Buying a used roof air conditioner for an R V can offer substantial savings, but it requires careful evaluation of condition, compatibility, and installation. This guide covers how to assess value, select the right unit, and install it safely and efficiently for reliable climate control on the road.
Key Consider When Buying A Used RV Roof Air Conditioner
Before purchasing, identify the unit’s brand, model, and BTU rating. Common RV units include Dometic and Coleman Mach, with 13,500 to 15,000 BTU models being typical for many coaches. Check the roof opening size, usually 14×14 inches or similar, and ensure the new unit will fit without extensive modification. Consider the following:
- BTU and cooling capacity: Match the unit to the RV’s square footage and insulation level. Overestimating capacity wastes energy; underestimating leaves the space uncomfortable.
- Voltage and amperage: Most RV ACs run on 120V and require a dedicated circuit. Verify electrical compatibility with the RV’s converter or inverter system.
- Brand availability and parts: Popular brands have better aftermarket support and readily available replacement parts.
- Roof condition and mounting: Inspect the roof deck for delamination, cracks, or prior leaks that could complicate installation.
How To Assess Condition And Value
A thorough assessment helps determine if a used unit is a sensible bargain. Focus on cooling performance, compressor condition, and seals. Use these steps:
- Request complete service history: Prior maintenance, refrigerant recharge, and any repairs indicate reliability.
- Inspect the housing and fins: Look for rust, corrosion, bent fins, or physical damage that could impair airflow.
- Check the seals and gaskets: Worn door seals reduce efficiency and may cause leaks around the roof opening.
- Listen for abnormal noises: A humming compressor is normal; grinding or rattling may signal motor issues.
- Assess the fan and motor: Spin the fan manually to detect binding; motors with visible wobble or excessive play are red flags.
Compatibility And Installation Basics
Proper fitment is crucial for performance and safety. The installation process for a used unit often mirrors a new install, with emphasis on mounting, ducting, and seals. Key factors include:
- Roof opening and flange: Ensure the mounting flange aligns with the roof cutout. Some units require adapters or new foam sealant for a watertight seal.
- Electrical considerations: Confirm the RV’s electrical system can handle the load, especially when paired with other appliances at idle or on the road.
- Condensation drainage: Verify proper drainage paths and ensure the condensate pan or drainage line remains unobstructed.
- Refrigerant integrity: A sealed refrigerant circuit is critical. Avoid units with visible refrigerant stains or lingering smells, which may indicate leaks.
Efficiency, Power Needs, And Running Costs
Efficiency directly affects fuel or generator usage when boondocking. Standout points include:
- Energy efficiency ratio (EER) and SEER: Higher ratings reduce power draw, increasing on-site autonomy.
- Startup surge: Some units draw a higher current briefly at startup; ensure circuits and breakers accommodate this spike.
- Airflow and ducting: Maximize airflow with clean filters and properly sealed ducts to reduce cooling time and energy use.
- Maintenance impact: Clean coils, replace filters, and inspect seals to maintain efficiency over time.
Where To Find And How To Inspect
Used RV roof air conditioners can be sourced from online marketplaces, RV salvage yards, and RV communities. When inspecting online listings, request:
- Photos of the exterior and interior: Look for rust, dents, and visible wear on the housing and fan blades.
- Serial number and model: Verify compatibility with replacement parts and service availability.
- Proof of ownership and return policy: Prefer sellers offering at least a limited return window and a tested demonstration.
On inspection day, bring basic tools and check:
- Electrical tests: If possible, test the unit on a dedicated 120V circuit to verify startup and cooling function.
- Leak check: Look for refrigerant stains, oily residues, or hissing sounds that indicate leaks.
- Mounting hardware: Ensure the unit includes or can accommodate mounting brackets and a secure sealant kit.
Maintenance And Safety Tips
Proper maintenance extends the life of a used roof air conditioner and reduces safety risks. Consider these practices:
- Regular filter replacement: Clean or replace cabin and return air filters every few months during heavy use.
- Clean coils and fins: Dust buildup reduces efficiency; use a soft brush and coil cleaner per manufacturer guidelines.
- Inspect seals and caulking: Re-seal the roof penetration to prevent leaks, especially after seasonal storage or travel in harsh weather.
- Electrical safety: Verify wiring, breakers, and grounding meet code requirements and are up to date.
- Professional servicing: Schedule periodic inspections to confirm refrigerant levels, electrical integrity, and overall performance.
Practical buying checklist
- BTU rating: Align with RV size and insulation.
- Brand and parts availability: Prefer well-supported models.
- Roof compatibility: Confirm opening size and mounting flange fit.
- Condition: Assess housing, coils, seals, and fan operation.
- Electrical readiness: Ensure voltage and amperage suit your system.
- Warranty or return policy: Favor sellers offering some protection.
For readers in the United States, understanding typical upgrade paths and compatibility nuances helps ensure the used roof air conditioner provides reliable comfort during road trips. With careful evaluation, a well-chosen used unit can deliver efficient cooling, reasonable energy use, and long-term satisfaction for RV adventures.