Worcester 26CDi Xtra User Instructions & Customer Care Manual

Hot Water Mode:
The appliance operates to supply only domestic hot water when the
heating temperature mode is fully anti-clockwise, at the off position or the timer
is programmed to OFF mode.
When a demand is made for hot water by opening a tap or shower, the flow
switch will energise the pump and circulate primary hot water around the boiler and
water to water heat exchanger. The burner will light at its maximum setting.
When hot water is no longer required the appliance pump and fan may
continue to operate to dissipate the residual heat within the boiler.
A flow restrictor is fitted within the appliance which limits a hot water
delivery rate to a maximum of 9.0 (±15%) litres/minute (2.0 gallons/minute).
Hot Water and Central Heating mode:
Fig. 1. Appliance Water Flow Diagram.
Automatic
Air Vent
Boiler
Circulating
Pump
Water To Water
Heat Exchanger
Water Diverter
Valve
CH
Flow
Domestic Hot Domestic Cold
CH
Water Supply
Water Out
Return
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When a demand is made for
heating by the system controls
(i.e. a programmer or room
thermostat). the pump will
energise circulating primary
water around the heating
system and the burner will
light. The heat output from
Secondary Heat
the appliance in this mode has
Exchanger
been factory set to maximum.
The appliance will operate as
Gas To Water
necessary to maintain the
Heat Exchanger
temperature of the radiators
at the level set by the
adjustment of the Heating
Temperature Control Knob.
(See Fig. 3.)
If the system no longer
requires output to maintain
the desired room temperature,
Expansion
the burner will extinguish.
Vessel
The pump will continue to
run for a short period to
dissipate the residual heat
from the appliance and then
switch off.
The pump will run for
the duration of the demand
Pressure Relief
and only shut off if the room
Valve
thermostat or programmer is
satisfied.
The appliance will supply
heat to the central heating
system as required. A demand
for hot water at a tap or
shower will override the
Condensate
central heating function for
Drain
the period of the domestic
hot water demand.
Safety
NOTE: If in doubt about
Relief
the use of the controls ask
your installer to assist you.
MAINTAINING YOUR
APPLIANCE
Your new Worcester 26CDi Xtra gas-fired appliance
represents a long-term investment in a reliable, high quality
product.
In order to realise its maximum working life, and to ensure
it continues to operate at peak efficiency and performance, it is
essential that your boiler receives regular, competent servicing
and annual maintenance checks beyond the initial 12 month
guarantee period.
Regular service contracts can be arranged with your installer
– however if you have difficulty making a satisfactory
arrangement simply contact Worcester on 01905 75624 for help.
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