Please refrain from answering stupid questions, it only encourages more of them to be asked.
To quote wowhead:
Hot Streak Rank 3
Any time you score 2 spell criticals in a row using Fireball, Fire Blast, Scorch, Living Bomb, or Frostfire Bolt, you have a 100% chance the next Pyroblast spell cast within 10 sec will be instant cast.
Thus, only those spells' crits (and, more specifically, only Living Bomb explosion, not tick, crits) will count for/against the Hot Streak counter. You need not worry about any other spells upsetting the counter, including Molten Armor.