Need supplemental heat for upper floor

EdBoston

Hi all, we have an old Victorian house in the Boston area that was retrofitted for forced hot air/gas furnace sometime in the 80s. Our 3rd floor only has two ducts going up there so the heat is pretty marginal in the winter. I had been considering adding Mitsubishi Hyper Heat mini-splits. However the zone already has separate central AC via a coil and handler in the attic. One HVAC pro told me not to bother with mini-splits and just replace the AC system with a heat pump that uses the AC ducts coming down from the attic. He gave me a brochure for an Ecoer system that supposedly works down to -5 F. However it didn’t seem to me that he has much experience with the company, and I can barely find anything about it online including here. My questions are:

1) Should we just go with Mitsubishi mini-splits or try to use a heat pump with the existing ducts?

2) Does anyone have experience with Ecoer, or are there other cold climate products out there that we could look at for this purpose?

3) Should we just abandon the heat pump/mini-split ideas and try to run another forced hot air duct up to the attic? May be difficult but not impossible.

Thanks!

EBEBRATT-Ed

Here's a cheap solution which you may or may not want. If your heat is marginal and only needs a "boost" and your existing ac is ok you can probably install a small electric coil in your existing air handler, Wire this to be the "second stage" of heat and only use it as a booster

EdBoston

Good idea for using the existing AC hardware. Problem is that using the current heat for that zone is not really adequate for comfortable temps most of the time so I’m thinking of something that could be the primary heat source with forced air as the backup. What about using a heat pump with the existing AC handler/ducts? Seems less efficient than mini-splits but maybe still cheaper?