Here are some reminders for summer yoga:
Avoid doing asanas in direct sunlight, except at dawn or dusk.
Do not do dynamic sun salutations, especially 12 rounds. It may overheat the body. Switch to a more passive sequence that allows the body time to settle and rest in each asana for a comfortable amount of time.
Chair yoga is not strenuous and if your body is comfortable with it, it is fine to practice in a comfortable, cool room.
Avoid agnisar, bhastrika, kapalbhati, and surya bhedha. Instead practice sitali and seetkari, the two cooling breaths. Non-heating breaths are fine.