Wood Stove/Tankless Water Heater Flue

[KenandDeb]

Do you guys see a problem with attaching the vent pipe from an Eccotemp tankless water heater to the wood stove flue?

[rossvtaylor]

Besides the uncertainty of proper flow, which could lead to CO poisoning, the exhaust of your tankless heater will contain a fair bit of water vapor (moisture) as a product of the combustion. All vented tankless water heaters I've seen or installed require that the vent pipe have a downward slope at the exit, so that moisture condensation will flow out of the structure. If you try to vent into the wood stove flue, that moisture will most likely run down into the stove.

[KenandDeb]

Originally Posted by rossvtaylor

Besides the uncertainty of proper flow, which could lead to CO poisoning, the exhaust of your tankless heater will contain a fair bit of water vapor (moisture) as a product of the combustion. All vented tankless water heaters I've seen or installed require that the vent pipe have a downward slope at the exit, so that moisture condensation will flow out of the structure. If you try to vent into the wood stove flue, that moisture will most likely run down into the stove.

Makes sense. Thanks

[Rucker]

Agreed.

And, I think these instant heaters have a positive fan for the exhaust. I could be wrong on some models but mine does and it wouldn't play well at all with a naturally convected flue.

Separate vent would be best.