Thermsaver unvented water heater, Installation Manual

Page: 5 / 12

5
CONNECTING THE WATER SUPPLY
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Pipework is not supplied
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All pipework should be installed using good plumbing practice.
We recommend 22mm mains cold water supply is used.
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Install a Stop Cock Valve before the cold water inlet assembly on
the incoming mains water supply so the unit can be isolated if
required.
COLD WATER VALVE
The combined cold water valve (supplied) can be connected
anywhere on the cold water mains prior to the unit. It can even be
located at a point near to where the mains supply enters the
premises if this is more convenient. When installing the cold water
valve, ensure that the arrow is pointing in the same direction as the
mains water supply flow when connecting, see fig 2.
The cold water balancing port, on the valve, allows you to connect
the cold water mains to the rest of the property thus giving
balanced pressure throughout. If this facility is not required leave
the cap on.
DRAIN TAP
A drain tap to drain the unit must be fitted to the cold-water inlet
pipe somewhere between the unit and the cold water
valve assembly and at as low a level as possible, see fig. 1.
PIPEWORK TO TAPS
Ideally a 22mm pipe run should supply the outlets throughout the
property with short lengths (max 1 metre) runs of 15mm going to
baths, showers, and basin taps. Smaller bore pipe can be used to
suit taps.
SECONDARY CIRCULATION
This is particularly easy to fit on unvented units; a Swept Tee
(not supplied) is needed for all indirect models if secondary
circulation is required, see page 6 fig. 3 for fitting. A non-return
valve (not supplied) must be fitted to prevent backflow. You will
need a pump to circulate the hot water (not supplied). The return
feed is in 15mm pipe and all work can be done on site.
Fig.1
Fig.2
Typical Indirect Tank installation using external expansion vessel
Cold water inletvalve assembly
PRESSURE REDUCING VALVE
SET AT 3 BAR
WATER FLOW INLET SIDE OF TANK
WATER FLOW FROM EXPANSION
TANK TO 22MM FEMALE THREAD
BEHIND COVER
BLANKED
PORT
WATER FLOW
HOT WATER OUTLET
PRIMARY FLOW
PRIMARY RETURN
TWIN
THERMOSTAT
IMMERSION
HEATER
WATER FLOW
TO COIL INLET
WATER FLOW
FROM COIL INLET
7 BAR / 90 DEGREES
PRESSURE &
TEMPERATURE
RELIEF VALVE.
TUNDISH
WATER FLOW
TO OVERFLOW
WATER INLET
DRAIN
COCK
SECONDARY
RETURN FLOW
SWEPT TEE
EXPANSION VESSEL
(WALL MOUNTED)
WATER FLOW TO
MANFOLD VIA
FLEXIBLE HOSE
6 BAR
EXPANSION
RELIEF
VALVE
PRESSURE
REDUCING VALVE
SET AT 3 BAR
WATER FLOW
INLET SIDE OF TANK
BLANKED
PORT
WATER FLOW
FROM EXPANSION
TANK TO 22MM
FEMALE THREAD
BEHIND COVER
6 BAR
EXPANSION
RELIEF
VALVE
BALANCED
COLD WATER
OUTLET