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Costway 18000 BTU 21 SEER2 Mini Split Air Conditioner & Heater

Costway 18000 BTU 21 SEER2 Mini Split Air Conditioner & Heater

Best price now

$664.99at eBayChecked Nov 9

Compared across 3 stores. Prices are checked against each store and labelled with when. Store links may earn us a commission.

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Price facts

  • Last seen at $664.99 at eBay on Nov 9.
  • Checked at 3 stores.

Our take on the Costway 18000 BTU 21 SEER2 Mini Split Air Conditioner & Heater

The Costway 18000 BTU Mini Split is a single-zone wall-mounted heat pump that cools and heats up to about 1,250 sq ft. Its 21 SEER2 rating and 1.5-ton capacity put it in line with name-brand inverter splits, and it runs as quietly as 28 dB on low. It has eight fan speeds, a washable filter and a claimed heating range down to -4°F. It suits homeowners adding zone comfort to a large room or open plan without ductwork. The catch is that it is a budget-brand unit sold without a licensed installer network, so warranty support and parts availability are weaker than Mitsubishi, Daikin or LG, and the line set and mounting hardware are basic.

Best forLarge living rooms and open-plan spaces up to about 1,250 sq ftHomeowners adding a single-zone heat pump without ductworkBuyers who want inverter efficiency at a lower brand premiumMild-to-cold climates needing heat down to -4°F
Pros
  • 21 SEER2 inverter efficiency rivals big-name single-zone splits
  • Cools and heats one zone up to roughly 1,250 sq ft
  • Quiet operation at 28 dB on the lowest of eight fan speeds
  • Washable filter keeps running costs down
  • Heats in temperatures as low as -4°F
Cons
  • No NRTL listing shown, which some inspectors and rebate programs require
  • 230V hardwired install is not a DIY plug-in job
  • Budget brand: parts, warranty service and installer support trail major brands
  • Single zone only, and the 6.5 ft hose limits placement flexibility

Costway 18000 BTU 21 SEER2 Mini Split Air Conditioner & Heater prices at every store

  • Lowe'sNew

    In stock

    $719.98Free shippingChecked Nov 9
    Visit Lowe's
  • WalmartNew

    In stockSold by Costway

    $901.99Checked Nov 9
    Visit Walmart
  • eBayNew

    Availability unknownSold by minglun_suny (99.6% positive, 5,200 ratings)Returns: Set by the eBay seller; the eBay Money Back Guarantee covers an item that doesn't arrive or isn't as described.

    $664.99Free shippingChecked Nov 9
    Visit eBay

Store links may earn us a commission. Some prices via Klarna.

Costway 18000 BTU 21 SEER2 Mini Split Air Conditioner & Heater price history

Lowest price we've seen: $719.98 on Nov 9 at Lowe's. Tracked across 2 stores since Nov 9.

What reviewers say

Owner feedback on Costway mini splits is mixed.

What people mention
  • NoisePraisedOwners say the indoor unit runs quietly, especially on the lower fan speeds.
  • InstallationCriticisedBuyers report the manual is thin and the 230V hardwired setup is best left to an HVAC tech.
  • EfficiencyPraisedThe 21 SEER2 inverter rating draws praise for running costs against older units.
  • HeatingMixedHeating output is fine in mild cold, but owners in hard freezes question the -4°F claim.

Specifications

Coverage Area
1250 sq ft
Mount Type
Wall Mount
Energy Efficiency Rating
21
Volts
230 Volts
Decibel Rating
28 dB
Filter Type
Washable
Dimensions
39.76 x 8.66 x 12.40 in

Questions and answers

Is 18,000 BTU enough for my room?
It is rated for about 1,250 sq ft in average conditions. Hot climates, poor insulation or lots of glass may need a larger unit or a load calculation.
Does it need a special electrical circuit?
Yes. It runs on 230V and needs a dedicated circuit sized to the unit, installed by a licensed electrician or HVAC tech.
Can I install it myself?
The indoor and outdoor units can be mounted DIY, but the refrigerant lines need vacuuming and charging by a certified technician to keep the warranty valid.
How does it compare with a Mitsubishi or Daikin split?
Efficiency and noise specs are close on paper. The big brands beat it on installer network, parts availability and warranty service.
What comes in the box?
Indoor and outdoor units, a 6.5 ft connection hose, remote and basic mounting hardware. Line set length and brackets may need to be bought separately.
Does it qualify for rebates?
Check with your utility. Many rebate programs require NRTL listing and certified installation, and this unit does not show an NRTL listing.
Where is the Costway 18000 BTU 21 SEER2 Mini Split Air Conditioner & Heater cheapest?
At eBay, for $664.99, as of our latest check.
Where can I buy the Costway 18000 BTU 21 SEER2 Mini Split Air Conditioner & Heater?
3 stores we checked sell it, including eBay, Lowe's, Walmart.

Stores we've priced the Costway 18000 BTU 21 SEER2 Mini Split Air Conditioner & Heater at

  • Lowe's deals and prices
  • Walmart deals and prices

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Recommended Use
Residential
Has Nrtl Listing Certification
N
Minimum Indoor Temperature
-4°F
Number Of Speeds
8
Number Of Settings
7
Number Of Zones
1
Power Rating
1.5 Tons
Hose Length
6.5 ft