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[Abridged] The central field of the Andromeda galaxy (M 31) has beenmonitored, using the Chandra HRC-I detector (about 0.1-10 keV energy range)from 2006 to 2012 with the main aim to detect X-rays from optical novae. Wepresent a systematic analysis of all X-ray sources found in the 41 novamonitoring observations, along with 23 M 31 central field HRC-I observationsavailable from the Chandra data archive starting in December 1999. Based onthese observations, we studied the X-ray long-term variability of the sourcepopulation and especially of X-ray binaries in M 31. We created a catalogue ofsources, detected in the 64 available observations, which add up to a totalexposure of about 1 Ms. We present a point-source catalogue, containing 318X-ray sources with detailed long-term variability information, 28 of which arepublished for the first time. The spatial and temporal resolution of thecatalogue allows us to classify 115 X-ray binary candidates showing high X-rayvariability or even outbursts in addition to 14 globular cluster X-ray binarycandidates showing no significant variability. The analysis may suggest, thatoutburst sources are less frequent in globular clusters than in the field of M31. We detected 7 supernova remnants, one of which is a new candidate and inaddition resolved the first X-rays from a known radio supernova remnant.Besides 33 known optical nova/X-ray source correlations, we also discovered onepreviously unknown super-soft X-ray outburst and several new nova candidates.The catalogue contains a large sample of detailed long-term X-ray light curvesin the M 31 central field, which helps to understand the X-ray population ofour neighbouring spiral galaxy M 31.

X-ray source variability study of the M 31 central field using Chandra HRC-I