Removing a Wood Stove Flue Pipe

Topic: 
Heating and Cooling
Topic: 
Healthy Home and Environment
Question: 

We have decided to remove a wood stove from our living room and my husband has removed the pipe from the wall (chimney). When he originally installed the stove, he chipped a hole in the chimney and inserted a horizontal clay pipe. Now that the stove pipe has been removed, he has inserted a galvanized end cap on the end of the clay pipe. He says he is going to place a piece of wallboard over the opening in the wall.

My question is: Does the edge of the cap need to be sealed? If he doesn't seal it and then covers the hole in the wall with a piece of wallboard, will this be dangerous? I don't know who to ask about this and I don't totally trust my husband's judgement.

Answer: 

And now you want me to enter into this argument? It's bad enough that I regularly lambast "fly by night" contractors; now I could become a correspondent in a divorce! Well, OK I will try to be very even handed about this matter:

(1) Most appliances which require a chimney must be installed on a dedicated flue. As far as I know, there is only one exception - a gas furnace can be vented into the same flue as a gas hot water heater. All wood stoves, fireplaces etc. must be installed onto a dedicated flue. In other words, if the wood stove was installed into the same flue as any other appliance, removing it was a very good idea.

(2) If this flue is now being used by another appliance, then this would be a very good time to have it inspected, cleaned, repaired or lined by a chimney service. Any hole left over from the wood stove should be repaired with brick and mortar.

For example: if the flue is used for a gas furnace, a metal liner is highly recommend. Combustion of natural gas produces a lot of water vapor, this in turn can damage the mortar and brick in the flue. A damaged flue on a natural gas furnace can result in elevated CARBON MONOXIDE level in the home.

(3) If th