SplitAtlas

Senville / LETO Series

Senville LETO 18k R-454B 208/230V Mini-Split

Certified capacity
18,000 BTU/h[3]
SEER2
19.2 SEER2[3]
Heating floor
5 F[1]
Voltage
187-253[1]
Install path
Professional install / DIY-marketed

The LETO 18k covers an open-plan room at SEER2 19.2 with a +5F heating floor. Note the line's efficiency falls as capacity rises - 21.5 at 9k down to 19.2 here - so the larger LETO systems are working harder for less. Combined with the +5F rating, this suits a cooling-led installation only; the AURA 18k is the system for anywhere with a winter.

1 zoneProfessional install / DIY-marketedCurrent

Refrigerant generation

R-454B - current-generation refrigerant

Paid link

$1,000 / Fresh price - checked Jul 24, 2026

Check price at Senville

Need this installed?

Get installation quotes
Error Codes
Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL) mini-split heat pump indoor wall unit and outdoor condenser

Image: Senville

Data completeness: 88%
Last sourced
Aug 17, 2026

SplitAtlas score

7.6 / 10

Methodology
Cooling efficiencyBottom quartile

(19.2 SEER2) among 18k systems

Heating efficiencyBelow average

(9.6 HSPF2) among 18k systems

Cold-weather performanceBottom quartile

(61.2% heat retained at 5F; 5 F heating floor) among 18k systems

NoiseBelow average

(24 dBA indoor min / 56 dBA outdoor) among 18k systems

WarrantyBottom quartile

(5 yr parts / 5 yr compressor) across the catalogue

Installation accessibilityBelow average

(DIY-marketed; 25 ft precharged; 16 ft included line set) across the catalogue

Feature setBelow average

(4 verified features) across the catalogue

Price-to-performanceTop quartile

($1,000 median retail) among 18k systems

Documentation & partsTop 10%

(9 manuals; spec sheet; 51 error-code rows; parts channel) across the catalogue

Key ratings

Rated cooling

18,000BTU/h[3]

Rated heating

18,800BTU/h[3]

Buyer review snapshot

Install difficulty

Professional flared-line install
  • Electrical: 187-253V; MCA 15 A; breaker/fuse 20 A.
  • Line set: Flared line connections; precharged 25 ft; included 16 ft; max 25 ft.

Alternatives

Availability and price context

  • Verified current price: $999.99 at Senville; availability in_stock; checked Jul 24, 2026.

Source date

Model data sourced
Aug 17, 2026
Page reviewed
Jul 24, 2026
Source-backed records
4
Newest source retrieved
Aug 17, 2026

Warranty tiers

Warranty: 5 years parts and compressor as standard.

Review methodology

Strengths

  • Open-plan capacity at Senville's entry pricing.

Weaknesses

  • SEER2 19.2 - efficiency drops as the LETO line scales up.
  • +5F heating floor.

Climate suitability

Minimum heating ambient
5 F[1]
Rated heating at 5F
11,500 BTU/h[3]
Rated heating at 17F
14,000 BTU/h[3]
Rated heating at 47F
18,800 BTU/h[3]

Specifications

Show
Manufacturer
Senville
Brand
Senville
Product line
LETO Series
Model number
SENL-18CD-ILL indoor / SENL-18CD-OL outdoor
Indoor unit model
SENL-18CD-ILL
Outdoor unit model
SENL-18CD-OL
Number of zones
1
Max indoor units
not published
Rated cooling capacity
18,000 BTU/h[3]
Rated heating capacity
18,800 BTU/h[3]
Voltage
187-253[1]
MCA
15 A[1]
Maximum fuse or breaker size
20 A[1]
Breaker needed
not published
SEER2
19.2 SEER2[3]
EER2
10.8 EER2[3]
HSPF2 (Region 4)
9.6 HSPF2[3]
HSPF2 (Region 5)
not published
COP
not published
COP at 47F
not published
COP at 5F
2.14 COP[3]
Minimum outdoor heating temperature
5 F[1]
Minimum outdoor cooling temperature
not published
Maximum outdoor temperature
not published
Indoor noise range
50.5 / 45 / 36 / 24[1]
Outdoor noise rating
56 dBA[1]
Indoor weight
24.47 lb[1]
Outdoor weight
72.31 lb[1]
Refrigerant
R-454B[3]
Refrigerant charge
not published
Manufacturer coverage
not published
Line-set size
not published
Included line-set length
16 ft[1]
Maximum line-set length
25 ft[1]
Max line set per indoor
not published
Maximum elevation difference
not published
Max height between indoor units
not published
Wi-Fi support
supported[1]
Energy Star status
Not ENERGY STAR certified[4]
AHRI certification number
215735290[3]
Warranty
Standard: 5 yr parts / 5 yr compressor (published warranty terms). 5 Years Compressor / 5 Years Parts
Install path
Professional install / DIY-marketed
Marketing install label
DIY-marketed
Retail price
$999.99
Available retailers
Senville
Manual links
LETO 18,000 BTU ahri certificate, AHRI Appendix M1 public detail record 215735290, LETO 18,000 BTU energy guide, ENERGY STAR exact-match row check for AHRI 215735290, Senville LETO Installation Manual, LETO 18,000 BTU owner manual, HVACDirect exact search outcome for SENL-18CD-OL / SENL-18CD-ILL, LETO 18,000 BTU service manual, LETO 18,000 BTU Senville product-page specifications
Specification sheet
LETO 18,000 BTU Senville product-page specifications
Last sourced date
Aug 17, 2026

Retail purchase context

Some retailer links may earn us a commission at no extra cost; paid relationships never change scores or recommendations. Affiliate disclosure

Paid link

Check price at Senville

$1,000 / Fresh price - checked Jul 24, 2026

Parts and filters

Fits Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL). Part numbers and fit notes identify compatibility only; no manufacturer endorsement is implied.

air-filter

Indoor filters (SENL/18CD/IX - SENL/18CD/IY - SENL/18CD/ILL)

Fits
Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL)
OEM part number
PL18195
Fit note
Fits SENL-18CD-ILL / SENL-18CD-OL. Senville publishes this LETO ILL-family filter SKU and sells it directly at https://senville.com/18000-btu-leto-indoor-filters-senl-18cd-ix/. HVACDirect did not expose an exact Senville filter page, so no affiliate offer is attached.
Source
Senville LETO filter product page, Product details, page product page (PL18195)

remote-control

Remote control (ILL)

Fits
Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL)
OEM part number
PAR669
Fit note
Fits SENL-18CD-ILL / SENL-18CD-OL. Senville sells the ILL replacement remote directly at https://senville.com/remote-control-ill/. HVACDirect did not expose an exact Senville remote page, so no affiliate offer is attached.
Source
Senville Remote Control (ILL), Product details, page product page (PAR669)

smart-wifi-usb-kit

Senville Smart WiFi USB Kit for Mini Split, Works with Alexa

Fits
Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL)
OEM part number
SEN20-ACK1T
Fit note
Fits SENL-18CD-ILL / SENL-18CD-OL. Senville publishes SEN20-ACK1T for compatible post-2019 indoor units and sells it directly at https://senville.com/senville-smart-wifi-usb-kit-for-mini-split-works-with-alexa/. HVACDirect did not expose an exact Senville Wi-Fi kit page, so no affiliate offer is attached.
Source
Senville Smart WiFi USB Kit for Mini Split, Works with Alexa, Product details, page product page (SEN20-ACK1T)

line-set-installation-kit

25 ft flared line-set installation kit - 1/4 x 1/2

Fits
Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL)
OEM part number
PJX-2-75E
Fit note
Fits SENL-18CD-ILL / SENL-18CD-OL. Use this size for 18k Senville indoor units or matching multizone ports. Senville sells the PJX-2-75E line set directly; HVACDirect was verified as a live exact-dimension 25 ft install-kit page on 2026-08-01. First-party path: https://senville.com/25-ft-insulated-line-set-1-4-and-1-2/.
Source
Senville 25 Ft. Insulated Line Set - 1/4 and 1/2, Technical Specifications, page product page (SKU | PJX-2-75E)

Some retailer links may earn us a commission at no extra cost; paid relationships never change scores or recommendations. Affiliate disclosure

Paid link

Check price at HVACDirect
Replacement Parts & Filters

Electrical requirements

Show
Voltage
not published
Voltage range
187-253[1]
Phase
single-phase[1]
Frequency
60 Hz[1]
MCA
15 A[1]
Breaker needed
not published
Maximum breaker size
not published
Maximum fuse size
20 A[1]
Maximum cooling current
not published
Maximum heating current
not published
Manufacturer wire notes
14*4 AWG[1]

Installation considerations

Show
Liquid line
not published
Suction line
not published
Line connection type
Flared line connections[2]
Precharged length
25 ft[1]
Included line-set length
16 ft[1]
Maximum line-set length
25 ft[1]
Max line set per indoor
not published
Max height between indoor units
not published
Indoor dimensions
37.99 in W x 12.56 in H x 8.46 in D[1]
Outdoor dimensions
31.69 in W x 21.81 in H x 12.99 in D[1]
Indoor weight
24.47 lb[1]
Outdoor weight
72.31 lb[1]
Drain size
not published

Related systems and guides

Frequently asked questions

Can I install the Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL) myself, or do I need a pro?
Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL) is built for professional installation: the line set must be flared, evacuated, and charged, which requires EPA-certified refrigerant handling. Installing it outside the manufacturer's requirements can void the warranty, so budget for a qualified HVAC installer.
Will the Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL) keep heating in a cold winter?
The manufacturer publishes 11,500 BTU/h of heating output at 5F. Rated heating operation extends down to 5 F. Certified heating efficiency is 9.6 HSPF2. Match those numbers against your climate's design temperature - in cold regions, output at 5F matters far more than the nameplate capacity measured at 47F.
What electrical circuit does the Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL) need?
Published electrical requirements: 187-253 voltage, 15 A minimum circuit ampacity, and 20 A maximum breaker or fuse sizing. Confirm the final circuit against the unit nameplate and local code with a licensed electrician.
How far can the outdoor unit be from the indoor head?
The published maximum line-set length is 25 ft, and the included line set comes pre-charged for 25 ft. Longer runs than the included set allows typically mean added refrigerant and a pro visit, so measure the planned routing before ordering.
What warranty does the Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL) carry?
The manufacturer publishes these warranty tiers: Standard: 5 yr parts / 5 yr compressor (published warranty terms). Registration requirements and proof of qualified installation commonly affect coverage, so read the warranty terms before install day.

Data sources

Show
  1. Senville: Senville LETO 18,000 BTU R-454B 208/230V (SENL-18CD-ILL / SENL-18CD-OL) official product pageSourced - manufacturer product page

    Covers Frequency, Maximum fuse size, Minimum circuit ampacity, Phase, Manufacturer wire notes, Voltage range and more

  2. Senville: Senville LETO Installation ManualSourced - manufacturer technical document

    Covers Line connection type

  3. AHRI certificate #215735290 - search the AHRI DirectorySourced - AHRI directory

    Covers AHRI certification number, Rated cooling capacity, COP at 5F, EER2, Rated heating capacity, HSPF2 (Region 4) and more

  4. ENERGY STAR: ENERGY STAR exact row check for AHRI 215735288Sourced - Energy Star listing

    Covers Energy Star status

Last updated

Jul 24, 2026