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Zeus Mini Instructions
Filling the central heating system
The system design pressure (cold) should be set to 1.0 bar. This pressure is equivalent to a static head of
10.2 metres of water. Provision should be made to replace water lost from the system. This can be by
manual or automatic means.
Filling of the system must be carried out in a manner approved by the local authority. Where allowed, the
system may be filled via a temporary connection as shown below or by using the integrated filling valve in
the boiler. After filling, always disconnect the flexible hose of the filling loop if used and close the filling
valve in the boiler.
All fittings used in the system must be able to withstand pressures up to 3 bar. Drain taps (to BS 2879)
must be used to allow the system to be completely drained. The heating system should be thoroughly
flushed before the boiler is connected and again after the first heating. If it is necessary to add inhibitor to
the central heating system, contact RVR Ltd. for guidance.
The most important components of the system are shown in the diagram below.
•
The cold water supply for the water heating side of the system may come from a booster pump or the
cold water mains where this is permitted by the local authority.
•
A non-return valve must be installed on the cold feed to the boiler. This prevents expanding hot wa-
ter back-feeding into the cold side of the system.
•
An automatic bypass should be fitted in systems where central heating circulation can be shut off. (by
zone valves or thermostatic radiator valves).