Through-the-wall air conditioners sit flush with a wall opening, so protecting them from cold drafts, dust, and inclement weather is essential for efficiency. This guide highlights top covers designed to insulate, seal, and shield indoor and outdoor AC units of varying sizes. Each option is chosen for durability, ease of installation, and energy-saving potential. Below is a quick overview of the featured products to help you compare at a glance.
| Product | Brand | Size (L x H x D) | |
|---|---|---|---|
| COSFLY Indoor Air Conditioner Cover | COSFLY | 25 x 18 x 3.5 inches | Indoor use; fits units up to ~23-25″ x 16-18″ x 3″ |
| 2 Pack Indoor Outdoor Window AC Cover Set | BEWAVE | Indoor 25x17x3.5; Outdoor 25.5×20.5×18 | Two covers; indoor and outdoor use |
| FORSPARK Indoor AC Cover | FORSPARK | 28 x 20 x 3.5 inches | White indoor cover; simple drawstrings |
| DEMEDO Indoor Window AC Cover | DEMEDO | 17 x 13 x 3.5 inches (example size) | Multiple sizes; hook-and-loop seal |
| BOLTLINK Outside Window AC Cover | BOLTLINK | 25.5 x 21 x 17 inches | Heavy-duty outdoor protection |
COSFLY Indoor Air Conditioner Cover For Inside Units
Designed for indoor use, the COSFLY cover measures 25 x 18 x 3.5 inches, compatible with window units up to roughly 23-25″ x 16-18″ x 3″ (L x H x D). It emphasizes energy savings by blocking wind and cold drafts from entering through the unit. Installation is tool-free, with an elastic rim around the front and drawstrings on both sides to secure a snug fit. The 210D polyester/cotton blend balances durability with flexibility, helping to preserve heat in winter while protecting the unit from dust.
BEWAVE 2 Pack Indoor Outdoor Window AC Covers
This two-pack includes a dedicated indoor cover and a separate outdoor cover. The indoor cover uses 210D polyester and cotton, while the outdoor version is constructed from waterproof 210D oxford fabric to shield the unit from rain, snow, and debris. Both are machine washable and reusable. Easy installation requires no tools, with adjustable drawstrings on the indoor unit and two strap buckles on the outdoor unit to ensure a tight fit. A practical design includes two bottom-corner holes to accommodate power cables and maintain a tidy appearance during the off-season.
FORSPARK Indoor AC Cover
FORSPARK offers an indoor air conditioner cover designed to reduce heat loss and block cold drafts. The unit uses a durable 210D polyester/cotton fabric to shield the AC from dust while maintaining airflow control. It is lightweight and simple to install, featuring two adjustable drawstrings on each side plus a free extra cord for a secure fit. This model emphasizes energy savings by preventing cold air from entering through the window unit and extending the life of the equipment by limiting exposure to dust and moisture.
i frmmy Outside Insulated Window AC Cover
This heavy-duty outdoor cover is designed to guard exterior AC units against wind, rain, leaves, and UV exposure. It features a triple-layer construction: a waterproof outer shell, an aluminum foil mid-layer for heat reflection, and insulating pearl cotton inner layer. Adjustable straps with metal buckles secure the cover to prevent movement during storms. This model aims to improve energy efficiency by minimizing cold air drafts that can travel into the living space during winter months, while also protecting the unit from weather-related wear.
DEMEDO Indoor Window AC Cover
DEMEDO provides an indoor window AC cover with multiple size options to fit a range of units, typically around 17″ x 13″ x 3.5″. The product emphasizes a secure installation using hook-and-loop tape to seal gaps and prevent drafts. It also notes energy-saving benefits by blocking cold air from entering the room and helping to minimize heat loss. The brand focuses on a snug fit that resists sliding off, improving overall insulation during winter seasons.
BOLTLINK Outside Window AC Cover
BOLTLINK offers an outdoor cover designed to fit most standard window units up to 25.5″ W x 21″ D x 17″ H. Made from 600D waterproof oxford fabric, it includes two adjustable straps to keep the cover secure against wind and weather. The design prioritizes preventing cold drafts from entering the home by sealing the back of the unit, while also protecting the metal housing from moisture and corrosion. Suitable for outdoor installation, it complements a well-sealed exterior shutdown of a through-the-wall or window-mounted system.
Buying Guide
- Fit and sizing: Start by measuring your AC unit’s length, height, and depth. Choose a cover labeled to fit within your measurements, and consider a slightly larger option if your unit sits within a recessed sill or has brackets.
- Indoor vs. outdoor use: Indoor covers are designed to keep dust out and reduce drafts in living spaces, while outdoor covers provide weatherproofing against rain, snow, and UV exposure. For through-the-wall setups with exterior exposure, outdoor-grade materials are often preferable.
- Materials and construction: Look for water-resistant or waterproof fabrics, such as 210D polyester or oxford cloth, with an inner insulating layer for energy efficiency. A triple-layer design adds durability and better insulation.
- Sealing mechanism: Drawstrings, elastic hems, hook-and-loop closures, and adjustable straps help achieve a snug fit. Seals at the bottom corners or along the edges reduce air leakage.
- Ease of installation: Tool-free installation is ideal for seasonal changes. Verify that the cover can be secured quickly and remains in place during windy conditions.
- Maintenance: Machine-washable covers are convenient for periodic cleaning. Check care instructions to ensure long-lasting performance.
- Energy efficiency: A well-sealed cover reduces cold drafts entering the living space, supporting lower heating costs during winter without compromising comfort.
- Durability and warranty: Consider reinforced stitching and weatherproof fabrics. Some brands offer warranties or replacement options if fabric degrades or tears.
- Compatibility notes: If you have a through-the-wall unit with a protruding grille or external vents, ensure the cover design accommodates needed clearance and cable routing.