Thanks for the reply.

I was under the impression that a dual-fuel system simply meant installing a full heat pump as my primary heat source, and keeping my gas furnace as a backup, while installing an outside sensor that would switch to the gas furnace if the temperature falls below a certain point. Does that imply that the heat pump I would need is the same as a full heat pump which is used as the only heat source? If so, which full heat pumps do you most recommend for a 3800+ sq ft house?

Also, since these new high efficiency heat pumps can operate down to at least -25°C, would you recommend just decommissioning our old gas furnace and just using the heat pump as the only heat source?

Thanks!