Quick answer
A packaged HVAC unit is a heating and cooling system built into one outdoor cabinet, holding the compressor, both coils, the blower and often a gas burner, that connects to the home's ducts through a wall or roof.
Federal rules call it a single-package unit. Common forms are the gas pack (gas heat plus electric cooling), the packaged heat pump and the packaged air conditioner. On commercial roofs it is called a rooftop unit.
Quick facts
The key facts about Packaged HVAC Unit, with sources:
Key takeaways
- Everything is in one outdoor box; nothing but ducts and a thermostat is inside.
- It suits homes with no basement, attic or closet space for a furnace.
- Packaged units have lower federal minimums than split systems 1.
- Ducts pass through an outside wall or the roof, where sealing matters a lot.
- Refrigerant is sealed in at the factory, so there is no long line set to leak.
What a packaged unit is
Picture a split system with the indoor half moved outside and bolted into the same cabinet. That is a packaged unit. The cabinet holds the compressor, the outdoor coil, the indoor coil, the blower, the filter rack in many models, and in a gas pack a gas burner and heat exchanger.
Two large duct openings on the side or bottom connect to the home's supply and return ducts.
On a slab house the ducts usually come through an outside wall into the attic or a soffit. On a manufactured home they go under the floor.
On many commercial buildings the unit sits on the roof over a curb.
Federal efficiency rules give these "single-package units" their own product classes, separate from split systems 1.
Air and refrigerant paths in one cabinet
- House air → return duct → through the wall or roof → filter → blower inside the cabinet
- Cooling: blower → cold indoor coil → supply duct → rooms
- Refrigerant: indoor coil → compressor → outdoor coil (heat out) → metering device → indoor coil, all inside the cabinet
- Gas pack heating: burner → heat exchanger → blower pushes air over it → supply duct
- Heat pump heating: reversing valve swaps coils; backup strips may run in the supply section
- Exhaust (gas pack) leaves through a vent hood on the cabinet; condensate drains outside
How a packaged unit works
Cooling works like any air conditioner. The only difference is that both coils share one box, with a wall inside the cabinet separating the indoor air side from the outdoor air side.
Heating depends on the type. A gas pack has a weatherized gas furnace section built in. A packaged heat pump heats by reversing the refrigerant flow, with electric strips for backup. A dual-fuel package combines a heat pump with a gas section.
Because the indoor air path sits outside, the cabinet must be well sealed and insulated. Leaks in the cabinet or the duct connections pull in outdoor air and lose conditioned air.
Types of packaged units
| Type | Heats with | Cools with | Federal floor |
|---|---|---|---|
| Packaged air conditioner | Electric strips or nothing | Refrigerant cycle | 13.4 SEER2 1 |
| Gas pack (gas/electric) | Weatherized gas furnace | Refrigerant cycle | 13.4 SEER2 + 81% AFUE 1 |
| Packaged heat pump | Heat pump + strips | Same heat pump | 13.4 SEER2, 6.7 HSPF2 1 |
| Dual-fuel package | Heat pump, then gas | Heat pump | Heat pump and AFUE floors |
| Rooftop unit (commercial) | Gas or heat pump | Refrigerant cycle | Commercial rules, not 10 CFR 430.32 |
Worked example: packaged vs split floors in a hot state
Same cooling job, two configurations, installed in Arizona (Southwest region). Thresholds from 10 CFR 430.32(c), products made from 1 January 2023 1.
| Requirement | Split AC, under 45,000 BTU/h | Single-package AC |
|---|---|---|
| National SEER2 floor | 13.4 | 13.4 |
| Southwest SEER2 floor | 14.3 | No separate figure in the codified table; 13.4 applies |
| Southwest EER2 floor | 11.7 (if under 15.2 SEER2) or 9.8 | 10.6 |
| Cooling energy for 24 million BTU at the floor | 24,000,000 ÷ 14.3 ≈ 1,678 kWh | 24,000,000 ÷ 13.4 ≈ 1,791 kWh |
A packaged AC built to the floor can use about 7% more electricity than a split AC built to the Southern floor for the same assumed load. Many packaged units are rated above the floor, so compare the actual SEER2 on each quote. The single-package row is reported as codified in the current eCFR text.
Where packaged units are found
- On a concrete pad beside slab-on-grade homes, common across the South and Southwest.
- Beside manufactured homes, with ducts under the floor.
- On roofs of homes and small commercial buildings.
- On the data plate: one model number for the whole system, plus the gas input if it is a gas pack.
- On the AHRI directory, listed as single-package equipment 3.
Pros and cons
What it does well
- Frees indoor space; nothing in a closet or attic.
- Refrigerant circuit sealed at the factory, so no field line set.
- All service happens outside, without entering the home.
- One unit to replace instead of two halves to match.
Where it falls short
- Lower federal floors mean some units are less efficient than split options 1.
- The whole system, including the blower and heat section, sits in the weather.
- Duct penetrations through walls or roofs must be sealed well.
- Fewer high-efficiency and variable-speed choices than split systems.
Where packaged units fall short
The duct connection is the weak spot. Supply and return ducts run from the cabinet through an outside wall. If the joints, the transition boxes or the cabinet itself leak, the unit can pull in hot, dusty outdoor air. A duct leakage test catches this.
Packaged units also give you fewer choices at the top of the efficiency range. If you want a very high SEER2 or a cold-climate heat pump, a split system or a mini-split may offer more models. ENERGY STAR's cold-climate list does include single-package units at 8.1 HSPF2 or more 2.
Cost drivers, lifespan and warranty
What changes the price: capacity, gas pack vs heat pump vs dual fuel, efficiency tier, a crane for roof units, new curbs or pads, duct transitions, electrical and gas work, and permits.
Because the whole system lives outdoors, sun, salt air and storms can shorten its life, especially near the coast. Cabinet rust and hail damage are common reasons to replace.
Warranties cover the whole unit under one model number, with heat exchanger terms set by the maker. HyreHVAC does not print unit prices without enough local quotes; the replacement calculator gives an estimate.
Replacing a packaged unit
- Load calculation and duct check 7.
- Confirm the new unit's duct openings line up with the old ones, or plan a transition.
- Permits for mechanical, electrical and gas work.
- Recover refrigerant from the old unit (EPA 608 certified) 5; disconnect gas and power.
- Set the new unit on a level pad or roof curb (crane for roofs).
- Seal the duct connections, connect gas and power, start up and test.
- Inspection.
Upkeep for a unit that lives outside
- Find the filter: it may be in the unit or in a return grille inside the home. Change it on schedule.
- Keep plants, fences and debris back from all sides of the cabinet.
- Make sure the condensate drain outlet is clear.
- After storms, look for hail damage or loose panels and call if you see any.
- Book a yearly check, which on a gas pack includes the burner, heat exchanger and vent 6.
Warning signs
- Dust or a hot, musty smell from vents, which suggests a leaking duct connection.
- Water inside the home near where ducts enter.
- Burner rumble or soot around the vent hood on a gas pack.
- Rust holes in the cabinet or base pan.
- Weak cooling with ice on the coil; refrigerant work requires a certified technician 5.
Rules for packaged units
DOE (10 CFR 430.32(c)), from 1 January 2023. Single-package air conditioners: 13.4 SEER2. Single-package heat pumps: 13.4 SEER2 and 6.7 HSPF2. In the Southwest, single-package air conditioners must also meet 10.6 EER2. The codified regional table lists no separate Southeast or Southwest SEER2 for single-package ACs 1.
Gas section. Weatherized gas furnaces made from 1 January 2015 need 81% AFUE. The 95% AFUE rule for 2028 covers non-weatherized and mobile home gas furnaces, not weatherized ones 1.
EPA. New residential systems, including unitary packaged ones, must use a refrigerant under 700 GWP from 1 January 2025 4.
Packaged unit vs split system vs mini-split
| Feature | Packaged unit | Split system | Mini-split |
|---|---|---|---|
| Cabinets | One outdoors | One out, one in | One out, heads in |
| Ducts | Yes | Yes | No |
| Indoor space | None | Closet, attic or basement | Wall space |
| Heat pump floor | 13.4 SEER2 / 6.7 HSPF2 | 14.3 SEER2 / 7.5 HSPF2 | 14.3 SEER2 / 7.5 HSPF2 |
Common misconceptions
- Myth Packaged units are only for businesses.
- Reality Many homes, especially slab and manufactured homes, use them.
- Myth The 2028 95% AFUE rule covers gas packs.
- Reality It covers non-weatherized and mobile home gas furnaces; gas packs use weatherized furnaces 1.
- Myth A packaged unit has no filter.
- Reality It does; it may be in the cabinet or in a return grille indoors.
Why packaged units cluster in the Sun Belt
Packaged units are common where houses sit on slabs and winters are mild, such as Arizona, Texas and Florida.
There, the Southwest EER2 floor of 10.6 for packaged ACs applies in Arizona and California, while Texas and Florida use the national 13.4 SEER2 floor for packaged ACs 1. Long cooling seasons make a higher-rated unit worth pricing.
When a packaged unit makes sense
A packaged unit fits when there is no good indoor spot for equipment, when the existing ducts were built for one, or when you want all service outside. It makes less sense if you want the highest efficiency or have room for a split system.
Next step: price both options with the AC sizing calculator and line up bids in the quote comparison tool.
Questions about Packaged HVAC Unit
What is a packaged HVAC unit?
It is a heating and cooling system with every major part in one outdoor cabinet: compressor, both coils, blower and often a gas burner. It connects to the home's ducts through a wall or roof, so nothing but ducts and a thermostat sits indoors.
What is a gas pack?
A gas pack is a packaged unit with a gas furnace section for heat and an air conditioner for cooling. Its furnace is a weatherized type with a federal floor of 81% AFUE.
Is a packaged unit better than a split system?
Neither wins everywhere. A packaged unit saves indoor space and keeps service outside. A split system usually offers higher efficiency choices and keeps the blower out of the weather. The house layout often decides it.
Where is the filter on a packaged unit?
Either in a slot inside the cabinet or in a return-air grille inside the house. Look for a large grille on a wall or ceiling first. If there is no filter there, check the unit's access panels or ask your technician.
What SEER2 must a packaged unit meet?
Packaged air conditioners and heat pumps must meet 13.4 SEER2. Packaged heat pumps also need 6.7 HSPF2. Packaged ACs installed in the Southwest must meet 10.6 EER2 as well.
Do packaged units last as long as split systems?
They can, but all their parts sit outdoors, so sun, salt air and hail can wear them faster in some places. Regular cleaning and quick repair of cabinet damage help.
Can a packaged unit be a heat pump?
Yes. Packaged heat pumps heat and cool with one refrigerant system and usually have electric backup strips. ENERGY STAR packaged heat pumps need at least 15.2 SEER2, 10.0 EER2 and 7.2 HSPF2.
Why does dust come out of my vents with a packaged unit?
Often because the supply or return duct connection at the wall or roof is leaking and pulling in outdoor air. A technician can test and seal the connections and the cabinet.
Sources
- eCFR, 10 CFR 430.32, Energy and water conservation standards (version of 1 September 2026), retrieved .
- ENERGY STAR, Air Source Heat Pumps Key Product Criteria, retrieved .
- AHRI Directory of Certified Product Performance, retrieved .
- U.S. EPA, Technology Transitions HFC Restrictions by Sector, retrieved .
- U.S. EPA, Section 608 Technician Certification, retrieved .
- U.S. EPA, Carbon Monoxide's Impact on Indoor Air Quality, retrieved .
- ACCA, Manual J Residential Load Calculation (8th Edition), retrieved .
Expert review
Written by the HyreHVAC Research team. Not yet reviewed by an outside expert. We say so rather than imply a review that has not happened; see our editorial policy.
How the numbers were checked: Single-package floors and the regional table copied from the eCFR text of 10 CFR 430.32(c) and (e); the empty Southern SEER2 cells for single-package ACs are reported as codified. ENERGY STAR and EPA criteria read 10 October 2026.
Suggest a correction. We fix errors and say what changed.