I have an idea for a trap and I'm trying to get an idea of what the CR might be. I'm thinking at this point its actually two traps that are dependent on each other.
You have a 30x30 room with a door to the north and a small 20 foot hallway to the south. You travel down that hallway and you trigger the trap. The door shuts and locks. The room heats up to extreme temperature (1d6 fire damage per minute). A small fire elemental is summoned into the room every round for 10 rounds. This encounter/trap is dealt with when you either escape through the door somehow or disarm the trap (either option stops the heat and fire elementals and unsummons any already summoned elementals). If you wait it out, the trap deactivates after 10 minutes.
It seems like this trap is two pieces, the "elemental summoning" and the "heated room" piece. What is the CR for each piece? Or is there another way to build this trap mechanically?