15
The flow rate in the circuit is between 0.5 and 1.5 litres/min for each collector.
The flow velocity in the circuit should not exceed 1.5m/sec otherwise the
the system may be noisy during operation.
As a guide only: systems with total pipework of less than 50 metres, 15mm
diameter pipe should allow flow conditions to be met for systems with up
to four collectors.
When the total pipework is over 50 metres, then 22mm pipe should be
used.
An assessment of the specific installation requirements must be
undertaken.
The installation of pipework must be made in accordance with good
plumbing practice, the following points should be considered when installing
pipework.
1.
Pipe runs should be chosen to give the shortest most direct route to
the storage cylinder, with minimum bends. Tight bends should be
avoided.
2.
The falls of pipes should be arranged to allow the system to be drained
and vented.
Low points, when unavoidable, should be fitted with a drain.
High points, when unavoidable, should be fitted with a vent.
3.
Where possible, all pipe runs should have a continuous slight incline
up to the highest point in the system to allow for natural venting of air
from the system.
4.
The automatic air vent supplied with the system should be fitted to
the highest point i.e. near the flow connection of the collectors.
5.
Adequate support and fixing should be provided for all pipework to
ensure that inclines are maintained and sagging is prevented.
6.
Owing to the high temperature differentials within the solar circuit
consideration should be given to the expansion of the pipework, expect
up to 12mm on a 5 metre run. Pipes should be fitted with brackets
and devices that allow for expansion and contraction, rigid fixings
should be avoided.
7.
A drain point must be fitted at the lowest point of the solar circuit. It
must be positioned at the down side of the non-return valve to ensure
the system can be fully drained.
All electrical connections must comply with current IEE Regulations.
The Pump is the only electrical connection for the Pump Group. This is
connected to the AST100 Controller’s R1 terminals via the cylinder manual
reset thermostat (thermal overload), refer to wiring diagram in the AST100
Solar Controller instructions.
1.
The pump must be connected using 1.0mm² 3 core heat resistant 3
core flex 3093Y marked at least to tolerate 85°.
2.
All cable sheath clamps must be correctly fitted.
3.
The conductor sheath must be continuous into joint enclosures.
4.
Conductors must be correctly fastened to terminals.
5.
Conductor insulation to be within 2mm of terminals
6.
All cable conductors external to joint enclosures must be insulated
and sheathed.
5.8 E
LECTRICAL
C
ONNECTIONS
5.6 S
IZING OF
P
IPES
5.7 P
IPEWORK
