Description; User Controls; Boiler Controls - Alpha CD18S User Instructions

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DESCRIPTION

The Alpha CD18S, 24S and 30S are high efficiency condensing wall mounted, fan assisted room-sealed system boilers.
The boilers are system boilers providing heating only for sealed central heating systems.
The CD18S boiler is suitable for central heating loads of between 4.7 and 19.5 kW (16 050 and 66 500 Btu/h).
The CD24S boiler is suitable for central heating loads of between 4.7 and 25.4 kW (16 050 and 86 700 Btu/h).
The CD30S boiler is suitable for central heating loads of between 6.5 and 29.8 kW (22 200 and 101 700 Btu/h).
The boilers will provide central heating (as required) during the 'on' times set on your clock (if fitted).
The burner is lit electronically.
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USER CONTROLS

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BOILER CONTROLS

1. CENTRAL HEATING THERMOSTAT
This thermostat controls the temperature of the water leaving the boiler for the heating system. For maximum efficiency from the
boiler the thermostat should be left at number 5 or 6 as shown in Fig. 1. If lower heating temperatures are required, turn the thermostat
anti-clockwise. If higher temperatures are required, turn the thermostat clockwise.
2. SELECTOR SWITCH
This control is used to turn the boiler on and off or to 'reset' the ignition sequence or to set to frost thermostat only. The internal
clock (if fitted) and frost thermostat will not operate when the switch is in the vertical position, i.e. 'Off' position (0).
3. PRESSURE GAUGE
This indicates the central heating system pressure. It should always be within the green band when cold, increasing slightly
when hot.
If the pressure falls below the green band, i.e. lower red area, the system needs re-pressurising. Contact your Installer to have
the system checked and pressurised.
Alpha CD18S/24S/30S
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Fig. 1