Dometic Fresh Jet 5 vs Penguin 2 Air Conditioner: Complete Installation Guide for RVs

Short Answer

The Dometic Fresh Jet 5 is significantly quieter than the Penguin 2 - about 6-8 decibels lower, which represents a significant reduction in perceived noise level. However, it's not a plug-and-play replacement. The Fresh Jet 5 has a different footprint, mounting system, and electrical requirements that will require modifications to your RV. The amp draw is actually slightly higher at startup (see manufacturer specs for exact amperage vs Penguin 2), but it cycles less frequently due to better efficiency. You'll need to budget $1,800-$2,200 for the unit plus installation costs ranging from $800-$1,500 depending on the modifications required.

Understanding the Problem

The Penguin 2 has been a reliable workhorse for years, but its age shows in both noise levels and energy efficiency. Running at higher decibel levels during operation (see manufacturer specs for exact measurements), it can be quite intrusive, especially for neighboring campers. The Fresh Jet 5 addresses this with improved compressor isolation and redesigned fan systems that typically operate at 60-64 decibels under normal conditions.

The compatibility issue stems from Dometic's complete redesign of the mounting system. The Penguin 2 uses a traditional shroud (dimensions available in manufacturer specifications - verify compatibility before purchase) with specific bolt patterns, while the Fresh Jet 5 has a more aerodynamic profile with different dimensions (see manufacturer specs) with different mounting points. Additionally, the Fresh Jet 5 requires a different electrical setup - it needs both 120V AC power and 12V DC for the control system, whereas your Penguin 2 uses AC power with 12V for thermostat controls.

The amp draw difference is nuanced. While the Fresh Jet 5 initially draws more power during startup, its variable-speed compressor and improved insulation mean it doesn't cycle on and off as frequently. Over a full day of use, many RVers report 10-15% lower overall power consumption, which is significant when boondocking.

What You'll Need

For this upgrade, you'll need several components beyond just the Fresh Jet 5 unit itself. The primary requirement is the appropriate adapter kit for your specific RV model (verify part number and current pricing with dealer) and includes the necessary mounting hardware to bridge the size difference between your old Penguin 2 footprint and the new unit.

Electrical components include a 12V DC power supply if your RV doesn't already have one routed to the roof, appropriately sized wire for the DC connection (gauge depends on amperage and run length), and potentially a new thermostat compatible with the Fresh Jet 5's digital control system. You'll also need marine-grade sealant like Dicor or Eternabond tape, stainless steel screws, and possibly additional roof reinforcement materials if your current mounting area shows any weakness.

Tools required include a drill with various bits, a jigsaw for any roof modifications, wire strippers and crimpers, a multimeter for electrical testing, and basic hand tools. Don't forget safety equipment - a stable ladder system and non-slip shoes for roof work are essential.

How to Fix It

SAFETY WARNING: Working on an RV roof presents serious fall hazards. Use proper ladder safety techniques, have a spotter present, wear non-slip shoes, and avoid working during windy conditions or when the roof is wet. Consider using a safety harness system. Never work alone on the roof.

Start by carefully removing your Penguin 2, taking detailed photos of the electrical connections before disconnecting anything. Clean the roof area thoroughly and inspect for any soft spots or damage that should be addressed before installing the new unit. The Fresh Jet 5's mounting pattern is different, so you'll likely need to drill new holes - use the adapter kit's template to ensure proper placement.

The electrical upgrade is the most complex part of this installation. Run 12V DC power from your distribution panel to the roof location if it's not already there. The Fresh Jet 5's control system requires constant 12V power even when the AC isn't running. Connect the AC power leads to your existing AC circuit, but you'll need to install the new digital thermostat inside your RV, which may require running new thermostat wire.

Seal everything meticulously - roof leaks from improper AC installation are among the most expensive RV repairs. Use a high-quality sealant around the base and ensure the gasket is properly positioned. Test the system thoroughly before finalizing the installation, checking both cooling performance and all electrical functions.

Allow 6-8 hours for a careful DIY installation, or 4-5 hours for an experienced technician. The learning curve is moderate - it's more involved than a simple AC replacement but manageable for someone comfortable with basic electrical work and roof access.

Leave It to the Experts

Consider professional installation if you're uncomfortable working on your RV's roof or dealing with both 120V and 12V electrical systems. The combination of height, electrical complexity, and waterproofing requirements makes this a job where mistakes can be costly. Professional installation typically runs $800-$1,500 depending on your location and any additional electrical work needed.

Many RV service centers offer package deals that include the Fresh Jet 5, adapter kit, and installation for around $2,800-$3,200 total. This often includes a warranty on both the unit and installation work. Some mobile RV technicians specialize in AC replacements and can perform the work at your location, though you'll pay a premium for this convenience.

If you're handy but want guidance, many RV service centers will perform a consultation where they assess your specific installation requirements and provide detailed instructions for around $100-$150. This can help identify any unique challenges with your particular RV model before you begin the work yourself.