accessories pack supplied with the cylinder
and make the connection to cylinder connection I (see Figure
3-1). A service valve (not supplied) must be fitted in the cold
supply to the cylinder before this connection is made.
4. The expansion relief valve should be either horizontal or
upright - if fitted inverted, debris may be deposited on the
seat and cause fouling of the seat when the valve operates.
Check direction of flow arrows.
5. If the installation requires one, a pressure gauge should be
sourced and fitted on the cold water supply to the cylinder,
between the inlet manifold and the cold water inlet tapping on
the cylinder.
6. A potable hot water expansion vessel is supplied fitted to
the secondary circuit of the cylinder. Refer to Section 4.4 for
more information on the expansion vessel.
7. The expansion relief drain and the T&P relief valve are both
connected to the tundish (see Figure 2-2). This pipework
must be connected to a safe visible discharge point via
the tundish (supplied fitted) and the pipework must have
a continuous fall. Refer to Sections 4.9 to 4.13 for further
information on the Tundish and Discharge pipe.
8. The pressure reducing valve has two outlets, the first being
the cold supply to the cylinder; the second one is for a
balanced cold water supply, to a shower or a bidet (over rim
type only, ascending spray type requires type AA, AB or AD
air gap).
Major shower manufacturers advise fitting a mini expansion
vessel in the balanced cold supply to accommodate thermal
expansion and prevent tightening of shower controls.
If the dwelling has a shower mixing valve (manual or
thermostatic) or a Bidet (over rim type) use the cold water
supply from the balanced cold water connection on the inlet
manifold for these outlets.
If a balanced cold water supply is required, connections
should be made to cylinder connection H (refer to Figure
3-1). To make this connection, remove one of the 22mm
straight compression couplers from the accessories pack
supplied with the cylinder and make the connection to
cylinder connection H (see Figure 3-1).
Do not use the balanced cold connection to supply bath taps
as this can reduce the flow of water available to the cylinder.
If the balanced cold water outlet is not required, blank off the
connection.
9. The Service Log at the back of these instructions should be
completed after commissioning of the system.
4 SECONDARY CIRCUIT INSTALLATION
Figure 4-1: Cold water inlet manifold
Expansion
relief valve
Pressure
reducing valve
Circlip
Balanced cold
outlet
¾” BSPF expansion vessel
connection.
(Remove black plug prior to
connection)
Expansion
relief
Cold inlet
to cylinder
Cold water
supply