MRCOOL DIY Coupler for 9K, 12K or 18K Air Handlers with 75 Ft. MC-5 Cable

MRCOOL DIY Coupler for 9K, 12K, or 18K Air Handlers with 75 Ft. MC-5 Cable

The MRCOOL DIY Couplers & Control Wire Kit for 9K, 12K, and 18K mini-split systems is a complete extension solution designed to help connect and extend pre-charged Quick Connect® line sets for compatible MRCOOL DIY air handlers. It provides the fittings and communication wiring needed to join refrigerant lines while maintaining a sealed refrigerant environment, allowing you to extend the distance between your indoor and outdoor units without losing refrigerant integrity.

This kit includes dual couplers sized for both liquid and suction lines, enabling secure, leak-free connections when joining or extending multiple pre-charged line sets. The design supports DIY-friendly Quick Connect technology, so no additional vacuuming or refrigerant charging is required during installation, simplifying system expansions or custom layouts.

Also included is a 75-foot MC-5 communication cable, offering long-range communication capability between the indoor air handler and outdoor unit. This extended wiring provides greater placement flexibility, ideal for installations where standard cable lengths are not sufficient.

Perfect for homeowners and installers working with MRCOOL DIY systems using 9K, 12K, or 18K BTU air handlers, this kit improves connection flexibility and ensures reliable system performance even when units must be installed farther apart.

Features

• System Compatibility – Built for MRCOOL DIY 4th Gen systems with 9K, 12K, or 18K BTU air handlers, offering reliable integration.
• Dual Coupler Sizes – Includes 1/4” and 1/2” couplers for secure, leak-free line set extensions.
• Long-Range Communication – Comes with 75 feet of MC-5 cable, allowing for extended distance between your indoor and outdoor units.
• DIY-Friendly Connection – Designed to work with MRCOOL’s Quick Connect® fittings, ensuring a simple, no-vacuum install.
• Refrigerant Protection – Maintains the sealed environment of your pre-charged line set, preventing refrigerant loss during the extension process.

Specifications

Applications

• Room-to-room installations – Enables greater placement flexibility between air handlers and condensers

• Detached structures – Ideal for garages, workshops, or sheds where added line length is needed

• Retrofits – Useful in remodeling or upgrade scenarios where existing line set paths are too short

• Large property layouts – Supports larger homes or extended zones with more complex configurations

• Multi-zone setups – Expands coverage options when multiple air handlers are used across the property

What’s Included

• DIYCOUPLER-14 (1/4” Coupler)

• DIYCOUPLER-12 (1/2” Coupler)

• 75 Ft. MC-5 Communication Cable
  

Frequently-Asked Questions

Is this compatible with all MRCOOL systems?
No. This coupler kit is specifically designed for MRCOOL DIY 4th Gen systems using 9K, 12K, or 18K BTU air handlers. It is not suitable for larger units or non-DIY models.

Do I need to vacuum or charge the lines?
No. The couplers are designed for use with prefilled Quick Connect® line sets, maintaining a sealed system—no vacuuming or refrigerant charging is needed.

Can I install this myself?
Yes, if you’re comfortable with MRCOOL DIY installations. For complex layouts or if you’re uncertain, it’s always best to consult or hire a certified HVAC professional.

Manual

• Installation Manual