AHRI-certified numbers · Amazon prices on 2026-10-17

MRCOOL DIY vs Senville Mini-Split: 12,000 BTU, Compared

Installing it yourself? Buy the MRCOOL DIY Select. It is the only one of the two sold as DIY. Hiring a pro anyway? Buy the Senville LETO. It rates higher on cooling and on heat at 5°F, and it costs $749.01 less. That gap is your install budget.

  1. Install it yourself

    MRCOOL DIY Select 12,000 BTU 115V

    $1,549.00 · 17.5 SEER2 · 9 HSPF2 · not cold-climate · $129.08 per 1,000 BTU · sold by Spreetail

    Check price on Amazon

  2. Better numbers for less; pro install

    Senville LETO 12,000 BTU 110V

    $799.99 · 21.2 SEER2 · 8.7 HSPF2 · not cold-climate · $66.67 per 1,000 BTU · sold by Senville

    Check price on Amazon

Prices are the Amazon buy-box price on 2026-10-17 and change often. Affiliate links; we earn a commission at no cost to you.

The numbers, as of 2026-10-17: MRCOOL DIY Select 12,000 BTU (115 V) = 17.5 SEER2, 9 HSPF2, not cold-climate, not on the ENERGY STAR list, $1,549.00 on Amazon ($129.08 per 1,000 BTU), DIY install. Senville LETO 12,000 BTU (110 V) = 21.2 SEER2, 8.7 HSPF2, not cold-climate, not on the ENERGY STAR list, $799.99 ($66.67 per 1,000 BTU), professional install required. Numbers from the AHRI Directory; prices on 2026-10-17.

By Erin Rose · Updated

01 / Side by side

The two units, number by number

Both are 12,000 BTU single-room wall units that run on a standard household circuit. MRCOOL's listing says 115 V and Senville's says 110 V. The shaded cell is the better number.

Side-by-side numbers
MeasureMRCOOLSenvilleSource
Size (certified cooling) 12,000 BTU 12,000 BTU AHRI [1]
Voltage, per the listing 115 V 110 V listing spec table [3]
SEER2 (cooling efficiency) 17.5 21.2 AHRI [1]
EER2 (efficiency on a hot day) 8.5 10.1 AHRI [1]
HSPF2 (heating efficiency) 9 8.7 AHRI [1]
Heat output at 5°F 6,200 BTU 6,600 BTU AHRI [1]
Efficiency at 5°F (COP) 1.75 1.85 AHRI [1]
Cold-climate rated no no AHRI [1]
ENERGY STAR no (not on the list) no (not on the list) ENERGY STAR [2]
Refrigerant, per the listing R-454B (bullet points) R-454B (spec table) Amazon listing [3]
Refrigerant, per the certificate R-454B R-454B AHRI [1]
Install, per the listing DIY: pre-charged 11.5 ft quick-connect lines professional install required; 16 ft line set Amazon listing [3]
Warranty, per the listing "2-year warranty" (MRCOOL's own terms: 1 yr parts, 2 yr compressor) 5 yr compressor; parts 5 yr (bullets) or 2 yr (spec table); no labor Amazon listing [3]
Amazon price on 2026-10-17 $1,549.00 $799.99 Amazon buy box [3]
Price per 1,000 BTU $129.08 $66.67 computed [3]
Heating cost per million BTU $20.92 $21.64 computed, $0.1883/kWh [6]
Cooling cost per million BTU $10.76 $8.88 computed, $0.1883/kWh [6]
Sold by Spreetail Senville Amazon listing [3]
Certified model pair DIYS-12-HP-C-115A11-O + DIYS-12-HP-WMAH-115A13 - O SENL-12CD-OL + SENL-12CD-ILL AHRI refs 218004485, 215735287 [1]

Certified numbers are the AHRI ratings for the exact outdoor and indoor model pair each listing prints. ENERGY STAR is the program's own certified list on 2026-10-01. Running costs use $0.1883/kWh, the EIA U.S. average; your rate moves them.

02 / What the numbers mean for you

What the gap is worth

  • You pay for the install method. The MRCOOL costs $749.01 more. Its listing says its 11.5 ft pre-charged Quick Connect line set means "no vacuum pump, gauges, brazing, or refrigerant handling are required." The Senville listing says "Professional installation required" and "Labor not included." Get an install quote before you compare the two prices.
  • No Senville listing we read says DIY. Of the 13 Senville system listings we read on Amazon on 2026-09-29, 11 say a professional must install the unit and none call it DIY. 13 of 14 MRCOOL system listings say DIY.
  • On certified numbers, the Senville is the better unit. It rates 21.2 SEER2 to the MRCOOL's 17.5, so cooling costs $8.88 per million BTU against $10.76. The MRCOOL is a little better on heating (9 vs 8.7 HSPF2), which saves $0.72 per million BTU of heat. At that rate, saving $749.01 on heat would take about 1,040 million BTU, or 9.9 years of running flat-out.
  • Neither is built for hard winters. Neither is cold-climate rated. At 5°F the Senville is certified to deliver 6,600 BTU, 55% of its output at 47°F, and the MRCOOL 6,200 BTU, 52%. Where winters reach 5°F, plan on backup heat with either one.
  • MRCOOL's better DIY unit was not for sale new. MRCOOL's DIY 5th Gen 12,000 BTU (115 V) is certified at 23.5 SEER2 and 10.2 HSPF2 and is cold-climate rated, so it beats the Senville on every number. On October 17, 2026 Amazon offered it only through Amazon Resale, not as a new unit, so it is not compared here.
  • Refrigerant is not a reason to choose. AHRI lists both as R-454B, and both listings say so: the Senville in its spec table, the MRCOOL in its bullet points.

03 / Other sizes

Other sizes

MRCOOL's DIY Select is the line on this page at 12,000 BTU, and it is the match at 18,000 and 24,000 BTU too. Same rule: same size, same voltage, certified numbers for the exact model pair.

  • 18,000 BTU class, 230 V

    MRCOOL DIY Select

    17.3 SEER2 · 8.5 HSPF2 · 9,500 BTU at 5°F · No Amazon offer on October 17, 2026

    Senville LETO

    19.2 SEER2 · 9.6 HSPF2 · 11,500 BTU at 5°F · No Amazon offer on October 17, 2026

    Senville leads on every certified number. Neither 18,000 BTU kit had an Amazon offer on October 17, 2026; the 24,000 BTU pair below is the nearest in stock.

  • 24,000 BTU class, 230 V

    MRCOOL DIY Select

    16.5 SEER2 · 8.3 HSPF2 · 16,500 BTU at 5°F · $1,899.00 ($82.57 per 1,000 BTU)

    Check price on Amazon

    Senville LETO

    18.7 SEER2 · 9.3 HSPF2 · 17,000 BTU at 5°F, cold-climate, ENERGY STAR · $1,249.99 ($52.08 per 1,000 BTU)

    Check price on Amazon

    Senville leads on every certified number and on price per BTU, and only it is cold-climate rated. Only the MRCOOL is sold as DIY.

At 9,000 BTU, Senville's LETO 110 V (21.5 SEER2, 9 HSPF2, ENERGY STAR) was $699.99 on Amazon on 2026-10-17. We found no in-stock MRCOOL DIY 9,000 BTU 115 V listing to match it.

04 / Questions

Frequently asked

Senville or MRCOOL: which mini-split should I buy?
At 12,000 BTU on a household circuit: MRCOOL DIY Select if you will install it yourself, Senville LETO if a pro will. The Senville rates higher on cooling (21.2 vs 17.5 SEER2) and on heat at 5°F; the MRCOOL is a little higher on heating efficiency (9 vs 8.7 HSPF2). The Senville costs $66.67 per 1,000 BTU against $129.08 on 2026-10-17. [1][3]
Can I install a Senville mini-split myself?
Senville's listing says no: "Professional installation required." It ships with a 16 ft line set and says labor is not included. 11 of the 13 Senville listings we read on Amazon say a professional must install the unit. If you want to skip the vacuum pump and the HVAC technician, a quick-connect DIY kit like the MRCOOL DIY Select is built for that. [3][5]
Is the Senville LETO ENERGY STAR certified?
The 12,000 BTU LETO pair (SENL-12CD-OL + SENL-12CD-ILL) was not on ENERGY STAR's certified list on 2026-10-01. The 9,000 and 24,000 BTU LETO pairs were, and the 24,000 BTU pair is marked cold climate. The MRCOOL DIY Select 12,000 BTU pair (DIYS-12-HP-C-115A11-O + DIYS-12-HP-WMAH-115A13 - O) was not on the list either. [2]
How cold can the Senville LETO heat?
The listing says its heat pump is "functional up to 5F/-15C." AHRI certifies the 12,000 BTU LETO at 6,600 BTU at 5°F, 55% of its output at 47°F. The MRCOOL DIY Select keeps 52% (6,200 BTU). Neither is cold-climate rated. [3][1]
Which has the longer warranty?
Senville, on paper. MRCOOL's DIY Select listing says "2-year warranty"; MRCOOL's own warranty for the DIY Select gives 1 year on parts and 2 on the compressor, with no registration. Senville's listing says 5 years on the compressor; its bullet points say 5 years on parts, but its spec table says 2. Neither covers labor. Check the warranty terms with the seller before you buy. [3][4]
Which refrigerant do MRCOOL DIY and Senville use?
Both are R-454B on their AHRI certificates, and both listings name R-454B. [1][3]

How we did this

Method

We matched on size and voltage. Each pair is two single-zone wall units of the same certified size on the same circuit, each with a live Add to Cart button and a price on Amazon on 2026-10-17. Each listing prints a model code; we looked up the matching outdoor and indoor pair in the AHRI Directory and used the one active rating for it.

Senville's listings print a kit code (for example SENL-12CD-16, the kit with a 16 ft line set). AHRI certifies the same unit as the SENL-12CD-OL outdoor unit with the SENL-12CD-ILL indoor unit. The 110 V and 230 V 12,000 BTU LETO are different models; the listing on this page says 110 volts.

ENERGY STAR status is the program's own list, looked up by AHRI reference number. Refrigerant "per the listing" is only what the listing states. Price is the buy-box price on the listing page that day; it changes often.

Running cost per million BTU = 1,000 ÷ SEER2 (or HSPF2) × $0.1883/kWh. The payback figure divides the price gap by the heating-cost gap.

References

Sources

6 references · checked 2026-10-17
  1. 1

    AHRI Directory of Certified Product Performance, air-source heat pumps (program 99), active ratings

    queried by model number · 2026-10-01 · reference numbers in the table

  2. 2

    ENERGY STAR certified heat pumps (data.energystar.gov, dataset w7cv-9xjt)

    queried by AHRI reference number · 2026-10-01

  3. 3

    Amazon listings for the seven units on this page (specs read 2026-10-01, prices 2026-10-17)

    voltage, refrigerant, warranty and install note read 2026-10-01; price and seller 2026-10-17

  4. 4

    MRCOOL 5th Generation DIY Select Series limited warranty (PDF, rev. 03.31.26)

    read 2026-10-17 · 1 year parts, 2 years compressor, no registration

  5. 5

    Amazon mini-split listings: 161 system listings read on 2026-09-29

    install claim and refrigerant as each listing states them · 2026-09-29

  6. 6

    U.S. average residential electricity price used for running cost: $0.1883/kWh

    EIA · the same figure every running cost on this site uses