Rocket Mass Off Season Smell

Listen, I love her but she smells a bit.
In the non heating season, we use a whole-house fan whenever it's not too hot to require air conditioning. Essentially the same as an attic fan but just mounted on a window on one end of the house to pull air through other open windows.
The side effect is that it pulls air through the mass heater chimney. It's not as bad as the clothes you wore around the smelly campfire but it's not pleasant either. Especially when it's moist outside. My wife does not appreciate this moist woody smokey smell (and I'm not overly fond of it either.)
I've experimented with putting plastic wrap over the firebox door to make that even more air tight. I have also been able to plug the bottom of the chimney with the access provided by the cleanout door. But I guess because of the bypass, there is still some airflow since that is not a 100% blockage.

Anyone else have this issue? What would you do with this annoyance? I could plug or even bag the top of the chimney and hope like hell I don't forget about that by the time the first fire of autumn is lit!  

A simple but effective remedy would be to reverse the direction of the fan. Positive pressure inside the house will blow air into the RMH and out the chimney.

The main drawback is that the small amount of waste heat generated by the fan is now added to air entering the house instead of being vented.

B Beeson wrote:A simple but effective remedy would be to reverse the direction of the fan. Positive pressure inside the house will blow air into the RMH and out the chimney.

Thanks but I don't believe that is really how these things work. The "suck fan" effectively makes every open window like a fan as breeze is pulled in, cooling those in front of them.
To reverse the fan and inject air in would only feel cooling if you were standing in front of it. The overall temperature would decrease over time but us inhabitants wouldn't feel it as much without the direct interaction of breeze.

Hiya Matt
I know that smell.  (sounds like a bad Jr high school game...)
Every so often, Shorty gets a dragony smell.
Not enough to bother us, but it does have a distinctive aroma when you notice it.
But it never sticks around very long either.
I do not notice the outdoor dragons having this smell, but both are in high-ceilinged, well-ventilated (leaky) spaces.
Also, both are first-gen designs; perhaps this is unique to the Shorty design?
An oddball idea might be to place a tin of baking soda through the cleanout door and see if that helps.

I was going to suggest the baking soda that Thomas suggested.

Another suggestion would be some orange peels or potpourri.

I wonder if it would help to open up the firebox doors and bypasses etc at night when the weather is hot so that air flows through and up the chimmey, cooling the house and carrying stale smells with it.