Mobile Home AC Replacement: Costs, Options & What We Recommend

Replacing the air conditioning system in a mobile home or manufactured home is not the same as replacing one in a site-built house. The construction differences, unique ductwork configurations, space constraints, and regulatory requirements mean that mobile home AC replacement requires specialized knowledge and experience. If you live in a mobile or manufactured home in Palm Beach County, this guide covers everything you need to know about your replacement options, realistic costs, common problems, and why choosing the right contractor matters more for your home than for almost any other type of residence.

Why Mobile Homes Have Unique HVAC Needs

Mobile homes and manufactured homes are built to different construction standards than conventional site-built houses, and these differences have a direct impact on how the HVAC system needs to be designed, installed, and maintained.¹

Construction Differences That Affect Cooling

• Thinner walls and less insulation: Mobile homes typically have wall cavities of 2x4 or even 2x3 studs compared to the 2x6 walls common in modern site-built homes. This thinner construction provides significantly less space for insulation, resulting in higher heat gain during Florida's intense summers. Where a site-built home might have R-19 to R-21 wall insulation, a mobile home may have R-7 to R-11.²
• Lower ceiling insulation values: Similarly, mobile home roof and ceiling insulation is typically thinner than in site-built homes, allowing more solar heat to penetrate into the living space.
• Single-pane windows: Many mobile homes, particularly older models, have single-pane windows or lower-quality double-pane windows that allow more heat transfer than the impact-rated double or triple-pane windows found in modern Florida construction.
• Metal exterior: The metal siding and roofing used in many manufactured homes conducts heat more readily than the concrete block, stucco, or insulated siding common in Palm Beach County site-built homes.
• Elevated floor: Mobile homes sit on frames above the ground rather than on a concrete slab, creating a crawl space beneath the home where ductwork typically runs. This elevation exposes the floor and ducts to outdoor temperatures.

What This Means for Your AC System

The combination of these construction factors means that mobile homes in Florida gain heat faster and lose cooling more quickly than site-built homes of similar size. A 1,200-square-foot mobile home may have a cooling load comparable to a 1,600 to 1,800-square-foot site-built home. This has critical implications for system sizing, efficiency selection, and energy costs.

Belly-Board Ductwork: The Hidden Challenge

The ductwork configuration in a mobile home is fundamentally different from a site-built home, and it presents one of the biggest challenges for AC replacement and performance.

How Mobile Home Ducts Work

In most mobile homes, the supply ductwork runs beneath the floor in the crawl space, enclosed by a material called the belly board or belly wrap. This is a flexible membrane that stretches across the bottom of the home's frame, creating an enclosed space where the ducts sit. Supply registers are typically located in the floor rather than in the ceiling or high on walls as in most site-built Florida homes.³

Common Belly-Board Ductwork Problems

• Sagging and damage: Over time, the belly board can sag, tear, or pull away from the frame, exposing the ductwork to outdoor conditions. Animals, moisture, and wind can accelerate this deterioration.
• Duct disconnection: Flexible ductwork under the home can become disconnected from supply boots, meaning cooled air is being blown into the crawl space rather than into your rooms. This is extremely common in older mobile homes and can waste enormous amounts of energy.
• Insufficient insulation: Duct insulation in mobile homes is often minimal, and in Florida's heat, uninsulated or poorly insulated ducts in a crawl space can lose 30 to 40 percent or more of the cooling energy before it reaches the living space.⁴
• Moisture and mold: In Florida's humid climate, temperature differences between the cold supply air and the warm crawl space can cause condensation on and around ductwork, leading to mold growth on the ducts, belly board, and floor structure.
• Restricted airflow: Crushed, kinked, or undersized ducts restrict airflow, reducing system performance and putting strain on the blower motor.

Why Ductwork Must Be Addressed During AC Replacement

Installing a new AC system on top of damaged or deteriorated ductwork is like putting a new engine in a car with flat tires. The system cannot perform as designed because the delivery mechanism is compromised. A responsible HVAC contractor will inspect the ductwork as part of the replacement process and provide honest recommendations about repair or replacement. In many mobile homes over 15 years old, some level of ductwork repair is necessary to achieve proper performance from a new system.

System Types for Mobile Homes

Package Units (Most Common)

The most common AC system type in Florida mobile homes is the package unit, also called a self-contained unit. All components, including the compressor, evaporator coil, condenser coil, and blower, are housed in a single cabinet that sits on a concrete pad outside the home. Supply and return air ducts connect to the unit through openings in the home's floor or wall.⁵

Pros for mobile homes:

• No indoor space required for an air handler, preserving valuable living area in homes where space is limited
• All components are accessible from outside for maintenance and repair
• Simpler installation process since everything is in one unit
• Available in mobile-home-specific configurations with proper connections and sizing

Cons:

• Generally lower maximum efficiency ratings compared to split systems. Most package units top out around SEER 16, while split systems are available up to SEER 24+
• All mechanical components are exposed to outdoor weather, including Florida's salt air, humidity, and hurricane-force winds
• Can be noisier since the compressor is close to living areas

Cost range for mobile home package units in Palm Beach County (2026): $4,500 to $9,000 installed, depending on tonnage and efficiency.

Split Systems

Some mobile homes, particularly newer and larger manufactured homes, use split systems similar to those in site-built houses. The condenser sits outside while an air handler is installed inside the home, typically in a utility closet.

Pros:

• Higher efficiency options available, including variable-speed systems
• Better humidity control with access to the full range of modern compressor technologies
• Quieter indoor operation since the compressor is outside

Cons:

• Requires indoor space for the air handler, which can be challenging in mobile homes with limited closet space
• Installation is more complex and typically more expensive
• Not all mobile home configurations can accommodate a split system without modifications

Cost range for mobile home split systems in Palm Beach County (2026): $6,000 to $13,000 installed.

Ductless Mini-Split Systems

Mini-splits are an increasingly popular option for mobile homes, either as a whole-home solution or to supplement an existing system.

Pros for mobile homes:

• Eliminates all ductwork issues, which is a major advantage given the common belly-board problems in mobile homes
• Very high efficiency ratings, with many models exceeding SEER 20
• Zone-by-zone temperature control
• No crawl space ductwork to maintain or repair

Cons:

• Wall-mounted indoor units are visible in every served room
• Multiple zones for a whole-home installation can be expensive
• Some mobile home communities have aesthetic restrictions on exterior equipment placement

Cost range for mini-splits in mobile homes (2026): $3,000 to $6,000 per zone installed. A three-zone system for a typical mobile home runs $8,000 to $14,000.⁶

Common Problems with Mobile Home AC Systems

In our decades of servicing mobile homes throughout Palm Beach County, these are the issues we encounter most frequently:

Oversizing

Mobile home AC systems are frequently oversized, often because the original system was selected based on square footage without accounting for the home's specific construction characteristics. An oversized system short cycles, running briefly before shutting off, and never removes enough humidity from the air. In Florida's climate, this leads to a home that feels clammy and uncomfortable even when the thermostat reads 74 degrees.⁷

Undersized Return Air

Many mobile homes have inadequate return air pathways. If interior doors are closed and the return air grille is in a central hallway, rooms can become pressurized, forcing conditioned air out through gaps and cracks while drawing in hot, humid outdoor air. The result is poor cooling in bedrooms and excessive energy waste.

Thermostat Location

In many mobile homes, the thermostat is located in a hallway near the return air grille, which may not be representative of temperatures throughout the home. If the hallway is naturally cooler or warmer than the living areas or bedrooms, the thermostat will cycle the system based on inaccurate information.

Electrical Issues

Older mobile homes may have electrical panels and wiring that are not adequate for modern, higher-capacity AC equipment. Upgrading the electrical service may be necessary as part of an AC replacement, adding to the project cost but improving safety and allowing for proper equipment operation.⁸

Sizing Your Mobile Home AC Correctly

Proper sizing is critical in any home, but it is especially important in mobile homes where the margin for error is smaller due to the construction factors described above.

The Manual J Requirement

A proper Manual J load calculation should be performed for every mobile home AC replacement. This calculation accounts for the specific insulation values, window types, orientation, and construction characteristics of your manufactured home. Generic sizing rules like 400 to 500 square feet per ton are unreliable for mobile homes because their thermal characteristics differ so significantly from site-built construction.⁹

Common Sizing for Florida Mobile Homes

While every home is different and a load calculation is essential, typical AC sizing for Florida mobile homes generally falls in these ranges:

• Single-wide (600-900 sq ft): 2 to 2.5 tons
• Single-wide (900-1,100 sq ft): 2.5 to 3 tons
• Double-wide (1,200-1,600 sq ft): 3 to 4 tons
• Triple-wide or large double-wide (1,600-2,000+ sq ft): 4 to 5 tons

These are rough guidelines only. The actual requirement can vary significantly based on insulation quality, window area, sun exposure, and other factors that a Manual J calculation captures.

Brand Recommendations for Mobile Homes

Not all AC brands offer equipment specifically designed for mobile home applications. Look for manufacturers who produce mobile-home-rated package units and air handlers designed to fit the space and connection requirements of manufactured housing.

• Goodman / Daikin: Offers a wide range of mobile-home-specific package units and air handlers at competitive prices. Their GPG and GPH series package units are among the most commonly installed in Florida mobile homes. Good parts availability and widespread contractor familiarity.
• Rheem: Produces reliable package units suitable for mobile home applications with good efficiency options. Their Classic Plus series offers solid value for manufactured housing.
• Revolv (by Allied Air): Specifically designed for manufactured housing. These units are built to HUD specifications for mobile homes and offer straightforward replacement with proper connections and sizing. Budget-friendly option with decent reliability.
• Coleman (by Johnson Controls): Offers mobile-home-rated package units with good build quality. Mid-range pricing with reliable performance in Florida's climate.
• Mitsubishi and Daikin (mini-splits): For homeowners choosing the ductless route, these brands offer the best combination of efficiency, humidity control, and reliability for Florida applications.¹⁰

Permits for Mobile Home AC Replacement in Palm Beach County

Mobile home AC replacement in Palm Beach County requires permits just like site-built homes, but there are additional considerations:

• Mechanical permit: Required for any AC system replacement. Your contractor pulls this permit.
• HUD compliance: Manufactured homes built after June 15, 1976 must comply with HUD standards, and any modifications, including HVAC replacement, should maintain compliance.
• Mobile home park requirements: Some mobile home communities have additional requirements or approval processes for exterior equipment changes. Check with your park management before scheduling installation.
• Wind load compliance: In Palm Beach County's hurricane zone, outdoor equipment must be properly secured to withstand high winds. Package units should be strapped or anchored according to local code requirements.¹¹

Why You Need a Specialist Contractor

This is perhaps the most important point in this entire guide. Mobile home HVAC work requires a contractor who has specific experience with manufactured housing. Here is why:

• Different equipment: Mobile homes often require specific models designed for manufactured housing applications. A contractor who only works on site-built homes may install standard residential equipment that does not properly fit or connect to your home's ductwork and utility connections.
• Belly-board expertise: Inspecting and repairing belly-board ductwork is a specialized skill. A contractor unfamiliar with manufactured home construction may not know how to properly access, evaluate, or repair the underfloor duct system.
• Space constraints: Mobile homes have tighter mechanical spaces, lower ceilings, and more restricted access than site-built homes. Experienced mobile home HVAC technicians know how to work efficiently in these conditions.
• Sizing knowledge: The thermal characteristics of manufactured homes differ significantly from site-built construction. A contractor experienced with mobile homes understands these differences and will size the system appropriately.
• Code familiarity: HUD standards, local mobile home park requirements, and Florida building code provisions specific to manufactured housing all affect the installation process. A specialist knows these requirements.

Questions to Ask Your Contractor

• How many mobile home AC installations have you completed in the past year?
• Do you carry mobile-home-specific equipment or will you need to order it?
• Will you inspect the belly-board ductwork before recommending a system?
• Will you perform a Manual J load calculation specific to my manufactured home?
• Are you familiar with Palm Beach County permit requirements for mobile homes?

If the contractor cannot answer these questions confidently, keep looking. A general HVAC contractor who occasionally works on mobile homes is not the same as one who has deep experience with manufactured housing.¹²

What to Expect Cost-Wise

Here is a realistic overview of total project costs for mobile home AC replacement in Palm Beach County in 2026:

• Basic package unit replacement (same size, standard efficiency): $4,500 to $7,000
• Mid-range package unit with improved efficiency: $6,500 to $9,000
• Split system installation: $6,000 to $13,000
• Ductless mini-split (whole home, 3-4 zones): $8,000 to $14,000
• Ductwork repair (add to above): $800 to $3,000 depending on extent
• Belly-board repair (add to above): $500 to $2,000
• Electrical upgrades if needed (add to above): $500 to $2,000

These costs include equipment, labor, standard materials, and permit fees. Ductwork, belly-board, and electrical work are additional costs that depend on the condition of your specific home.

Making the Right Choice for Your Mobile Home

The best AC replacement strategy for your mobile home depends on several factors:

• If your ductwork is in good condition: A high-efficiency package unit or split system is usually the most cost-effective choice.
• If your ductwork is severely damaged: Consider a ductless mini-split system that eliminates the ductwork entirely, or factor in the cost of complete duct replacement.
• If you plan to stay in the home long-term: Investing in higher efficiency and ductwork improvements pays off through lower monthly bills and better comfort.
• If budget is the primary concern: A standard-efficiency package unit replacement is the most affordable option and will still provide reliable cooling.

At Central Air Systems, we have been installing and servicing AC systems in mobile homes and manufactured homes throughout Palm Beach County since 1991. As a family-owned company, we understand that mobile home owners deserve the same level of expertise and care as any other homeowner. We carry mobile-home-specific equipment, our technicians are experienced with belly-board ductwork, and we perform proper load calculations for every manufactured home we work on. Call us at 561-585-6819 or visit centralairsfl.com to schedule a free evaluation of your mobile home's cooling system and get an honest assessment of your options.