Hoffman HFAS100
Hoffman AS100 Hole Seal User Manual
Model: HFAS100
1. Introduction
This user manual provides essential information for the proper installation, use, and maintenance of the Hoffman AS100 Hole Seal. Designed for 1-inch conduit openings, this steel hole seal ensures protection and a secure closure for electrical enclosures and panels. Please read this manual thoroughly before installation to ensure safe and effective use.
2. Safety Information
Always observe the following safety precautions:
- Ensure power is disconnected before working on electrical enclosures.
- Wear appropriate personal protective equipment (PPE), such as gloves and eye protection.
- Handle the product carefully to avoid injury from sharp edges or components.
- Do not modify the product. Use it only for its intended purpose.
- Keep out of reach of children.
3. Product Overview
The Hoffman AS100 Hole Seal is a durable component designed to seal unused conduit openings in electrical enclosures. It provides a secure and protective barrier against dust, dirt, and moisture.
3.1 Key Features
- Steel Construction: Made from 16 gauge galvanized steel for robust performance.
- Secure Fastening: Includes a plated stud (10-32x5/8) and a wing nut for easy and secure installation.
- Effective Sealing: Designed to provide a tight seal for 1-inch conduit holes.
- Corrosion Resistance: Gray finish for enhanced durability.
3.2 Components
The Hoffman AS100 Hole Seal consists of the following main components:
- Front Plate (Gray Steel)
- Rubber Gasket/Seal
- Back Plate (Galvanized Steel)
- Plated Stud (10-32x5/8)
- Wing Nut

Figure 1: Front view of the Hoffman AS100 Hole Seal, showing its gray steel plate and black sealing gasket.

Figure 2: Rear view of the Hoffman AS100 Hole Seal, illustrating the galvanized steel back plate, threaded stud, and wing nut for securing the seal.

Figure 3: The Hoffman AS100 Hole Seal shown in hand, providing a visual reference for its compact size and thickness, approximately 2.0 inches (5 cm) in diameter.
4. Setup and Installation
The Hoffman AS100 Hole Seal is designed for straightforward installation into standard 1-inch conduit openings. Follow these steps for proper installation:
- Prepare the Opening: Ensure the 1-inch conduit opening in the electrical enclosure or panel is clean, dry, and free of burrs or sharp edges.
- Position the Front Plate: Place the gray front plate of the hole seal, with its integrated gasket, against the exterior side of the opening. Ensure the threaded stud passes through the hole.
- Attach the Back Plate: From the interior side of the enclosure, slide the galvanized steel back plate onto the threaded stud.
- Secure with Wing Nut: Thread the wing nut onto the stud and tighten it firmly by hand. Ensure the seal is compressed evenly to create a watertight and dust-tight barrier. Do not overtighten, as this may damage the gasket.
- Verify Seal: Visually inspect the seal around the perimeter to confirm it is properly seated and provides full coverage of the opening.
Once installed, the hole seal provides a permanent closure for the conduit opening.
5. Maintenance
The Hoffman AS100 Hole Seal requires minimal maintenance. Regular inspection is recommended to ensure its continued effectiveness.
- Periodic Inspection: Annually or as needed, inspect the seal for any signs of wear, cracking, or degradation of the gasket material.
- Cleaning: If necessary, clean the exterior surface of the hole seal with a damp cloth. Avoid abrasive cleaners or solvents that could damage the finish or gasket.
- Tightness Check: Periodically check the tightness of the wing nut to ensure the seal remains secure. Retighten by hand if any looseness is detected.
If the seal or any component appears damaged, it is recommended to replace the entire unit to maintain the integrity of the enclosure.
6. Troubleshooting
Most issues related to the Hoffman AS100 Hole Seal can be resolved by ensuring proper installation.
| Problem | Possible Cause | Solution |
|---|---|---|
| Seal is not tight or appears loose. | Wing nut is not sufficiently tightened. | Hand-tighten the wing nut until the seal is compressed firmly. |
| Water or dust ingress around the seal. | Gasket is damaged or improperly seated. | Inspect the gasket for damage. Ensure the seal is centered and fully covers the opening. Replace if damaged. |
| Difficulty installing the seal. | Opening size is incorrect or has burrs. | Verify the opening is a standard 1-inch conduit size. Remove any burrs or obstructions from the hole. |
7. Specifications
| Attribute | Value |
|---|---|
| Model Number | HFAS100 |
| Conduit Size | 1 inch |
| Material (Front Plate) | 16 gauge Steel |
| Material (Back Plate) | 16 gauge Galvanized Steel |
| Finish | Gray |
| Stud Size | 10-32x5/8 |
| Approximate Diameter | 1.88 inches |
| Product Dimensions | 5.1 x 5.4 x 5.3 inches (packaging) |
| Weight | 0.32 ounces |
| Manufacturer | Hoffman |
8. Warranty and Support
For information regarding warranty coverage or technical support for your Hoffman AS100 Hole Seal, please contact Hoffman customer service directly. Refer to the official Hoffman website or product packaging for the most current contact details.
Hoffman Official Website: www.hoffman.com
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