8
Figure 5: Circuit layout for 20m
2
array (240 tubes)
2.4 Pipework and Expansion Vessel Sizing
Table 2 provides general guidance on the sizing of the system pipework and expansion
requirements. The expansion capacity is expressed as the number of Warmflow Solar
SEV18 expansion vessels required, each vessel having a volume of 18 litres.
No. of
vacuum tubes
Total length
of pipework
Minimum
pipe size
Minimum
expansion capacity
20
up to 70m
15mm
1 x SEV18
30
up to 45m
15mm
1 x SEV18
40
up to 30m
15mm
1 x SEV18
up to 40m
22mm
1 x SEV18
up to 75m
22mm
2 x SEV18
50
up to 10m
15mm
1 x SEV18
up to 45m
22mm
2 x SEV18
Table 2: Pipework and expansion vessel sizing
NOTE:
•
The total length of pipework is the sum of both the flow and return runs from the cylinder
to the collector and back e.g. if the cylinder and collector were 5 metres apart, the total
length of pipework would be 10 metres (if piped directly).
•
It is recommended that the minimum pipe size be used, otherwise expansion capacity
additional to that quoted may be required.
D
N
3
2
D
N
3
2
DN20
DN20
DN20
DN20
4 x SHP30 = 120 tubes
4 x SHP30 = 120 tubes
Note:
It is not recommended that more than
180 tubes be connected in series
