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STEP 3 PIPEWORK CONNECTIONS
(General)
WARNINGS
Ensure pipework to and from pump is independently supported to
prevent forces being transferred to inlet and outlet branches of pump.
Do not introduce solder flux to pumps or pump parts manufactured
from plastic. All solder joints should be completed and flux residues
removed prior to pump connection.
Do not allow contact with oil or cellulose based paints, paint thinners
or strippers, acid based descalents or aggressive cleaning agents.
Always install isolating valves to both suction and delivery pipework.
Do not install a non-return valve, or devices
which contain non-return valves, in the
suction (inlet) pipework to the pump. The
pump must be free to vent to the supply
tanks at all times.
Hot Water Installations
If it is not possible to locate the pump in the preferred area due to site limitations and it
is necessary to position the unit in the loft, or in a position above the secondary tapping
that feeds the pump, then there is an increased risk of air locks. This risk must be
eliminated.
The following measure is a suggestion that may overcome the problem:
A "U" bend or downward loop in the supply pipe to the pump of 350 mm depth before
rising to the pump should ensure the cylinder vents its air up the expansion pipe, not up
the pump feed (Fig. 5).
Least Preferred Pump
Location (shaded area).
Pump located above the
hot cylinder can increase
the risk of air locks.
Fig. 5
Max. inlet head
10
m (
8
m for N1.3)
Min. inlet head
1
m
Max. outlet head
13
m (
8
m for N1.3)
Negative
head
Least preferred area
350
mm
min.
