Installation Guide
Tools Needed:
- Adjustable wrench set
- Level
- Screwdrivers (flat and Phillips)
- Pipe wrench
- Tape measure
- Voltage tester
Step-by-Step Installation
- Choose Installation Location: Select a clean, dry, well-ventilated location with adequate space for maintenance access and proper air circulation.
- Foundation Preparation: Place compressor on a solid, level concrete foundation capable of supporting the unit's weight during operation.
- Electrical Connection: Connect to appropriate power supply (see specifications). All electrical connections must comply with local codes and be performed by a qualified electrician.
- Air System Connection: Install proper air lines with minimum restriction. Include shut-off valves, drains, and pressure regulators as needed.
- Oil Check: Verify proper oil level in crankcase before initial startup (use Quincy recommended compressor oil).
- Pressure Settings: Set cut-in and cut-out pressures according to application requirements and manufacturer specifications.
- Initial Run Test: Run compressor through complete cycle to check for proper operation, leaks, and unusual noises.
Specifications
| Model Series | QT-390 |
| Type | Two-Stage Reciprocating Air Compressor |
| Compression Stages | 2 |
| Horsepower | 15 HP |
| Maximum Pressure | 175 PSI |
| Air Delivery (CFM) | 54.5 CFM at 175 PSI |
| Tank Capacity | 120 Gallon ASME |
| Noise Level | 78 dB(A) at 1 meter |
| Control Type | Pressure Switch with Magnetic Starter |
| Power Requirements | 230V/460V, 3 Phase, 60Hz |
| Dimensions (LxWxH) | 72 x 36 x 68 inches |
| Weight | 980 lbs |
| Oil Capacity | 3.5 Quarts |
Warranty Information
- Full Warranty: 2 years parts and labor
- Pump Warranty: 5 years on Quincy QT pump
- Tank Warranty: Lifetime on ASME tank
- Additional Coverage: Optional extended warranty available
For warranty service, contact Quincy Compressor Customer Service at 1-800-331-1955 or visit QuincyCompressor.com
Key Features
QT Pump Technology
Quincy's patented QT pump features large diameter crankshaft, pressure-lubricated design, and efficient intercooling between stages for maximum durability and performance.
Two-Stage Compression
Dual compression stages provide cooler operation, higher efficiency, and longer component life compared to single-stage compressors.
Pressure Lubrication System
Full pressure lubrication ensures all moving parts receive proper oiling, reducing wear and extending service intervals.
ASME Certified Tank
Heavy-duty 120-gallon ASME certified air receiver tank with lifetime warranty provides ample air storage for demanding applications.
Thermal By-Pass Valve
Automatic thermal protection prevents overheating during startup and ensures proper oil flow in cold conditions.
Heavy-Duty Construction
Industrial-grade components, cast iron construction, and oversized bearings provide reliable operation in demanding environments.
Operating Features Explained
Magnetic Starter
Provides overload protection and allows for remote control operation with low-voltage controls
Intercooler System
Cools air between compression stages, improving efficiency and reducing moisture in the air system
Automatic Tank Drain
Electronically controlled drain valve automatically removes condensate from tank
Pressure Gauge Set
Dual gauges display tank pressure and system pressure for precise monitoring
Safety Valve
ASME certified safety relief valve provides protection against over-pressurization
Vibration Isolators
Rubber isolators minimize vibration transmission to floor and surrounding structures
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Compressor won't start | Power issue, pressure switch fault, thermal overload tripped | Check power supply, reset overload, verify pressure switch settings |
| Excessive noise/vibration | Loose components, worn bearings, improper foundation | Tighten all fasteners, check bearings, verify level installation |
| Low pressure output | Worn valves, intake filter clogged, air leaks | Check/replace valves, clean air filter, inspect for leaks |
| Overheating | Dirty cooling fins, low oil, restricted ventilation | Clean cooling surfaces, check oil level, ensure proper airflow |
| Excessive oil consumption | Worn rings, leaking seals, overfilling | Check compression, inspect seals, verify proper oil level |
| Frequent cycling | Air leaks, worn check valve, improper pressure settings | Locate/fix leaks, replace check valve, adjust pressure switch |
Maintenance Codes & Indicators
- Red Oil Light: Low oil pressure - Stop compressor immediately and check oil level/pump
- Yellow Service Light: Maintenance required - Check service intervals and perform required maintenance
- Thermal Overload Trip: Motor overheating - Allow cool down, check ventilation and load conditions
- High Temperature Shutdown: System overheating - Check cooling system, clean surfaces, verify oil flow
- Pressure Switch Failure: Control malfunction - Check/replace pressure switch, verify electrical connections
- Unloader Valve Issue: Startup problems - Check unloader valve operation and air lines
Manual Downloads
QT Series Manuals
QT-390
15HP Two-Stage Compressor
QT-375
10HP Two-Stage Compressor
QT-425
20HP Two-Stage Compressor
QT-540
25HP Two-Stage Compressor
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Dryers & Filters Manual
Parts Catalog
QT Series Parts Manual