Central Pneumatic 21 User Manual

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21
GAL
cast iron
vertical air
compressor
Owner’s Manual & Safety Instructions
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2013 by Harbor Freight Tools
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. All rights reserved.
No portion of this manual or any artwork contained herein may be reproduced in
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Diagrams within this manual may not be drawn proportionally. Due to continuing
improvements, actual product may differ slightly from the product described herein.
Tools required for assembly and service may not be included.
Read this material before using this product.
Failure to do so can result in serious injury.
SAVE THIS MANUAL.
REV 15a

Central Pneumatic 21 Specifications

General

Maximum Pressure	125 PSI
Voltage	120V
Tank Size	21 gallons
Amps	15 A
Noise Level	78 dB

Summary

Important Safety Information

General Safety Guidelines

Covers work area, electrical, personal safety, and compressor use/care.

Air Compressor Safety Warnings

Operational Hazards

Warnings related to fire, bursting, injury, and ventilation during operation.

Maintenance and Handling Safety

Grounding

Grounding Warning

Essential precautions to prevent shock from incorrect grounding.

110-120 VAC Grounded Compressors

Specifications

Assembly

Break-in Procedure

Connecting Air Lines

Checking the Oil

Operating Instructions

Compressor Area Set Up

Instructions for preparing the workspace for compressor operation.

General Operation

Explosion Hazard Warning

Critical warning against adjusting the internal pressure switch.

Pressure Regulator Adjustment

Connecting Air Tools

Post-Operation Procedures

Maintenance and Servicing

Pre-Operation Inspection

Maintenance Schedule

Recommended frequency for various maintenance tasks.

Oil Maintenance

Draining Moisture from the Tank

Daily procedure to remove trapped air and moisture from the tank.

Air Filter Maintenance

Troubleshooting

Compressor Does Not Start or Restart

Solutions for issues preventing the compressor from starting.

Compressor Builds Pressure Too Slowly

Troubleshooting steps for slow pressure buildup.

Compressor Not Building Enough Air Pressure

Diagnosing and fixing issues with insufficient air pressure.

Troubleshooting (cont.)

Overheating

Reasons for compressor overheating and how to resolve them.

Compressor Starts and Stops Excessively

Solutions for frequent starting and stopping cycles.

Excessive Noise

Discharge Air Quality Issues

Parts List and Diagram

Parts List

Assembly Diagram