I have a living room that was an addition. There is only one 6" duct running into the front of the room. The room is 12x20. The duct os on the 12' side under the step down into the room. At the other end is a wood stove that i plan to replace to a gas stove someday. The room is not receiving enough heat. Would a booster fan help? What else could i do? I forgot to mention the room is on a slab.

So is the heat coming out of the outlet where the step down is at the entrance to the living room.. and then just immediately leaving the livingroom for the closest return air in your home?

Is the gas stove going to be thermostat controlled?

Find a way to run another 6" supply to that room.

It comes right out under the step, there is no return in the room. The only way i could run another pipe is next to the one that is already there. I need air to the other end of the room.

Ain't goona get air to the other end from one 6" supply.

is it possible to remove the 6" and replace it with 8" you would get more cfm which may help....ben sr

I dont think there is enough room. Theres wires running through the joist.