Coast AirCEP-121B

Portable AC

DOE certified cooling

6,500BTU/hSACC, DOE test

Single hose · CEER 6.7

Cools rooms up to 250 sq ft

DOE data as of 2026-11-03DOE record

Does it fit your room? ENERGY STAR sizing chart

Coast Air CEP-121B: certified to DOE at 6,500 BTU/h SACC, CEER 6.7, single hose. DOE data as of 2026-11-03.

Every model number on this record

Filed with DOE under basic model CEP-121B. A listing with any of these numbers is this unit.

Every model number filed under basic model CEP-121B, DOE data as of 2026-11-03
Model numberFiled by
CEP-121B (DOE basic model)Coast Air

How much does the Coast Air CEP-121B cost to run?

About 18¢ an hour of cooling, or $42.28 for 30 days at 8 hours a day (less once the compressor cycles off).

6,500 BTU/h SACC divided by a CEER of 6.7 is about 970 W while cooling. Electricity at 18.16¢/kWh, the US residential average for August 2026 (EIA Electric Power Monthly, table 5.6.A). Each 1¢/kWh you pay above or below 18.16¢ moves the 8 hour figure by 8¢.

How does the Coast Air CEP-121B rank in its DOE class?

In its DOE class (single hose portable ACs), 171 models have a matched Amazon listing. 120 of them have a higher CEER than its 6.7, which is 8% below their median of 7.3. On cost, the same 6,500 BTU/h at their median CEER would cost about $38.81 for 30 days at 8 hours, $3.48 less than this one.

Portable ACs that cool 250 sq ft (170 with a listing)

Among 1,044 single hose portable ACs

Cooling (SACC)6,500

Higher than 299 of 1,044. 9 others share 6,500.

2,00016,000 BTU/h

Efficiency (CEER)6.7

Higher than 220 of 1,044. 13 others share 6.7.

4.413.4

Three to compare with

From models with a matched listing.

  • Within 1,000 BTU/h of its size, highest CEER

    Antarctic Star AC7290-10K5,500 SACC

    Up to 150 sq ft, single hose, CEER 7.9: about 15% less power for the same cooling.

  • Nearest size in its class with a higher CEER

    KOMORE FDP29-202AZWV1R36,500 SACC

    Up to 250 sq ft, single hose, CEER 6.9.

  • Nearest bigger unit

    Hisense HAP0825TWD8,000 SACC

    Up to 350 sq ft, dual hose, CEER 13.5.

DOE record

Cooling

Cooling capacity (SACC)
6,500 BTU/h
Efficiency (CEER)
6.7 Btu/Wh

Build

Hose setup tested
Single hoseFiled as Single-duct
Heating function
No
Condensate removal
Auto-evaporation
Variable speed
No

Record

DOE basic model
CEP-121B
DOE class
Single hose portable ACs
Brands on the filings
1
In DOE's list since
2026-11-02first snapshot we hold

Questions

What is the Coast Air CEP-121B's real BTU?
It's certified to DOE at 6,500 BTU/h SACC (seasonally adjusted cooling capacity), the rating DOE requires for portable ACs. A box figure labeled ASHRAE is usually higher for the same unit because it comes from a different test: SACC vs ASHRAE.
Is it single hose or dual hose?
It was tested as a single hose unit, per the DOE record.
How big a room does it cool?
About 250 sq ft. ENERGY STAR's sizing chart calls for 6,000 BTU/h in rooms up to 250 sq ft. A sunny room, a kitchen or a high ceiling needs more.
How much does the Coast Air CEP-121B cost to run for 8 hours?
About $1.41 for 8 hours of cooling: roughly 970 W at 18.16¢/kWh, the US residential average for August 2026 (EIA).