Unable to deactivate particle system

I am spawning a particle system component using spawn emitter attached node from inside my character blueprint.

I want emitter to deactivate and then destroy after a given duration of time, this duration can change depending on situation.

Emitters are set to loop forever and they have lifespan set to 1.
Kill on deactivate and completed checkboxes in required module of particle system are checked.

The rest of the set up is as shown in below image.

http://s12.postimg.org/73dmtonrh/Untitled.png

But unfortunately particles are neither deactivating nor destroying.

Any help is appriciated .Thanks in advance.