
Gradient
Gradient All-Weather 120V Window Heat Pump (9,000 BTU)
The Gradient is a different species from everything else here: a true cold-climate heat pump in a window-saddle body, delivering 9,300 BTU/hr of cooling and 9,000 BTU/hr of heating at full capacity down to 5°F (still functioning at -13°F), all from a regular 120V outlet. That means one machine replaces both your window AC and your radiator or space heater — the reason NYC's housing authority ordered thousands for apartment retrofits and why it made Forbes' innovative-technologies list. The variable-speed compressor runs 38 dB(A) on low, the design keeps your entire window view, and the 5-year warranty embarrasses the 1-year industry standard. So what's the catch? Price: about $3,800 per unit, roughly ten Midea Us. This only pencils out if you'd otherwise pay for electric resistance heat (it can cut those bills up to 50%), if a mini-split install is impossible or unpermitted, or if the 30% federal heat pump tax credit and state incentives apply to you. Early owner reports are positive on comfort and shocked by shoulder-season efficiency, with gripes limited to app maturity and the sheer bulk in smaller windows. Note that Gradient ended support for its Gen 1 'Moderate Weather' unit in August 2025 — the All-Weather 120V is the current product and the one to buy.
Specifications
Highlights
Pros
- ✓Replaces both AC and heater — true four-season comfort in one unit
- ✓Cold-climate rated: full capacity at 5°F, operational to -13°F
- ✓Plugs into an ordinary 120V/15A outlet — no electrician, no panel upgrade
- ✓Quiet 38 dB(A) low-speed operation with a variable-speed compressor
- ✓Full window view and daylight preserved by the saddle format
- ✓Eligible for the 30% federal heat pump tax credit and many state rebates
- ✓5-year warranty, by far the best in the category
Cons
- ✗$3,800 — approximately ten times the price of a Midea U
- ✗140 lbs across the sill; bulky in smaller windows
- ✗Needs 26 in minimum window width and a compatible sill depth
- ✗App and smart features still maturing per early adopters
- ✗No retailer review base yet — sold direct, so little crowd-sourced data
- ✗Heating output tapers in extreme cold, so far-north homes may want backup
Compare the Gradient All-Weather 120V Window Heat Pump (9,000 BTU)
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