Keystone KSTAW08INV-HC
window air conditioner · 8,000 BTU cooling · fits ~350 sq ft
Buy the Keystone KSTAW08INV-HC on Amazon — $569.99 →This exact model. Affiliate link.
A window AC rated 8,000 BTU — enough cooling for a room of up to about 350 square feet (ENERGY STAR's room AC sizing chart).
What actually decides this purchase
We publish 73 units at 8,000 BTU. They run within $15 a year of each other — but they sell for $260 to $570, a 2.2× spread. Efficiency is not what decides this purchase at 8,000 BTU; price, noise and whether it fits your window are. Here is where this unit lands.
At $570 this sits above the 8,000 BTU median of $354 — $215 more for cooling that costs the same to run, since the whole class is within $15 a year of itself. That premium has to buy something you can name: quieter running, a better warranty, a fit your window needs. Worth comparing against the TCL H8W4KW at $260 and the Friedrich CCV08A10A at 32 dBA for $519.
Price
$570
13th cheapest of the 14 units we have a price for at this size (median $354). Checked 2026-10-17.
Noise
Not published
The maker publishes no dBA figure we could verify, and noise is not part of the DOE certification. It is the most common complaint about window units, so treat its absence as a real unknown.
Window fit
≥ 19" wide
Derived from the certified cabinet width; confirm against the maker's sheet.
Circuit
Standard 115V
Plugs into a normal outlet — no electrician.
We do not have noise for this unit and will not estimate it. Everything above that carries a number is from a certification record or the manufacturer's own published sheet.
Buy this unit
$569.99 at Amazon
A window AC is a self-install unit: you set it in the window (or wall sleeve), no contractor or refrigerant charge needed. We matched this exact model’s Amazon listing — price shown was current at our last data refresh.
Sized for ~350 sq ft — measure your room and check your window type before you buy.
Check current price →Affiliate link. We may earn a commission — it never changes your price or our specs. Links to the exact listing; price can change at Amazon.
The Verified Label — every certified spec
certified 2023-04-07
status: Active
Cooling & efficiency — source: ENERGY STAR / DOE
Fit & install — does it fit your window?
Efficiency & running cost — computed by Verified HVAC Data
Worth keeping in proportion: every unit in the 8,000 BTU class runs within $15 a year of every other. The gap between the cheapest and dearest to buy at this size is 21× larger. Efficiency is the smallest number on this page, which is why it is not at the top of it.
Refrigerant & identity
Compare similar room ACs
Frequently asked questions
Is 8,000 BTU right for my room, or should I size up?
About 350 square feet is the guide figure, and 73 certified units sit on that shelf. The next shelf up is 9,000 BTU (6 units), about 400 sq ft. Below it, 6,000 BTU (17 units) covers about 250 sq ft. Between two shelves, take the smaller one: oversizing is the usual reason a unit cools but leaves the room clammy, which our sizing calculator explains.
Does the Keystone KSTAW08INV-HC heat as well as cool?
Yes — it is certified with a heating mode, so it works as a shoulder-season heater as well as an air conditioner. Only 30 of the 389 room ACs we publish do. It is supplemental heat for one room, not a replacement for a home heating system.
Does the Keystone KSTAW08INV-HC qualify for efficiency rebates?
It meets ENERGY STAR Most Efficient, the top tier some utility rebate programmes require. 28 of the 73 units in its 8,000 BTU class reach that tier, so it is one of several options at this size. Rebates are set by your state and utility, not by the manufacturer — check the programmes for your area.
Will the Keystone KSTAW08INV-HC fit my window?
Measure your window opening first — it needs to be at least 19" wide (the cabinet width), and the unit is about 14" tall and 22" deep, roughly 56 lb. Most double-hung windows fit units in this range with the included side panels, but confirm your window's inside width and minimum height.
Sources. Certification and CEER from ENERGY STAR room-AC data and the DOE compliance certification database. Cooling capacity, dimensions and refrigerant are the manufacturer-certified values. Annual running cost, suggested room size and the percentile are computed by Verified HVAC Data from published ratings and EIA U.S. average electricity prices — see our methodology. Refrigerant GWP is the IPCC value. We publish no star ratings and take no payment for placement. "Not published" means the source registry doesn't disclose it — we never fill a spec with a guess.