Worcester 15SBi User Instructions & Customer Care Manual

Central Heating

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 the appliance in this mode has been
factory set to mid-range or as reset by your installer. The appliance
Fig. 1. System Diagram.
Automatic air
vent
Boiler
Circulating
pump
Diverter valve
Domestic Domestic
CH
(optional)

hot water

cold
flow
out supply
4
will operate as necessary
to maintain the
temperature of the
radiators at the level set
Gas to water by the adjustment of the
heat exchanger
Heating Temperature
Control Knob. (See Fig. 2.)
If the system no
longer requires output to
maintain the desired
room temperature, the
burner will extinguish.
The pump will continue
to run for a short period
to dissipate the residual
heat from the appliance
and then switch off.
The appliance will
supply heat to the central
heating system as
required.
Hot Water
Expansion
A hot water cylinder will
vessel
be maintained full of hot
water under the control of
Pressure a cylinder thermostat.
relief valve
CH Relief Valve
return
discharge
MAINTAINING YOUR
APPLIANCE
Your new Worcester system boiler 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 08457 256206 for
help.
If you would like to know more about Worcester's extended
warranty options please tick the appropriate box on your
warranty registration card.
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