Keystone KSTAW12INV-HC
window air conditioner · 12,000 BTU cooling · fits ~600 sq ft
A window AC rated 12,000 BTU — enough cooling for a room of roughly 600 square feet (the 20-BTU-per-square-foot rule).
What actually decides this purchase
We publish 91 units at 12,000 BTU. They run within $22 a year of each other — but they sell for $350 to $1,348, a 3.9× spread. Efficiency is not what decides this purchase at 12,000 BTU; price, noise and whether it fits your window are. Here is where this unit lands.
We have no tracked price for this unit, so here is the rule instead. At 12,000 BTU the field runs $350 to $1,348, median $490, and every one of them runs within $22 a year of every other — so price is the decision and efficiency is the tiebreak. On the certified specs we do hold, this one ranks 88th of 91 in its class. If the price you are quoted is above $490, buy something else. Worth comparing against the TCL H12W4KW at $350 and the Friedrich CCV12A10A at 32 dBA for $600.
Price
Not tracked
We have no verified retail listing for this certificate. Units at this size run $350–$1,348.
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 price or noise for this unit and will not estimate them. Everything above that carries a number is from a certification record or the manufacturer's own published sheet.
Buy this unit
Sold on Amazon — DIY install
A window AC is a self-install unit: you set it in the window (or wall sleeve), no contractor or refrigerant charge needed. We could not confirm a listing for this exact model number, so this opens an Amazon search for a Keystone window AC of this capacity — one we checked returns real results. Compare whatever you find against the certified specs above.
Sized for ~600 sq ft — measure your room and check your window type before you buy.
See matching units on Amazon →Affiliate link. We may earn a commission — it never changes your price or our specs. Opens a search, not a specific listing — we have not verified any individual result is this exact model.
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 12,000 BTU class runs within $22 a year of every other. The gap between the cheapest and dearest to buy at this size is 46× 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 12,000 BTU right for my room, or should I size up?
About 600 square feet is the guide figure, and 91 certified units sit on that shelf. The next shelf up is 13,000 BTU (5 units), about 650 sq ft. Below it, 11,000 BTU (4 units) covers about 550 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 KSTAW12INV-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.
Will the Keystone KSTAW12INV-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 58 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.