Parking air conditioner storage procedure — long-term off-season best practices

• Table of Contents

1. Pre-storage shutdown sequence
2. Physical protection — covers, vents and rodent ingress
3. Battery, contactor and refrigerant preservation
4. Pre-return-to-service inspection

RV owners parking for 6+ months and fleet operators retiring trucks for the off-season need a formal storage procedure that protects refrigerant charge, battery health, gasket integrity and control electronics. This procedure prevents the most common storage damage modes: condensate freeze, gasket compression set, battery sulphation, contactor corrosion and rodent ingress.

Pre-storage shutdown sequence

Run fan-only mode for 30 minutes to dry the evaporator. Pump down the refrigerant circuit if the manufacturer permits (Vethy units do not require pump-down). Clean both coils. Isolate the battery bank. Document the date and operating hours in the fleet log.

Physical protection — covers, vents and rodent ingress

Fit the OEM winter cover or a UV-stable tarpaulin. Block intake/exhaust openings with breathable mesh to prevent rodent and insect ingress without trapping moisture. Inspect the rooftop annually for cover degradation, especially in high-UV climates.

Battery, contactor and refrigerant preservation

Store LiFePO4 banks at 40–60% state of charge in a heated space if possible. AGM/lead-acid banks need monthly maintenance charge or a permanent maintainer. Spray dielectric grease on contactor terminals. Refrigerant charge holds for the entire storage period if the system is properly sealed.

Pre-return-to-service inspection

Before re-commissioning after storage, perform the full summer pre-season checklist: visual inspection, coil cleaning, refrigerant pressure check, battery load test, control function test and full load test. Storage damage typically reveals itself in pressure-test or load-test results.

Frequently asked questions

Can I store the vehicle outdoors over winter with parking AC?

Yes. Vethy units are rated for outdoor storage from -40°C to +70°C ambient. Fit a winter cover and isolate the battery bank for best results.

Do I need to recharge refrigerant after long-term storage?

No. A correctly sealed refrigerant circuit holds charge for years of storage. If you measure low pressure on return-to-service, locate and repair the leak before recharging.

How often should I check the unit during long storage?

Quarterly visual inspection of cover integrity, mounting bolts and rodent ingress. Monthly battery maintenance charge if not using a permanent maintainer.