Detailed Discharge Pipe Installation Requirements (Combi Model); Collector System - Worcester 6 KW Instruction Manual

INSTALLATION
After the manifolds and the flow control valves, the coils are connected
to a collecting pipe. A filling link, filter and the plastic expansion vessel
supplied with the heat pump are connected to the collecting pipe. A
pressure relief valve is connected to the outgoing pipe.
One circuit at a time is filled with heat transfer fluid. Keep the valves
closed in the other loops during the process.
Fig. 17 Single circuit system
[1] Heat pump
[2] Expansion vessel
[3] Filling link
[4] Collector
Fig. 18 Multi-circuit system
[1] Heat pump
[2] Expansion vessel
[3] Filling link
[4] Manifolds
[5] Control valves
[6] Collector
13.2 DETAILED DISCHARGE PIPE INSTALLATION
REQUIREMENTS (COMBI MODEL)
The discharge pipework must be routed in accordance with part G3 of
schedule 1 of the building Regulations.
The tundish should be vertical, located in the same space as the
unvented hot water cylinder and be as close as possible and within
600mm of the safety device e.g. the temperature relief valve. The dis-
charge pipe from the tundish should be:
• made of metal
22
• at least one pipe size larger than the nominal outlet size of the safety
device (larger sizes may be required if the equivalent hydraulic
resistance exceeds that of a straight pipe 9m long - refer to BS6700)
• terminate in a safe place where there is no risk to persons in the
vicinity of the discharge, and position safely from electrical devices
• have a vertical section of pipe at least 300mm long below the tundish
before any elbows or bends in the pipework.
6 720 806 768-03.1I
Fig. 19 Typical discharge pipe arrangement
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
Valve
outlet
size
G1/2
<G3>/4 22 mm
6 720 806 768-04.1I
G1
Table 18

13.3 COLLECTOR SYSTEM

INSTALLATION AND FILLING
Installation and filling of the collector system should comply with
applicable laws and current regulations, the MCS MIS 3005 standard
should be referred to for guidance. Soil used for refilling around the
collector hose must not contain stones or other sharp objects. Pressure
test the collector system before refilling to ensure that the system is
watertight.
When cutting the collector, it is important that no dirt or gravel enters the
system. This can cause blockages in the heat pump and damage
components.
Safety device (e.g. temperature relief valve)
Metal discharge pipe (D1) from temperature relief valve to tunish
600mm maximum
Tundish
300mm minimum
Metal discharge pipe (D2) from tundish, with continous fall
Discharge below fixed grating
Fixed grating
Trapped gulley
Maximum
Size of Size of length of
discharge discharge straight pipe
pipework pipework (no bends or
D1 D2 elbows)
22 mm Up to 9 m
15 mm 28 mm Up to 18 m
35 mm Up to 27 m
28 mm Up to 9 m
35 mm Up to 18 m
42 mm Up to 27 m
35 mm Up to 9 m
28 mm 42 mm Up to 18 m
54 mm Up to 27 m
6 720 806 768-05.1I
Deduct the figure
below from the
maximum length for
each bend or elbow in
the discharge pipe
0.8 m
1.0 m
1.4 m
1.0 m
1.4 m
1.7 m
1.4 m
1.7 m
2.3 m
6 720 806 768 (2013/02)