Fireplace dripping water

[crappiemiser]

I was at a friends cabin and when he lit the first fire of the year with his fireplace and water started to drip on the fire once it got rolling. He said it happens every year and it's only after the first fire does it drip. I think it may be due to heat loss from his forced air furnace being lost up the chimney. The fireplace does have a glass door that remains closed. Any other thoughts on this?

 

[Kevin in Ohio]

Temperature inversion. Cold steel/brick gets heat on it and it sweats if you will. Equipment in unheated barns will drip moisture when there are fast changes in air temperature, same thing. You can also see this with with Chimney covers in extreme cold situations. Hot air hits the colder steel and starts dripping and making a mess all over the roof and chimney.

 

[cantoo]

It's the tree huggers tears, they are crying over the loss of their brothers and sisters, the poor trees. Or it might just be condensation.
Please post your question on this site but don't link to Arborist site please. http://www.greenpeace.org/usa/

 

[barton174]

Normal. A biproduct of combustion is water vapor (just like in a car), not to mention the moisture cooking out of the wood. That moisture hits the cold chimney and condenses on the walls and drips back down.

Mike