Heating my bedroom - recovering chimney heat

In my last post I explored optimal ways to heat my bedroom using a small electric heater.  In this post I will detail how I have diverted trapped heat from around the chimney in the hallway to heat my room.  The chimney is cinder block and was exposed when my ex and I bought the house.  It was pretty ugly so I boxed it in with drywall on both floors, being careful to keep combustibles several inches from the hot surface.

The large wood stove in the basement is big enough to heat the whole house as heat rises from the open basement stairs and 2nd floor stairs to the bedrooms and bathroom.  The pictures below show the first floor boxed in chimney and the vents I installed to release the trapped heat.

   

By ventilating the closed space around the chimney I am releasing heat that could build up in the event of a chimney fire which is an added benefit.  But the primary goal was to recover this trapped heat.

My bedroom is adjacent to the chimney and I had used a similar scheme to ventilate the walled in chimney on the 2nd floor, but the vents both were in the hallway.  I decided to move the upper vent into my bedroom to divert the heat there.  This drawing shows the simple change I made:

Here's the bedroom wall before I cut the vent:

  

As you can see the area near the chimney is warmer than the other walls - through 2 layers of drywall!

After cutting the hole and closing off the vent in the hallway, I immediately felt warm air exiting the new vent in my bedroom.

 

With only a moderate fire going the heat coming from the vent is at least 10F hotter than the ambient room temperature. 

And after keeping the stove lit for a few days it's a lot warmer at the top vent (105F).

So I'm hoping this recovered heat will reduce the electricity needed to heat the bedroom.