Choose
Single-zone vs multi-zone mini splits
How single-zone and multi-zone ductless systems differ: rooms covered, indoor unit options, line-set routing, and how each one is selected.
Decision guide
Guides · 8 planning guides
Plan your system with clear guidance
Sizing, electrical, line sets, and which parts of the job are yours.
Choose
Mini-split sizing guide
What size mini split you need by room area, why a bigger unit is not a better fit, and when a Manual J calculation is the deciding step.
2 min read
Prepare
Mini-split voltage: 115V and 230V
How to tell whether a DIY mini split runs on 115V or 208/230V, what each one means for your panel, and what to hand an electrician.
2 min read
Prepare
Mini-split line set length and routing
How long the included line set is, why measuring the real route matters before you order, and what a pre-charged Quick Connect line set changes.
2 min read
Install
DIY versus professional installation
What the pre-charged Quick Connect line set removes from a mini-split installation, which parts a homeowner can do, and which still need a licensed trade.
2 min read
Install
Mini-split installation planning
How to choose indoor and outdoor unit locations, plan the line-set route and the condensate drain, and know what to measure before you order.
3 min read
Install
R-454B refrigerant in DIY 5th Gen mini splits
What refrigerant DIY 5th Gen mini splits use, what a pre-charged line set means for installation, and which work still belongs with qualified people.
2 min read
Support
MRCOOL DIY warranty terms
The base warranty MRCOOL publishes for DIY 5th Gen systems, what the document actually governs, and how to keep a claim-ready record.
2 min read