MRCOOL logo20,000 BTU heat pump

MRCOOL DIY 20,000 BTU Ceiling Cassette

Model #: DIYHH-18-HP-C-230D25-O / DIYCASSETTE18HP-230D25-O

Every spec on this page comes from an official certification record or a cited manufacturer document. The source is linked next to each value.

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Check model number DIYHH-18-HP-C-230D25-O / DIYCASSETTE18HP-230D25-O at your preferred retailer.

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MRCOOL DIYHH-18-HP-C-230D25-O outdoor mini-split unit

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Community sentiment

What owners report

These are recurring themes in linked public owner discussions, not certified specifications or our reliability verdict.

Several owners on Hearth.com and The Garage Journal report completing MRCOOL DIY installations themselves.

Theme: Owner installation experience

Several · 4 first-person owner reports across 2 public discussions

A small sample can reveal themes, not failure rates. Thin or single-source themes are omitted rather than filled in.

Decision guide

At a glance

What the published numbers mean before you compare every spec.

Cold-weather output

At 5°F, certified output is 17,500 BTU/h — 88% of its 47°F rating.

ENERGY STAR ↗

DIY status not confirmed

The cited fields do not confirm a pre-charged line set or DIY-line designation for this model.

Electrical service

208/230V equipment; confirm the dedicated circuit and disconnect requirements with an electrician.

Manufacturer spec ↗

Heating efficiency in its size class

HSPF2 12.2 is above the 10.6 average among 38 models in the same rounded capacity class.

ENERGY STAR ↗

Good fit if…

Your room is near 1000–1200 sq. ft. under the ENERGY STAR starting-point assumptions, and a load calculation agrees.

Think twice if…

Your electrical plan does not yet account for 208/230V equipment, or your room falls outside the sizing range above.

Room guidance is a screening estimate for standard conditions. Check your room inputs; use Manual J for final sizing.

Certified spec table

Outdoor model numberDIYHH-18-HP-C-230D25-OSource: ENERGY STAR Mini-Split Heat Pumps dataset ·
Indoor model numberDIYCASSETTE18HP-230D25-OSource: ENERGY STAR Mini-Split Heat Pumps dataset ·
AHRI reference number216032552Source: ENERGY STAR Mini-Split Heat Pumps dataset ·
SeriesDIYSource: ENERGY STAR Mini-Split Heat Pumps dataset ·
Heating capacity at 47F20,000 BTU/hSource: ENERGY STAR Mini-Split Heat Pumps dataset ·
Heating capacity at 17F18,800 BTU/hSource: ENERGY STAR Mini-Split Heat Pumps dataset ·
Heating capacity at 5F17,500 BTU/hSource: ENERGY STAR Mini-Split Heat Pumps dataset ·
SEER219.8Source: ENERGY STAR Mini-Split Heat Pumps dataset ·
EER212.5Source: ENERGY STAR Mini-Split Heat Pumps dataset ·
HSPF212.2Source: ENERGY STAR Mini-Split Heat Pumps dataset ·
Voltage208/230VSource: Manufacturer spec ↗ ·
Minimum circuit ampacity19 ASource: Manufacturer spec ↗ ·
Maximum breaker / fuse25 ASource: Manufacturer spec ↗ ·

Values marked ENERGY STAR come from the certification dataset; values marked Manufacturer spec come from the linked product documents.

Specs not published for this model

The sources we cite do not publish these values for this model, so we leave them blank rather than guess.

Line set length rangePre-charged line setBrand DIY line

Check the fit for your room

Room-size guidance is a starting point, not a load calculation. Confirm sizing and installation requirements with a qualified contractor.

Check your room size

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