Replacement of parts
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8
Replacement of parts
8.1
Draining the appliance
District and central heating system
Many of the tasks in this section require that the appliance be isolated
and drained. This will be indicated in the manual if required.
▶ Isolate the appliance from the district and central heating system
using the appliance isolation valves.
▶ Connect a suitable hose firmly to the require drain point and run the
hose outside to a suitable point or container.
▶ Turn the drain valve anti-clockwise to open the drain. Turn the valve
firmly clockwise to close.
Fig. 62 Drain point connection
Domestic water system
▶ Isolate the cold mains inlet isolation valve.
▶ Drain the domestic water system.
8.2
Plate heat exchanger
Refer to figure 63
▶ Ensure the appliance is fully drained.
▶ Undo the screws on the securing brackets [2].
▶ Remove the securing brackets [2] and plate heat exchanger [1].
– Ensure that the seals [3] are removed from the upper [5] and
lower [4] connection plates before replacing with new ones.
▶ To refit follow the above actions in reverse. Ensure any seals that
have been disturbed are renewed.
– When replacing ensure the correct plate heat exchanger is fitted.
– Ensure the bracket securing screws are evenly tightened when
refitting.
Fig. 63 Plate heat exchanger removal
CAUTION:
Accessing internal components:
▶ Isolate the district heating and the electrical mains
supply before starting any work on the appliance and
observe all relevant safety precautions.
NOTICE:
Risk of water damage to appliance or property!
Damage from disconnecting water pathways which may
have retained some water.
▶ Take care after draining appliance to protect
equipment/property from residual water content
within components.
6720808926-35.1W
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1
3
2
Correct orientation
▶ When refitting the plate heat exchanger ensure it is
correctly orientated, the label will have an arrow
below the heat exchanger usage
or
. Also
ensure the correct one is fitted, the label will match
the symbol on the insulation behind the heat
exchanger being replaced.
NOTICE:
Damage to bracket and possible leaks
If one side is torqued down before the other, the
brackets could be damaged and prevent correct sealing
of hydraulic joints.
▶ Ensure the bracket securing screws are evenly
tightened which will refit the heat exchanger square
and level, creating a good hydraulic seal.
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4
5
1
3
Summary of Contents for Worcester Greenstar HIU
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