Heatrae Sadia Multipoint ECO 100L V 3kW Installation, Operation And Maintenance Manual page 11

A suitable drain off valve should be installed in the
`
cold water supply to the appliance between the
Expansion Valve and the appliance at as low a
level as possible.
It is recommended that the outlet point of the drain
`
pipework be at least 1 metre below the level of the
base of the appliance (this can be achieved by
attaching a hose to the drain off valve spigot).
Hot water distribution pipework should be 22mm
`
pipe with short runs of 15mm pipe to terminal
fittings such as sinks and basins. Pipe sizes may
vary due to system design.
12
11
10
2
9
Figure 6: Typical installation - schematic (not to scale)
Item
1
2
3
4
5
6
7
8
9
10
11
12
Table 5: Typical installation table
PRV WARNING:
IF THERE IS AN UPSTREAM CHECK VALVE OR FITTING WHICH MAY PREVENT BACKFLOW
THEN HIGH PRESSURES CAN BE EXPERIENCED DUE TO AMBIENT TEMPERATURES
WHICH CAN CAUSE DAMAGE TO THE VALVES AND FITTINGS
8
6
7
8
9
9
NOTE:
If a device that prevents backflow is installed on
the cold water supply to the PRV then a means of
accommodating expansion due to local warming of the
pipe is recommended to be fitted between the Device
and PRV.
4
3
5 2
NOTE:
A backflow prevention Device may include,
check valves, a water meter or an
additional PRV
Description
Cold Water Mains in
Service Valve (not supplied)
Pressure Reducing Valve
Balanced Cold Water Draw Off
Check Valve
Expansion Vessel
Expansion (Pressure) Relief Valve
Tundish
To Drain (waste)
Hot out
Water heater
Temperature and Pressure Relief Valve
Back flow prevention
Device (if fitted)
1
2
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