two red lights on alpha combi cd 24/32c no hot water or heating?

As per makers insructions
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.
B Flashing on and off - Overheat thermostat has operated. Rotate selector switch to the reset position (3) to reset.
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.
A and B Flashing on and off alternatively - System pressure is very low and re-pressurisation is required

ivor
October 2008