The star was discovered to be variable in 1927, with a photographic magnitude range of 15.3 to 16.5, at the Harvard College Observatory and designated HV 4013.

[12] AF And was often referred to as var 19, after its number in a Hubble list of variable stars in M31 and M33.

[5] AF And in outbursts has a peculiar emission line spectrum described as very much like Eta Carinae, likely due to a dense stellar wind.

The variability and lack of absorption lines defy a normal spectral classification, but it was suggested that it may be close to class A.

[16] AF And was the brightest star in M31 when it was first noticed during an outburst, at an apparent magnitude around 15, over a million times more luminous than the Sun.