Glenn FleishmanJan 24, 2023
I now have almost four years of electricity and natural gas use for my house via our utility companies. We put in a heat pump in May 2022. Previously, we had two window ACs in bedrooms that we ran almost entirely at night (and only some nights) and a bunch of fans. Last summer, with intense heat, you can barely see an increase in usage—particularly when you factor in inflation and a slow climb upwards in rates. (These are all two-month billing periods and average temps.)
Show threadGlenn FleishmanJan 24, 2023
This winter, with some bitter cold temps for Seattle last month, it looks like we paid about 5% less with the heat pump than the same period last year. But it's likely we used substantially more therms to heat the house. (Still compiling that data; it's hard to get apples-to-apples.) This chart shows hours used for AC, heat pump heat, and nat-gas heat. (We're still using the nat-gas furnace a bit; need to consider whether turning it off turns into a maintenance problem.)
Show threadGlenn FleishmanJan 24, 2023
Based on sheer hours during the coldest parts of December, it's possible we saved something like $75 to $100 in fuel over two months. Hard to pay off a heat pump with those savings, but the overall comfort and the switch to mostly electrical heating and cooling for environmental reasons and efficiency, *and the elimination of all the noise in the summer from fans!* absolutely worth it.
Show threadkcǃJan 24, 2023
@glennf how expensive was the heat pump and what kind of footprint does it take up? (I’m thinking of getting one for our small San Francisco home and am very curious)
Show threadGlenn FleishmanJan 24, 2023
@exkclamation We spent $10K for a modest house (1200 sq ft main floor; not using heat/cooling in day-lit basement) — 2-stage model. We didn't have any of the piping in place. So they had to "plumb" 40 feet of flexible piping and install the outdoor unit. They can be quite small! Ours is nearly a cube and the volume of maybe a standard refrigerator/freezer if you turned it into the cube.
Show threadkcǃJan 24, 2023

@glennf thanks! We're at 900sqft, so seems comparable!

Did you also get rid of previous heater? Or wait... (thinking) perhaps if you are in the PNW you just had baseboard heaters? We have a big box gravity-feed heater now (no blower, just heat floating up to the house), and wondering if it can take over the existing ducting.

Show threadGlenn Fleishman
@exkclamation We're not that moderate in temp! We have a nat gas furnace with integrated heat pump coil, so they just wired that up. We didn't remove the furnace as its integral to the install. We use it now as an automatic boost in the morning then it doesn't run the rest of the day
Jan 24, 2023 at 7:01pmWeb