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Alpha CD13R, 18R, 24R
The Alpha CD Regular range of high efficiency condensing boilers are wall mounted, fan assisted room-sealed boilers.
The boiler CD13R is suitable for central heating loads of between 5.4 and 13.1 kW (18 400 and 44 700 Btu/h).
The boiler CD18R is suitable for central heating loads of between 5.4 and 19.6 kW (18 400 and 66 800 Btu/h).
The boiler CD24R is suitable for central heating loads of between 6.5 and 25.6 kW (22 200 and 87 300 Btu/h).
The boiler will provide central heating (as required) during the 'on' times set on your clock (if fitted).
Fig. 1
3
BOILER CONTROLS
2
USER CONTROLS
1
DESCRIPTION
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 heating 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 and frost thermostat will not operate when the switch is in the vertical position, i.e. 'Off' position (0).
3. INDICATOR NEONS
When neons A (red), B (red), C (yellow), D (green) are illuminated, the following conditions apply:-
Neon
D
Illuminated continuously - Electricity supply to the boiler is on.
C
Illuminated continuously - Burner is alight.
A
Flashing on and off - Temperature sensor fault, contact your Service Engineer.
B
Flashing on and off - Overheat thermostat has operated. Rotate selector switch to the reset position (3) to reset. If this continues
to happen, contact yor Service Engineer.
B
Illuminated continuously - Burner has failed to light. Rotate selector switch to the reset position (3) and the ignition
sequence will restart after a delay of about 30 seconds.
A and B Flashing on and off at the same time - Blocked flue or fan fault, contact your Service Engineer.
A Flashing and B Illuminated continuously - Pump fault or restricted flow.
A Illuminated continuously and B flashing - PCB or flame sensor fault.
A and B illuminated continuously - No flow or air present.
A, B and C flashing on and off at the same time - Contact your Service Engineer.
Note: Do not hold the selector switch in the reset position (3) for more than 2 to 3 seconds.
4. OVERHEAT THERMOSTAT
This thermostat automatically switches the boiler off in the unlikely event of the boiler overheating. When the thermostat operates,
the red neon (B) flashes on and off. Rotate the selector switch to the reset position (3) and the boiler will relight.
If this continually happens, contact your Service Engineer.
5. FROST THERMOSTAT
The boiler has a built-in frost thermostat, which automatically operates the boiler if the water temperature falls below 8°C,
providing the electrical supply is on and the selector switch is set to position (1) 'Frost' or position (2) 'ON'.
Central
Heating Thermostat
Frost
Thermostat position
Selector Switch
0
Indicator
Neons
1
2
3
1
2
3
4
5
6
7
8
9
RESET
ON
OFF
FROST
A
D
B
C
SELECTOR
THERMOSTAT
CD18R