Coleman | Mach 3 Plus RV Air Conditioner | 38203-066 | 13,500 BTU | White

Cool your RV reliably with the Coleman Mach 3 Plus RV Air Conditioner (Part #38203-066) in textured white — the preferred 13,500 BTU mid-range choice from Coleman Mach. With 320 CFM of airflow matching the bigger Mach 15, R-32 next-generation refrigerant, and the same proven medium-profile design that fits any standard 14"×14" roof opening, the Mach 3 Plus is the right answer for typical mid-size to large RVs in moderate to warm climates.

13,500 BTU — The Preferred Mid-Range Choice

The Mach 3 Plus delivers 13,500 BTU of cooling — substantial output for most RV cooling scenarios:

• Mid-size to large travel trailers and fifth wheels
• Smaller motorhomes
• RVs in moderate to warm climates
• Setups with typical cooling loads (well-insulated, normal sun exposure, average size)

The "Plus" designation reflects this unit's upgrades over the original Mach 3 — larger coils, raised lance fins, gas-flux brazed joints, and R-32 refrigerant. The result: better cooling performance and durability than the predecessor unit while keeping the same form factor and 14"×14" mounting standard.

320 CFM Airflow — Matches the Mach 15

One of the Mach 3 Plus's standout specs: it delivers 320 CFM of evaporator airflow — the same airflow rating as the much larger 15,000 BTU Mach 15. That airflow capacity makes the Mach 3 Plus equally effective in both ducted AND non-ducted ceiling assemblies. Strong airflow is what allows the unit to push cool air through long ducted runs while still maintaining performance in non-ducted installations.

R-32 Next-Generation Refrigerant

The current-production Mach 3 Plus uses R-32 refrigerant — the next-generation low-GWP refrigerant that replaces R-410A in all new Coleman Mach production. R-32 offers meaningful improvements:

• Approximately 70% lower global warming potential than R-410A (GWP ~675 vs ~2,088)
• Zero ozone depletion potential
• Improved energy efficiency in many operating conditions vs R-410A
• Meets 2025 EPA AIM Act refrigerant requirements

The 38xxx prefix across all current Coleman Mach models indicates R-32 charge. Note: R-32 is classified as A2L (mildly flammable) — service must be performed by a qualified technician using appropriate equipment.

Direct Replacement for R-410A Predecessors

The 38203-066 is the direct replacement for the prior R-410A generation Mach 3 Plus white models. Cross-reference part numbers:

• Replaces 48203-066
• Replaces 48203-666

If your existing Mach 3 Plus has either of those part numbers, this 38203-066 is the modern R-32 successor. The shroud dimensions, mounting footprint, and ceiling assembly compatibility are identical to the prior generation — making this a clean drop-in replacement.

Built for Years on the Road

The Mach 3 Plus shares Coleman Mach's engineering discipline across the lineup:

• All-copper tubing throughout the refrigerant circuit — no aluminum compromises
• Gas-flux brazed joints — higher integrity than standard soldering, resists vibration fatigue and thermal cycling stress
• Large evaporator and condenser coils with raised lance-style fins — maximizes heat transfer surface area
• Medium-profile shroud (13.8" tall) — lower aerodynamic drag than older standard-height units

Available in Textured Black Too

This is the textured white color variant. If you prefer a textured black finish for your RV roof, the same Mach 3 Plus is available as the Coleman Mach 3 Plus 38203-069 (Textured Black) — identical specs and performance, just darker shroud color.

Mach 3 Plus vs. Mach 15 — Which Should You Pick?

The Mach 3 Plus and Coleman Mach 15 (38204-069) share the same medium-profile platform, same 320 CFM airflow, same R-32 refrigerant, and same 14"×14" mounting standard. The key difference: BTU capacity.

• Mach 3 Plus (13,500 BTU) — the right choice for mid-size to large RVs with typical cooling loads in moderate to warm climates; draws 13.1 amps
• Mach 15 (15,000 BTU) — the right choice for large motorhomes, long fifth wheels, heavy cooling loads, or extreme heat climates (dark roof, large windows, multiple slide-outs); draws 13.9 amps

For most RV owners not regularly camping in extreme summer heat, the Mach 3 Plus is more than adequate cooling. The Mach 15's additional 1,500 BTU advantage matters most when sustained pull-down in high ambient temperatures or large/poorly-insulated spaces is needed.

Optional Heat Strip

For shoulder-season comfort without firing up the furnace, a compatible resistance heater assembly (sold separately) drops into the Mach 3 Plus to add electric heat capability. The unit itself is cool-only.

⚠️ Ceiling Assembly & Thermostat Sold Separately

The 38203-066 is the upper (rooftop) unit only. A complete installation requires:

• A compatible ceiling assembly — ducted or non-ducted (sold separately)
• A compatible thermostat / wall control (sold separately)

The unit ships with a pre-installed roof compression gasket on the base — no additional roof sealant required for the rooftop unit itself. Professional installation recommended given the 79.5 lb unit weight, electrical connections, and need for a secure leak-free roof mount.

⚠️ Important Shipping Notes

• Freight items cannot be returned — confirm fitment, dimensions, and configuration before ordering

What's Included

• 38203-066 Rooftop Air Conditioner (upper unit)
• Pre-installed roof compression gasket
• Mounting hardware
• Owner's documentation

Must Be Purchased Separately

• Ceiling assembly (ducted or non-ducted)
• Thermostat / wall control
• Optional resistance heat strip assembly

Key Features

• 13,500 BTU cooling capacity — the preferred mid-range choice
• 320 CFM evaporator airflow — matches the bigger Mach 15
• R-32 next-generation refrigerant — 70% lower GWP vs R-410A
• All-copper tubing with gas-flux brazed joints
• Large coils with raised lance fins for maximum heat transfer
• Medium profile — 13.8" tall, more aerodynamic than older standard-height units
• Ducted AND non-ducted compatible
• 14" × 14" standard roof opening — fits all standard RV roof vent openings
• Pre-installed roof compression gasket
• Direct R-32 replacement for 48203-066 and 48203-666 R-410A models
• Textured white finish
• Optional heat strip compatibility (sold separately)
• Backed by a 2-year limited manufacturer parts and labor warranty

Specifications

• Brand: Coleman Mach / Airxcel
• Series: Mach 3 Plus
• Part Number: 38203-066
• Replaces (R-410A predecessors): 48203-066, 48203-666
• Function: AC only (cool only)
• BTU Capacity: 13,500 BTU
• Voltage: 115 VAC
• Frequency: 60 Hz, single phase
• Cooling Amps: 13.1 A
• Evaporator Airflow: 320 CFM
• Refrigerant: R-32 (Low-GWP, A2L class)
• Tubing: All-copper with gas-flux brazed joints
• Coil Design: Large evaporator and condenser coils with raised lance fins
• Heat Pump: No (cool only)
• Profile: Medium profile
• Shroud Dimensions: 13.8" H × 26.1" W × 38.0" L
• Roof Opening: 14" × 14" standard
• AC System: Ducted or non-ducted
• Color/Finish: Textured white
• Weight: 79.5 lbs
• Roof Gasket: Pre-installed compression gasket included
• Warranty: 2-year limited manufacturer warranty (parts and labor)