RJ HVAC
DIY 18k 3-zone condenser — 230V

3 photos · sourced from matching MRCOOL 5th Gen product listings

MRCOOL

Shop/DIY

DIY 18k 3-zone condenser — 230V

DIY-MULTI3-18HP230D-O

Outdoor unit for 2–3 indoor heads. Factory chart: 3-zone mixes are 6k/9k only. Up to ~750 sq ft.

Power
230V
Typical space
Up to ~750 sq ft
SEER2
23.9
Refrigerant
R-454B
Max fuse / breaker
20A
MCA
16A
Warranty
7-year compressor / 5-year parts
Line set
Quick Connect per indoor head (pick rooms on Size my system)
ENERGY STARTax-credit eligible

Heat: Standard 5th Gen — not Hyper Heat

ENERGY STAR® and federal tax-credit eligible. Indoor mixes follow MRCOOL’s published 5th Gen matchup chart. Indoor sizes 6k–24k; 36k wall heads are not on that chart.

$1,555

MAP. Drop-shipped from MRCOOL. Montana has no statewide sales tax. Free shipping on orders $1,000+.

Build this system

Pick a head for each zone

This 18k outdoor takes 2–3 indoor units. Factory chart indoor sizes are 6k, 9k, 12k, 18k, and 24k · Up to ~750 sq ft. We’ll only add a mix MRCOOL publishes.

How many indoor units?

Factory-approved mixes

From MRCOOL’s 5th Gen matchup chart. Click one to load it, then change a room if you need to.

Zone 1

Line set for this head

25 ft Quick Connect · Includes matching 25-ft DIYPRO cable with this line set (in the price). 3 LineGuard kits (12 ft each) to cover this run.

Zone 2

Line set for this head

25 ft Quick Connect · Includes matching 25-ft DIYPRO cable with this line set (in the price). 3 LineGuard kits (12 ft each) to cover this run.

Quick Connect, pre-charged, with matching DIYPRO cable in the line-set price. Each head can be a different length.

Factory-approved mix from MRCOOL’s 5th Gen chart. 21k connected on a 18k outdoor — if every head runs at once, output will not exceed the outdoor rating.If every indoor unit runs at once, combined BTU output will not exceed the outdoor rating. That’s how MRCOOL publishes the matchup chart.
  • DIY 18k 3-zone condenser — 230VDIY-MULTI3-18HP230D-O$1,555
  • DIY 9k indoor head — 230VDIY-09-HP-WMAH-230D25-O$532
  • DIY 12k indoor head — 230VDIY-12-HP-WMAH-230D25-O$689
  • 25-ft line set 1/4×3/8 + DIYPRO — 6k/9k/12kDIY25-1438C-O$314
  • 25-ft line set 1/4×3/8 + DIYPRO — 6k/9k/12kDIY25-1438C-O$314
  • 30A fused disconnectMCDP30$42
  • Condenser padMCPAD$64
  • LineGuard® 12-ft cover kit — white × 6MLG450$534

$4,044

Equipment only · free shipping · labor extra if a contractor installs it

Have us install it

Replacement outdoor only? · Pad

ENERGY STAR® and federal tax-credit eligible. Indoor mixes follow MRCOOL’s published 5th Gen matchup chart.

Brochures and manuals

Factory PDFs from MRCOOL. Open in a new tab.

More manuals (5)

What’s included

  • 18k 3-zone outdoor condenser (Gold Fin® coil)

Not included

  • Indoor heads (order separately — use the builder on this page)
  • Quick Connect line set (one per indoor head)
  • Electrical disconnect, pad, LineGuard, or labor

Other sizes

Call Now