Description

The DIY-MULTI3-18HP230D-O — MRCOOL 18,000 BTU 23.9 SEER2 Air Conditioner Condenser – DIY-MULTI3-18HP230D-O — is stocked and shipped by Buy Comfort Direct from Winder, Georgia. Specifications, fitment notes and ordering details are below; call (877) 843-4822 if you need it matched to your equipment first.

About the DIY-MULTI3-18HP230D-O

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margin-bottom: 40px;
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border-color: #D53938;
transform: translateY(-5px);
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.warranty-years {
font-size: 48px;
font-weight: 700;
color: #D53938;
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.warranty-label {
color: #333;
font-size: 14px;
font-weight: 600;
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background: linear-gradient(135deg, #F8F9FA 0%, #e9ecef 100%);
padding: 60px 30px;
border-radius: 15px;
margin-top: 50px;
box-shadow: 0 10px 40px rgba(0,0,0,0.2);
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text-align: center;
margin-bottom: 40px;
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font-size: 28px;
font-weight: 700;
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color: #333;
margin: 0;
font-size: 16px;
max-width: 700px;
margin-left: auto;
margin-right: auto;
line-height: 1.6;
}

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.warranty-note {
margin-top: 15px;
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color: #666;
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.cta-note {
margin-top: 20px;
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background: rgba(213,57,56,0.05);
border: 2px solid #D53938;
border-radius: 12px;
padding: 25px 30px;
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gap: 20px;
max-width: 700px;
margin: 0 auto;
transition: all 0.3s ease;
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@media (max-width: 768px) {
#product-container {
padding: 15px;
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font-size: 1.8em;
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font-size: 1.4em;
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.specs-table {
font-size: 0.9em;
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padding: 10px;
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flex-direction: column;
text-align: center;
padding: 20px;
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text-align: center;
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.cta-section {
padding: 40px 20px;
}

.tab-label {
display: block;
width: 100%;
margin-right: 0;
margin-bottom: 5px;
border-radius: 8px;
}

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border-radius: 8px;
}
}

Where the DIY-MULTI3-18HP230D-O fits

This is a multi-zone outdoor condenser. One outdoor unit drives several indoor heads, which are bought separately and matched to the rooms they serve. Total outdoor capacity is 18,000 BTU, and that is what gets divided across the heads. It runs on 230V and needs a dedicated 230V circuit. At 23.9 SEER2 it sits at the efficient end of this size class. The DIY line ships with pre-charged Quick Connect line sets — no vacuum pump, no refrigerant handling, no EPA 608 certification. Installing it yourself still keeps the 7-year compressor and 5-year parts coverage.

See the rest of the range in MRCOOL mini splits, or run the numbers with our HVAC sizing tool. Not sure what pairs with what? Call (877) 843-4822 and we will check it before you buy.

DIY-MULTI3-18HP230D-O: fitment and resources

Equipment ratings are only valid as an AHRI-matched pairing; confirm the match before ordering. Our free HVAC system sizing tool gives a starting point for tonnage, and Background reading: the ENERGY STAR central air conditioner guide. Browse the rest of our DIY 5th Gen Multi-Zone or the MRCOOL catalog, and see what customers say on our reviews page.

Ordering and delivery

In-stock items ship from our Winder, Georgia warehouse; orders over $99 ship free. Large equipment travels by freight carrier and parts by ground, with tracking by email. Financing is available at checkout through Affirm, and contractors can set up a contractor account for trade pricing. Questions before you pay? Use the contact page or call (877) 843-4822.

DIY-MULTI3-18HP230D-O FAQ

Does the DIY-MULTI3-18HP230D-O ship free?

Yes on orders over $99 — most orders that include it qualify.

How do I know it fits my system?

Send us your equipment model number through the contact page or call (877) 843-4822 and we will confirm the match before it ships.