Download the user manual from Vokera. Login as trade go to literature should be there (maybe in old models). From memory.
The cold water main coming in goes to two taps, on restricts the maximum flow through the hot tap, so that when you fill a bath you dont get a fast fill of luke warm water, but rather a slow fill of hot water, the other goes from a tap through a flexible optionally removable plastic filling loop (often white) through a non return valve to the circulating water. It is this second tap you need to turn on to fill the system. Do not leave it permanently on, it should only take seconds to pressurise your system.
The mains water pressure may be above 3 bar, in which case (if you leave the filling tap open) the pressure relief valve will operate to protect the sytem and water will start coming out somewhere (hopefully outside). This is a bad thing, it may cause a permanent drip from the PRV, it will introduce fresh oxygenated water to your system and encourage corrosion, it is a waste of water etc etc. It also probably contrary to some bylaw.
cd
March 2007
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