Water Connections - General - andrews RFF 13/175 Installation And Service Manual

3.8

Water Connections - General

Fig. 4
Fig. 5
Hot water
service pipe
Union
adaptor
Gas cock
Gas control
Gas supply pipe
Check valve
secondary return via
tee in drain port
Issue 4 21042018
The upper "jet ports"
direct the flow outward
to begin the dynamic
mixing action.
The lower "jet ports"
direct the flow inward
to increase the
turbulence.
Open vent
Overflow
Cold water
cistern
Cold water
inlet valve
Flue
Thermostat
Drain cock
3.8.1 Hydrojet System
The heater is fitted with the Hydrojet Total Performance System
incorporated in the cold inlet dip tube. The tube is designed to
increase turbulence and reduce sediment build up, reduce
thermal stacking and increase delivery.
3.8.2 Water Connections - Vented Systems
The water heater must be supplied from a cold water feed
cistern and the hot water supply pipe must be fitted with an open
vent pipe in accordance with BS 5546. Local regulations and
bye-laws must be observed when installing the system but
typical water service layouts are shown in Figs. 5 and 7.
The cold water feed cistern must have an actual capacity
greater than the hourly recovery rate of the heater or heaters to
which it is fitted, the minimum actual capacity allowed for a feed
cistern is 227 litres.
Stop valve
The actual cistern capacity is the capacity to the normal water
line of the cistern. All cisterns used should be to the relevant
British Standard and the distance from the normal water line to
Cold water
the top of the cistern should be as laid down by the water
feed
authorities.
The cold water inlet and hot water outlet are identified on top of
the heater. Connect the cold water feed and hot water outlet to
these nipples with union adaptors for ease of servicing.
See
See Servicing Section 6.
Caution
Do not apply heat to these nipples if making capillary
soldered joints as they are fitted with plastic inserts. Make
the capillary joints to the pipes before connecting to the
heater. A drain cock is supplied with the heater and this
should be fitted to the appropriate boss as shown on the
drawing.
After installation of the water system open the main water supply
valve, flush the system and fill the heater. Open the hot taps to
allow air to escape from the system. When the system is free of
air, close the taps and check for leaks at the gas control
thermostat, drain cock and pipe connections at the top of the
heater.
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