Why isn't my wood stove sucking smoke up into the chimney?

When mine does this I light paper and stick it up to the chimney, holding it there with my hand. As the heat rises it starts the flow going up. Then light more paper and keep it going. Good Luck.

I don't know what's making the smoke back up but if smoke is pouring out through cracks in the chimney then your chimney is in terrible shape and I wouldn't light a fire in that stove until the chimney has been fixed. House fire waiting to happen. If smoke can get out, so can hot air when the stove is in operation. That hot air can set fire to the house. Happened to some people I knew, in the middle of the night a couple of hours after they had gone to bed with the fire in the fireplace still burning but burning low. They were lucky to get out alive. There was a small gap in the brickwork of their 10 year old chimney, where someone had done shoddy work and tried to fill a small gap with mortar instead of a piece of brick. A flue is not what you use to let more air in at the bottom of the stove. That's a damper. A flue and a chimney are basically the same thing. They allow smoke to escape where you want it to escape from. Did you clean the chimney from the top? Is there a spark arrestor that has become clogged? Are there unusual wind conditions today?

You lost your updraft. Extending the chimney should solve the problem, but if you need heat in the mean time, blow the discharge from a vacuum cleaner up the chimney and this should get it working again.

Call a chimney sweep and have it cleaned out if you son't you could have a serious fire. You also may have bird nests in the chimney that will clogg it. But do not try and use it until it gets cleaned out you could burn your place down.

Sounds like it is windy . If so you are getting a back draft. Best solution is extending chimney pipe 2 or 3 ft higher.

It could be blocked or need cleaning, when was that done last?

It should be obvious whether the flue is open or closed, choose open.

Otherwise, you may have a down-draft, or the house is too well sealed.

Try opening a window or outside door slightly, just to test.

Once the flow is established & hot air is rising, it should keep going.

wind will do this. you need a chimney cover.