Does having a air conditioner in summer months increase the risk of sids?

I am not aware of any specific research that associates air conditioners & SUDI ( Sudden Unexpected Death in Infancy)

Red Nose does have the following information about room temperature.

It is not necessary to monitor the room temperature or to leave the heating or cooling on all night, as long as the baby is dressed appropriately for the room temperature.

To date, there is no evidence to show that maintaining a specific room temperature prevents SUDI and that thermal factors are implicated in SIDS as long as:
  The baby is placed to sleep on the back
  The baby is dressed appropriately for the room temperature (not over or under dressed)
  The baby’s head and face remain uncovered

https://rednose.org.au/article/room-temperature