13
2)
Accommodation of expansion in an expansion vessel
(diagrams 4 & 5).
diagram 4
MW 10/15
diagram 5
EW 10/15
Using a pressure reducing valve (set at 3.5 bar), a non-return valve and
expansion vessel charged to 3.5 bar, the expansion is accommodated in the
vessel. This operates on the hydraulic principle; i.e. the expanded water is forced
into the expansion vessel due to the in-line non-return valve. The vessel pressure
charge is increased as it accommodates the expanded water, so that the water is
discharged from the vessel when the hot draw off is opened.
Please note that in ALL cases the DIELECTRIC JUNCTIONS MUST be
connected to the heater before any other connection is made. This is very
important as they prevent an electrolytic reaction occurring and safeguard
the heater against potential aggressive corrosion.
Only the use of copper pipe is recommended for connection to the heater. If
any other material is used it must be able to withstand 90°C at 7 bar
pressure for long periods.