The Professional Finish: Installing Your AVC Espar Heater Trim Unit

Hey everybody, Matt here for AVC and welcome back to the blog! Today we're installing the AVC Espar heater trim unit on the Ford Transit passenger seat base.

We've been working closely with Espar to ensure their D2L/S2D2L furnaces are properly integrated into the Ford Transit platform. To further this integration, we developed this custom AVC Espar Heater Trim Unit. This unit ensures proper duct alignment, a superior fit with the Ford Transit seat base, and a professional, finished appearance.

Whether you're a DIY-er or a professional installer, this trim unit is designed to give your heater better performance and a clean look.

Key Features of the Espar Heater Trim Unit

The unit is designed to utilize existing factory features for a flawless installation:

• Factory Alignment: The three holes on top align perfectly with the factory mounting holes on your Transit seat base.

• Duct Alignment: The mounting point for the ducting register aligns precisely with a correctly placed Espar furnace.

• Customizable Plug: The small tree logo on the bottom right can be twisted out and replaced with a 12V or USB charging plug.

Now, let’s get to work!

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Step 1: Remove the Seat and Inverter

To gain clear access to the seat base, you need to remove the passenger seat and the factory inverter.

1. Remove Seat: Use a 10mm socket to remove the four bolts securing the seat to the base. Use a 7mm socket to disconnect the wiring harnesses underneath the seat. Optional: Remove the seat belt attachment (T50 Torx) to completely clear the work area.

2. Remove Inverter: The Ford Transit often comes with a 400-watt square wave inverter inside the seat base. We recommend removing this.

   • Use a deep well 10mm socket to remove the three bolts securing it.

   • Disconnect the wiring and set the unit aside.

3. Remove Seat Base: Use a 15mm socket and a long extension to remove the four main bolts securing the seat base to the floor of the van.

4. Disconnect Wiring: Use a panel popper tool and your fingers to pop off any remaining wiring harness connections secured to the base.

Step 2: Modify the Seat Base

The stock seat base has several components that must be removed or cut to allow the furnace and ducting to pass through.

1. Cut the Hoop: Use an angle grinder to cut off the large metal hoop at the very top of the seat base.

2. Mark the Ducting Area: Dry-fit the seat base back into the van and place the AVC trim unit over the mounting holes. Use a marker to trace the area where the ducting will exit, ensuring you flare the lines out slightly to give the duct plenty of room.

3. Mark the Heater Placement: Use the AVC template to mark the consistent placement of the Espar unit on the van floor, centered over the factory bolts.

4. Cut the Floor Bolts: Use a vibrating saw (multi-tool) to cut the two bolts securing the old inverter flat to the floor. Avoid cutoff discs or flap wheels inside the van to minimize sparks and potential rust.

Step 3: Cut the Base for Ducting Access

With the seat base back on the bench, use your markings to cut the necessary openings.

1. Define the Cut: Connect your marks to form a large, diagonally-shaped opening at the back of the seat base. This provides room for the ducting and tool access.

2. Critical Integrity: DO NOT cut into the following areas:

   • Any factory welds securing the seat base together.

   • The rolled (bent) metal edge around the bottom, as this provides crucial structure and strength.

3. Cut and Prep: Use an angle grinder to cut out the marked section. Paint all raw metal edges immediately to prevent rust.

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Step 4: Assemble the Trim Unit

The final installation steps are done outside the van for easy access.

1. Install the Register: Place the Espar ducting register onto the back of the AVC trim unit, aligning the three pilot holes. Secure it using three self-tapping screws (a wood screw will also work in the aluminum).

2. Attach Ducting: Install the 60mm heater ducting onto the register and secure it tightly with the provided clamp.

3. Install the Grille: Snap the grille onto the front. We recommend orienting the grille to blow the hot air upwards rather than forcing it down onto the floor.

⚡️ Optional: Add a Charging Port

To install a charging plug in place of the logo:

1. Remove Logo: Take the trim unit and twist the small tree logo back and forth until the connecting aluminum tabs fatigue and break, allowing the logo to pop out.

2. Install Plug: Slide your 12V or USB outlet into the opening and secure it with its locking nut on the back.

Step 5: Final Installation

1. Attach Trim to Base: Place the AVC trim unit onto the modified seat base. Use the included stainless hardware: thread the large washer and stainless Allen bolts through the top, and secure them underneath with the small washer and a 5mm Nylock nut.

2. Reinstall Heater: At this stage, you would typically install your Espar unit (a separate process) on the floor over your template marks.

3. Reinstall Seat Base: Bolt the modified seat base, with the attached trim unit, back into the van floor.

4. Reinstall Seat: Reconnect the wiring and bolt the passenger seat back onto the base.

The AVC Espar heater trim unit integrates perfectly with the floor system and provides a clean, professional finish for your Espar heater installation.

Shop the Ford Transit seat base heater trim, browse more Ford Transit van accessories, and watch the full install on our YouTube channel.