My house (Portland, OR, 2900 sq ft) has central gas heating and central AC. The house was built in 2017 and is well insulated, but every winter we face an annoying problem: downstairs and upstairs temperatures are controlled by the same thermostat, so if we heat things up enough to make the downstairs comfortable, the upstairs is too hot. The downstairs area where this is most acute is ~700 sq ft.
The house came with a gas fireplace in the downstairs living room (which is open to the kitchen as well), but it stopped working this year, and I'd like to move towards less reliance on gas anyway. I'm considering two options for providing supplemental heat to the downstairs:
- An electric fireplace (taking the place of the current gas one)
- A heat pump (as an augmentation to the existing central heating & cooling systems, since the house is ~2900 sq ft, and I don't really want to install enough heat pump capacity to cover the whole thing right now)
I've been looking at an electric fireplace which is ~$1500 and can output either 4800 (at 120V) or 10000 (at 240V) BTU. I'd probably hire someone for installation and removal of the old gas unit, at unknown cost. A heat pump of similar or greater capacity seems like it would likely be more. As a reference point, when I had one installed in an previous house in 2016, the equipment cost was about $2700 (for a Daikin FTXS12LVJU, rated for 14400 BTU of heating capacity @ 47 degrees F) plus another $1700 for installation. (The installation of this unit might be easier, since it is on the ground floor instead of the 2nd floor.)
From this post, it sounds like the most efficient electric fireplaces have a COP (coefficient of performance) of just over 1.0, whereas the Daikin model I referenced above has a COP of >4.0 for heating.
From a cost and efficiency perspective, does it make sense to consider a heat pump for this purpose?