🌀 Understanding the Two Types of Through-the-Wall Units
If you're shopping for a through-the-wall air conditioner, you'll quickly encounter two major categories:
1️⃣ Straight Cooling Units — These only provide air conditioning.
2️⃣ Heat Pump Units — These cool and also provide heating.
The Amana PBH092J12AA is a great example of a through-the-wall heat pump unit. But is heat pump functionality worth the extra cost for your situation? Let Mike Sanders break it down in detail.
🔢 How a Heat Pump Works vs. Straight AC
Both systems use refrigeration technology, but with one key difference:
| Feature | Straight Cooling | Heat Pump |
|---|---|---|
| Cooling Function | Yes | Yes |
| Heating Function | No | Yes |
| Refrigerant Reverses | No | Yes (via reversing valve) |
| Year-Round Use | Summer only | Summer + Winter |
Heat pumps reverse the refrigerant flow to extract heat from outdoor air and bring it inside during colder months.
Reference: Energy.gov Heat Pump Systems Explained
🌞 Benefits of Heat Pump Through-the-Wall Units
🔺 Year-Round Comfort
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Provides both heating and cooling from a single device.
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No need for separate space heaters or furnace supplements.
💲 Energy Efficiency
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Heat pumps often use 30%-50% less electricity for heating compared to resistance electric heat.
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Reduce winter energy bills in moderate climates.
📚 Simplified Installation
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One unit, one sleeve, one electrical hookup.
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No additional ductwork or gas lines required.
🏡 Ideal for Zone Heating
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Great for isolated rooms, additions, sunrooms, or in-law suites.
Reference: Department of Energy: Heat Pump Advantages
🌬️ Limitations of Heat Pump Units
Heat pumps are not perfect for every situation. Understanding their weaknesses ensures you're making the right call.
🌨 Performance in Cold Climates
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Heat pump efficiency drops as outdoor temperatures approach freezing.
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At extreme cold (below 25°F), backup heat may be necessary.
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Many through-the-wall models include built-in auxiliary electric heating.
🌐 Upfront Cost
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Heat pump units are typically 20%-40% more expensive than straight cooling models.
🔦 Heat Output Limits
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Most through-the-wall heat pumps max out around 8,000-12,000 BTU heating capacity.
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May not fully replace whole-home heating in harsh climates.
Reference: HVAC.com: Heat Pump Downsides Explained
🌍 Straight Cooling Only: When It Still Makes Sense
📆 Short Summer-Only Seasons
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If your region only sees hot weather for a few months each year, heating functionality may be unnecessary.
🏫 Buildings With Central Heat
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Homes with gas furnaces, radiant systems, or baseboard heating already have adequate winter coverage.
📅 Lower Budget Upfront
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Straight cooling units are more affordable upfront.
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Simplifies installation if only occasional cooling is needed.
🔋 Electrical Considerations
Many through-the-wall heat pumps (like the Amana PBH092J12AA) operate on standard 115V circuits:
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No special 220V wiring necessary.
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Simplifies retrofit installs.
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Matches typical U.S. residential outlets.
However, larger capacity heat pump models (over 12,000 BTU) may require dedicated 220V circuits.
Reference: Amana PBH092J12AA Specs
📈 Energy Cost Comparison
| Cost Category | Heat Pump | Straight Cooling + Electric Heat |
| Cooling | Similar | Similar |
| Heating | Much lower (in moderate climates) | Higher (electric resistance heat is expensive) |
| Total Year-Round Energy | Lower overall | Higher overall |
Reference: Energy Star Cost Savings Guide
📊 Climate Zones: The Deciding Factor
Ideal Climates for Heat Pumps:
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Southeast U.S.
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Pacific Northwest
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Coastal California
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Mid-Atlantic
Climates Where Heat Pumps Struggle:
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Upper Midwest (Minnesota, Wisconsin)
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Northeast (Maine, Vermont)
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Mountain regions
Heat pumps thrive in temperate zones with mild winters. In freezing climates, straight cooling with supplemental heat often makes more sense.
Reference: ASHRAE Climate Zone Map
📅 Installation Cost Comparison
| Cost Component | Heat Pump Model | Straight Cooling Model |
| Unit Price | Higher | Lower |
| Wall Sleeve | Same | Same |
| Electrical Wiring | Similar | Similar |
| Long-Term Value | Higher (dual use) | Limited |
🏡 Real-World Use Cases
Heat Pump Through-the-Wall AC Ideal For:
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Apartments needing supplemental heat
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Home offices for year-round comfort
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Sunrooms or additions without central heat
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Rental properties adding efficient heating
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Elderly suites or in-law units
Straight Cooling Through-the-Wall AC Ideal For:
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Summer vacation homes
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Rented units with existing central heat
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Bedrooms with existing furnace
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Budget-sensitive installations
🌟 Mike Sanders' Rule of Thumb
"If your winters stay above 25°F most of the season, and you want one efficient unit to handle heating and cooling — go heat pump. If you're only concerned with beating the summer heat or you already have central heating — straight cooling works just fine."
In the next topic we will know more about: How Much Does It Cost to Install a Through-the-Wall AC with Heat Pump? (2025 Pricing Guide)
