Flue Damper

Steam Bunny

We've compromised and are planning to install an atmospheric Weil-Mclain LGB10 with a 16” draft hood outlet. Two of the Chimney's 3 stacks are available to accommodate two 12” flue pipes.

Would it be appropriate to install a motorized flue damper in each of these to help deter cooling the boiler and, in particular, help restrict warmed air from being drawn out of the basement during off cycles?

My primary concern is if they’re installed could they cause the mortar holding the chimney tiles in place to deteriorate, & if so what would cause this? Is it purely a matter of condensation, impurities from lack of maintenance? CO? And if deterioration is a possibility, is there a monitor we could install in the flue proper to alert us to a budding problem.

The chimney is minimally 45’ high consequently, when it cools down outside, there’s considerable draft even when the boiler’s off.

I’ve searched the Wall for information but without a copy of “The Lost Art of Flue Dampers”, my brain tends to cloud over as the experts nimbly switch from atmospheric to barometric, oil to gas, flue dampers to vent dampers, etc.

p.s. My first choice boiler would have been Ken’s (Palmer Heating) W/M 80 series but the noise from a 3450 rpm motor, was so amplified, as it ricocheted through the indirect ductwork, that portions of our first floor sounded like a converted factory. Hopefully, I didn’t make a dim-witted mistake by not viewing an HTD Power Flame in operation.

Thank you, Ken.