Under bench AC mount

Why choose an under bench AC mount

An under bench AC mount places the cooling hardware beneath a seat base or cabinet to free wall and ceiling real estate. It keeps the profile clean, reduces visual clutter, and can lower the center of gravity compared to roof equipment. For road travel, that matters. The bench cavity can also soften compressor noise when the intake and discharge are ducted well. Done right, you gain cool air delivery without sacrificing headroom or exterior aesthetics.

Thermal performance realities

Cooling performance starts with a realistic heat load. Vehicle glass area, insulation, sun exposure, number of occupants, and appliance waste heat all affect the required BTU capacity. Oversizing can short cycle and cause humidity issues, while undersizing runs hot and draws heavy power without reaching setpoint. A balanced capacity, correct duct sizing, and minimal recirculation create steady cabin conditions.

Airflow and static pressure

Under bench installations introduce bends and fittings that raise static pressure. To keep airflow up, use smooth radius curves, short runs, and adequately sized supply and return grilles. Starving the return is a common mistake. The return path should be at least equal to the sum of supply cross sectional area, with a straight shot into the evaporator to reduce turbulence.

Noise and vibration

Bench structures can act like a drum. Place the AC on rubber isolators, decouple ducts from wood or metal panels, and use lined duct where appropriate. Avoid grille placements that fire directly at seating positions. A low frequency hum can be reduced by adding mass to panels and by using flexible couplers between the unit and hard duct.

Design considerations and best practices

• Intake and discharge separation: Prevent short cycling by locating the return low and central, and the supply aimed across the living zone. Keep at least several feet of path separation.
• Condenser heat strategy: Self contained units with a water cooled or air cooled condenser need a plan. Water cooled models route heat to a seawater loop in marine contexts, while most van setups require exterior venting for condenser air. Without exterior venting, the system will heat the bench cavity and stall.
• Service access: Build a removable panel for filter service, electrical checks, and condensate trap maintenance. If you need to disassemble cabinetry to reach a filter, you will delay maintenance and performance will suffer.
• Condensate management: Slope the drain line continuously downward, avoid sags, and include a trap as required by the unit to prevent air bypass. Route to the exterior with a splash guard and check valve where appropriate. In freezing climates, slope and protect the line to prevent ice blockages.
• Electrical planning: Check locked rotor current or inverter start current. Size wire gauge and fuses to the manufacturer amp draw and run length. If running from batteries, account for inverter efficiency and surge. Some systems use variable speed compressors that reduce inrush and lower average draw.
• Ventilation and make up air: If the condenser is air cooled, create a sealed duct path from exterior intake to the condenser and back out through a discharge grille. Isolate this hot air stream from the living space and from the evaporator return.

Fitment in vans and towables

Bench cavities vary from compact wheel well cabinets to full length settees. Before cutting a single panel, confirm unit dimensions with service clearances, duct bend radii, and grille footprints. Map every component on a scale template to avoid last minute compromises. Keep heavy components low and well supported by structure tied into the vehicle floor. Reinforce mount points with plates to distribute loads across the subfloor and ribs.

Travel introduces shock, dust, and moisture. Choose corrosion resistant fasteners, locking hardware, and abrasion sleeves where ducts or wires pass through panels. Seal exterior penetrations with the correct sealant for the substrate. Add an accessible clean out for the drain and a way to wipe the return filter without pulling the entire seat box apart.

Winter use brings different needs. Provide a tight close off panel or damper for exterior condenser ducts to reduce cold drafts during non cooling seasons. If the unit has an optional heat mode, remember that airflow and power rules still apply. Protect the drain from freeze and test it at the start of each season.

Under bench layouts reward careful grille placement. A low return near the unit helps collect warm stratified air, while high sidewall supplies can deliver cool air across the cabin rather than dumping it at your knees. If the floor plan includes a bed platform, consider a second supply into that zone to avoid hot pockets.

For noise, aim for a solid bench with internal mass and strategic soft mounts. A thin plywood box will resonate; adding constrained layer damping and stiffeners can tame vibrations. Keep panel gaps tight so the return does not pull air that bypasses your filter.

Small choices add up. A slightly larger radius elbow, a smoother return path, a few extra inches of service clearance, and a better drain slope can be the difference between quiet, reliable cooling and an AC that struggles on a summer afternoon.

To see how a purpose built under bench layout fits within a complete adventure van, explore recreational vans. If you want a layout tailored to your travel style, look at our custom van builds. For shoppers seeking a finance friendly platform that supports clean AC integration, review our mainstream vans.

When a professional install is worth it

Space is tight, power budgets are finite, and airflow is unforgiving inside a vehicle. A professional team can model heat loads, route exterior ducts cleanly, and make service access painless, all while protecting storage space. The result feels simple because the planning was thorough.

How OZK Customs can help

We design under bench AC solutions that respect your floor plan, power system, and climate. Our team builds vans for real travel, then hands them off at our Fayetteville shop with a walkthrough so you know how everything works. You leave with quiet comfort and room for gear.

Get moving

If cooling is the missing piece, we can make the bench work for you instead of against you. Share your platform and priorities and we will map the airflow, drainage, and power to match your routes and seasons.

Ready to cool the cabin without giving up space? Tell us about your rig and goals. We will plan an under bench AC mount that runs quiet, drains reliably, and fits your build. Reach out today and we will guide the next steps.