Whirlpool WHAT122-HAW Review: 12,000 BTU Wall AC with Heat, 230V
Whirlpool's 12,000/11,600 BTU wall unit adds 10600/8600 BTU of supplemental heat for spaces up to 550 sq ft, runs on 230V/15A and fits sleeves 24.5 to 27 inches wide.
By Daniel Brooks
Updated October 22, 2026
The Whirlpool WHAT122-HAW is a 12,000 BTU through-the-wall air conditioner with supplemental heat, rated for spaces up to 550 square feet. It delivers 12,000/11,600 BTU of cooling and 10600/8600 BTU of heat depending on supply voltage, plugs into a 230V/15A outlet, and fits sleeves from 24.5 to 27 inches wide. It has a 4.0 out of 5 average from 10 ratings in our through-the-wall air conditioners with heat category.
Our Verdict
The WHAT122-HAW is an easy recommendation for a living room, large bedroom or studio apartment that needs a replacement wall unit with heat. Its universal fit chassis takes a wide range of sleeve sizes, the heater is strong, and the controls are simple: 3 fan speeds, 4 operation modes, 8-way louvers, Eco and Sleep functions and a 24 hour timer. It also removes up to 1.6 pints of moisture per hour.
There is no Wi-Fi, and Whirlpool is clear that the heater is supplemental. It is designed to take the chill out of early fall nights, not to be a primary heat source in the coldest months. You will also need a 230V/15A receptacle at the sleeve.
Whirlpool 12,000 BTU Wall Air Conditioner
As an Amazon Associate we earn from qualifying purchases. Product prices and availability are accurate as of the date/time indicated.
Key Specifications
| Feature | Specification |
|---|---|
| Brand | Whirlpool |
| Model | WHAT122-HAW |
| Type | Through-the-wall air conditioner with supplemental heat |
| Cooling Capacity | 12,000/11,600 BTU |
| Heating Capacity | 10600/8600 BTU |
| Room Size | Up to 550 sq ft |
| Power | 230V/15A outlet, 4.9 ft cord |
| Efficiency | 9.6 (listed) |
| Dehumidification | Up to 1.6 pints per hour |
| Noise Level | 57 dB (listed) |
| Controls | On-board electronic controls and remote |
| Dimensions | 24.2 x 14.5 x 20.3 inches (W x H x D) |
| Sleeve Fit | 24.5 to 27 inches wide |
| Weight | 72.3 pounds |
Cooling Capacity and Room Size
Whirlpool rates the WHAT122-HAW for spaces up to 550 square feet. The ENERGY STAR chart below places 12,000 BTU on the 450 to 550 square foot row, which matches the listing. It is a good fit for an open living room, a primary bedroom with good sun, a studio apartment or a den.
ENERGY STAR publishes this general guide for sizing a room air conditioner by floor area:
| Room Size (sq ft) | Cooling Capacity (BTU/hr) |
|---|---|
| 100 to 150 | 5,000 |
| 150 to 250 | 6,000 |
| 250 to 300 | 7,000 |
| 300 to 350 | 8,000 |
| 350 to 400 | 9,000 |
| 400 to 450 | 10,000 |
| 450 to 550 | 12,000 |
| 550 to 700 | 14,000 |
| 700 to 1,000 | 18,000 |
Adjust for your room: reduce capacity by 10 percent for a heavily shaded room, increase it by 10 percent for a very sunny room, add 600 BTU for each regular occupant beyond two, and add 4,000 BTU if the unit cools a kitchen. Source: ENERGY STAR.
For a typical bedroom under 400 square feet, the 10,000 BTU Whirlpool is usually the better size, because an oversized unit cycles quickly and removes less humidity.
Supplemental Heating
The heater is rated at 10600/8600 BTU depending on supply voltage. That is strong output for a wall unit and enough to warm a medium to large room on a cool spring morning or an early fall night. Whirlpool states that the heat is not meant as a primary source in the coldest months, so in a cold climate, plan to use it alongside your main heating system.
Electric resistance heat costs more per hour than gas heat, so the programmable 24 hour timer is helpful for warming the room only when it is in use.
Power Requirements
The unit requires a special 230-volt/15-amp outlet and has an attached 4.9 foot cord. Whirlpool notes it will not operate with a standard 115V household outlet. Check the receptacle beside the sleeve and confirm the cord will reach it without an extension.
Installation and Sleeve Fit
The universal fit design is the key advantage. The chassis measures 24.2 inches wide, 14.5 inches tall and 20.3 inches deep, and it fits sleeves from 24.5 to 27 inches wide, so it can replace many older units from other brands without changing the sleeve. A trim kit and rear grille are included, and the sleeve is sold separately. At 72.3 pounds, plan on two people for the lift.
Controls and Everyday Use
On-board electronic controls are backed by a remote. You get 3 fan speeds, 4 operation modes, 8-way directional louvers for aiming air, Eco and Sleep functions, and a programmable 24 hour timer for start and stop times. Eco mode saves energy by turning off the compressor once the room reaches the set temperature. The quick-access filter pulls out for cleaning, and a filter light reminds you when it is due.
Noise and Efficiency
Whirlpool lists 57 dB, a moderate level for a 12,000 BTU unit that suits living rooms and works in most bedrooms on Sleep mode. The listed efficiency figure of 9.6 is typical for a conventional heat and cool wall unit.
Care and Maintenance
Wipe the filter clean regularly during summer and again before the first cool spell, since dust reduces airflow in heat mode as well. Keep the rear grille clear of leaves and debris, and check each season that the sleeve still drains to the outside.
Who It Suits Best
The WHAT122-HAW suits medium to large rooms up to 550 square feet with a 230V/15A outlet, particularly when you are replacing an older wall unit and want a chassis that fits a wide range of sleeves. It is less suited to homes with only standard outlets, smart home users, or cold climates that need a primary heat source.
Pros and Cons
| Pros | Cons |
|---|---|
| Fits sleeves 24.5 to 27 inches wide | Needs a 230V/15A outlet |
| Strong 10600 BTU supplemental heat | No Wi-Fi or app control |
| 4.0 out of 5 average rating | Heat is supplemental only |
| Up to 1.6 pints per hour dehumidification | Sleeve sold separately |
| Eco, Sleep and 24 hour timer | Short 4.9 foot cord |
Who Should Buy It
| Who Should Buy It? | Who Should Look Elsewhere? |
|---|---|
| Replacing an older wall unit | Homes with only standard outlets |
| Living rooms up to 550 sq ft | Small bedrooms |
| Rooms that run cool in early fall | Smart home users |
| Buyers who want simple controls | Cold climates needing primary heat |
For more choices, see our picks for the best 12,000 BTU through-the-wall air conditioners with heat and the best 230V through-the-wall air conditioners with heat.
Final Verdict
The Whirlpool WHAT122-HAW is a well-rated, easy-to-fit heat and cool wall unit for medium to large rooms. Its universal sleeve fit and strong supplemental heater make it one of the best replacement choices in the 12,000 BTU class. You can check the current price and details for the Whirlpool 12,000 BTU Wall Air Conditioner with Heat.
Frequently Asked Questions
Does the Whirlpool WHAT122-HAW have heat?
Yes. It provides 10600/8600 BTU of supplemental heat, depending on supply voltage.
What outlet does it need?
It needs a 230V/15A outlet and will not run on a standard 115V household outlet.
What sleeve sizes does it fit?
It fits sleeves from 24.5 to 27 inches wide.
What size room does it cool?
Whirlpool rates it for spaces up to 550 square feet.
About the author
Daniel Brooks is a home cooling editor at WikiCooling, covering window, portable, through-the-wall and mini-split air conditioners, fans, and dehumidifiers. He researches cooling capacity, energy efficiency, noise levels, installation requirements, and buyer feedback to help homeowners choose the right unit for their room size, climate, and budget.