furnace/refractory cement for venting a gas water heater to masonry

[guychampeau]

when venting the flue pipe from a gas water heater to a masonry chimney what is recommended to seal the connection between the chimney and vent pipe...furnace cement..refractory cement...or?...thanks

 

[breplum]

There are definite code maximums for appliances venting into masonry chimneys. The maximums must not be exceeded, due to the fact that warm air is trying to rise, and the mass of too large a masonry chimney will result in backdrafting of CO, which can be deadly.
Give the vent height, lateral distance of vent connector, diameter and material of vent connector and internal area in sq. inches of the chimney and I can tell you if your installation will meet code.
Any masonry mix will do to seal up, but

 

[voletl]

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