Do I need a professional to install the Keystone 12,000 BTU Through-The Wall 230V Air Conditioner - Cool/Heat?

No. It is a window unit you can fit yourself, no professional needed. Usually no permit.

Window unit Heats too

Keystone

12,000 BTU Through-The Wall 230V Air Conditioner - Cool/Heat

Name: Keystone 12,000 BTU Through-The Wall 230V Air Conditioner - Cool/Heat
Brand: Keystone
Price: 649.99 USD
Availability: InStock

A window air conditioner rated at 12,000 BTU for rooms up to 550 sq ft. It heats in winter too and self-installs in a window.

$649.99

Live price at Sylvane

Price checked Sep 24, 2026

Buy at Sylvane

Performance

Cooling capacity: 12,000 BTU · 3.5 kW
Heating capacity: Yes
Room coverage: up to 550 sq ft
Energy Star: Not published
CEER: Not published
Annual energy (cooling): Not published

Noise, size & features

Indoor noise: Not published
Outdoor noise: Not published
Indoor unit: 24.2 x 14.5 x 20.3 in

Installation & the rules that apply

This is a window unit. No EPA Section 608 technician is needed: the refrigerant circuit is factory-sealed and never opened. A plug-in window unit needs no permit, so the friction is with your building rather than the government. Many HOAs restrict window units on appearance grounds, though an HOA regulating how you mount one stands on much firmer ground than one banning cooling outright. Landlords can set conditions, and the falling hazard is taken seriously: New York City, for instance, requires window units to be supported by brackets or mounting rails, and many building insurers and HOAs now require a bracket regardless of city.

Installation

Plug and play

Refrigerant

GeneralRenters: get written landlord consent firstReviewed June 2026Often blocks install

Common questions about the Keystone 12,000 BTU Through-The Wall 230V Air Conditioner - Cool/Heat

What size room does the Keystone 12,000 BTU Through-The Wall 230V Air Conditioner - Cool/Heat cool?: It is rated to cool a room up to 550 sq ft (12,000 BTU · 3.5 kW).
Do I need a professional to install the Keystone 12,000 BTU Through-The Wall 230V Air Conditioner - Cool/Heat?: No. It is a window unit you can fit yourself, no professional needed. Usually no permit.
Does the Keystone 12,000 BTU Through-The Wall 230V Air Conditioner - Cool/Heat heat as well as cool?: Yes. It also heats.

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