Mastercool 82834 — R134a High-Side Manual Service Coupler

Professional manual service coupler for R134a high-side (discharge) connections. Features 1/4" FL-M manifold connection and 16mm service port fitting for secure, leak-free attachment to R134a automotive and HVAC systems. Manual thumb-operated valve provides precise control over refrigerant flow. Durable brass construction ensures long service life in demanding professional environments.

Key Features

• R134a High-Side: 16mm service port for discharge connections
• Manual Operation: Thumb-operated valve for precise control
• 1/4" FL-M Connection: Standard flare male fitting for manifold hoses
• 16mm Service Port: High-side (red) connection for R134a systems
• Brass Construction: Durable, corrosion-resistant materials
• Leak-Free Design: Precision-machined for reliable sealing
• Professional Quality: Built for daily workshop use
• Universal Compatibility: Works with all R134a systems

Technical Specifications

• Model: 82834
• Type: Manual service coupler
• Side: High-side (discharge/red)
• Refrigerant: R134a
• Manifold Connection: 1/4" FL-M (flare male)
• Service Port: 16mm (high-side)
• Operation: Manual thumb valve
• Material: Brass
• Barcode: 700376117417
• SKU: 82834
• HS Code: 84189910

Related Coupler Models

Low-Side Coupler:

• 82934-E — R134a Low-Side Manual Coupler 1/4" x 13mm

Alternative Connections:

• 82834-3/8 — High-Side Manual Coupler with 3/8" Fitting
• 82834-EU — High-Side Manual Coupler with 14mm-F Connection
• 82834-J — High-Side Manual Coupler M12 x 1.75 (Japanese/Asian)
• 82834-SL-E — High-Side Manual Coupler with Safety Lock

Applications

• R134a automotive A/C service
• R134a HVAC system service
• High-side (discharge) connections
• Manifold gauge set connections
• Refrigerant charging and recovery
• System diagnostics and pressure testing
• Professional automotive and HVAC service

Why Manual Couplers?

Manual service couplers feature a thumb-operated valve that provides precise control over refrigerant flow:

• Controlled Connection: Open valve gradually to prevent pressure surges
• Reduced Refrigerant Loss: Close valve before disconnecting to minimise venting
• Safety: Control refrigerant release during connection/disconnection
• Professional Standard: Preferred by many technicians for controlled operation
• Reliable: Simple mechanical design with fewer failure points

High-Side vs Low-Side

• High-Side (82834 - This Coupler): 16mm service port, red, connects to discharge/high-pressure side
• Low-Side (82934-E): 13mm service port, blue, connects to suction/low-pressure side

R134a Service Port Sizes

R134a systems use different service port sizes to prevent incorrect connections:

• High-Side: 16mm (larger) - prevents low-side hose connection
• Low-Side: 13mm (smaller) - prevents high-side hose connection

This safety feature ensures technicians cannot accidentally connect hoses to the wrong side of the system.

Benefits

• Manual Control: Thumb valve provides precise refrigerant flow control
• Reduced Venting: Close valve before disconnecting to minimise refrigerant loss
• Universal R134a: Works with all R134a automotive and HVAC systems
• Durable Brass: Corrosion-resistant construction for long service life
• Leak-Free: Precision-machined for reliable sealing
• Professional Quality: Built for daily workshop use
• Standard Connection: 1/4" FL-M fits all standard manifold hoses
• Safety Design: 16mm port prevents incorrect low-side connection

How to Use

1. Ensure high-side service port (16mm, red cap) is clean
2. Remove service port cap
3. Ensure coupler thumb valve is closed
4. Push coupler onto 16mm high-side service port
5. Verify secure connection
6. Slowly open thumb valve to allow refrigerant flow
7. Perform service operation
8. Close thumb valve before disconnecting
9. Remove coupler from service port
10. Replace service port cap

Perfect For

• Automotive A/C technicians
• HVAC service technicians
• R134a system service
• Workshop environments
• Mobile service operations
• Fleet maintenance
• Professional refrigerant service

Manual vs Quick Connect Couplers

Manual (82834 - This Coupler):

• Thumb-operated valve for precise control
• Reduced refrigerant loss during disconnection
• Simple, reliable mechanical design
• Preferred by many professional technicians
• Lower cost

Quick Connect:

• Faster connection/disconnection
• One-handed operation
• No valve to operate
• Higher cost

Maintenance

• Keep coupler clean and free from debris
• Inspect O-rings regularly for wear
• Replace O-rings if leaks develop
• Lubricate O-rings occasionally with refrigerant oil
• Check thumb valve operation - should move smoothly
• Store in protective case when not in use

Safety Notes

• Always wear safety glasses when connecting/disconnecting
• Ensure system pressure is safe before connecting
• Close thumb valve before disconnecting to minimise refrigerant loss
• Never force coupler onto service port
• Verify correct port size (16mm high-side)
• Follow proper refrigerant handling procedures

Professional Quality: Mastercool manual service couplers are built to professional standards for reliable, controlled refrigerant connections in demanding automotive and HVAC service environments. Essential accessory for R134a system service.