Our take in 30 seconds
Best for: cold and very cold climatesStrengths
- Keeps 91% of its heat at 5°F, so backup heat rarely runs
- Heating efficiency (HSPF2 10.6) beats 87% of models
- Cooling efficiency up to SEER2 23, better than 87% of models
- Variable-speed compressor: quieter, steadier temperatures and better humidity control
Good to know
- Uses R-410A, a refrigerant being phased down; future service may cost more
- Efficiency depends on the indoor unit: SEER2 ranges 17–23, so ask which pairing you're quoted
Running-cost calculator
Pre-filled with EIA prices · edit any fieldUses the base certified SEER2 (17) and HSPF2 (10.6). Assumes the unit is correctly sized. How we calculate.
Heating capacity as it gets colder
A heat pump's output falls as outdoor temperature drops. This is the certified heat output of the LG ARUM036GSS5 at the three ENERGY STAR test temperatures (cooling capacity is 36,000 BTU/h for reference).
Retention at 17°F: 63% · at 5°F: 91%. Learn how to use these numbers in our cold-climate guide.
Estimated running cost in every state
Same unit, very different bills: from about $996 a year in Louisiana to $4,474 in Alaska, driven by local electricity prices and how much heating or cooling the climate needs. Click a column to sort.
| State | Price | Heating | Cooling | Total / yr |
|---|---|---|---|---|
| Louisiana | 12.87¢ | $450 | $545 | $996 |
| Florida | 14.99¢ | $337 | $762 | $1,099 |
| Mississippi | 14.43¢ | $649 | $550 | $1,199 |
| Arizona | 15.05¢ | $527 | $701 | $1,228 |
| Nevada | 12.72¢ | $763 | $485 | $1,248 |
| Tennessee | 13.42¢ | $939 | $369 | $1,309 |
| Washington | 14.63¢ | $1,244 | $108 | $1,352 |
| North Carolina | 14.95¢ | $972 | $412 | $1,383 |
| Texas | 15.91¢ | $716 | $674 | $1,390 |
| Arkansas | 14.37¢ | $934 | $456 | $1,391 |
| South Carolina | 15.76¢ | $867 | $534 | $1,401 |
| Georgia | 15.90¢ | $874 | $539 | $1,413 |
| Oregon | 15.92¢ | $1,274 | $152 | $1,425 |
| Kentucky | 13.80¢ | $1,104 | $321 | $1,425 |
| Alabama | 16.33¢ | $898 | $553 | $1,451 |
| Oklahoma | 14.82¢ | $1,037 | $471 | $1,508 |
| Utah | 13.31¢ | $1,264 | $254 | $1,518 |
| New Mexico | 16.51¢ | $1,238 | $350 | $1,588 |
| Idaho | 13.37¢ | $1,404 | $198 | $1,602 |
| Nebraska | 13.54¢ | $1,422 | $258 | $1,680 |
| Virginia | 17.64¢ | $1,323 | $411 | $1,734 |
| Missouri | 16.02¢ | $1,362 | $373 | $1,735 |
| West Virginia | 16.31¢ | $1,468 | $276 | $1,744 |
| Kansas | 15.47¢ | $1,392 | $360 | $1,753 |
| Wyoming | 14.43¢ | $1,804 | $153 | $1,957 |
| California | 29.75¢ | $1,339 | $630 | $1,969 |
| Colorado | 17.17¢ | $1,717 | $255 | $1,972 |
| Delaware | 18.70¢ | $1,590 | $396 | $1,986 |
| Indiana | 17.02¢ | $1,702 | $306 | $2,008 |
| North Dakota | 13.31¢ | $1,930 | $127 | $2,057 |
| Montana | 15.57¢ | $1,946 | $148 | $2,095 |
| South Dakota | 15.15¢ | $1,894 | $209 | $2,102 |
| Iowa | 17.06¢ | $1,962 | $271 | $2,233 |
| Ohio | 19.38¢ | $1,938 | $328 | $2,266 |
| Maryland | 21.40¢ | $1,819 | $453 | $2,272 |
| Illinois | 19.32¢ | $2,029 | $327 | $2,356 |
| Minnesota | 17.20¢ | $2,322 | $200 | $2,522 |
| Pennsylvania | 21.77¢ | $2,177 | $369 | $2,546 |
| Wisconsin | 19.41¢ | $2,426 | $247 | $2,673 |
| District of Columbia | 25.98¢ | $2,078 | $605 | $2,684 |
| New Jersey | 24.61¢ | $2,215 | $469 | $2,684 |
| Hawaii | 47.18¢ | $118 | $2,598 | $2,716 |
| Connecticut | 24.51¢ | $2,696 | $337 | $3,033 |
| Michigan | 22.99¢ | $2,759 | $292 | $3,051 |
| Vermont | 23.84¢ | $3,099 | $227 | $3,326 |
| Rhode Island | 28.18¢ | $3,100 | $358 | $3,458 |
| New York | 28.65¢ | $3,152 | $394 | $3,546 |
| New Hampshire | 27.64¢ | $3,455 | $293 | $3,748 |
| Massachusetts | 30.48¢ | $3,505 | $387 | $3,892 |
| Maine | 32.11¢ | $4,174 | $272 | $4,446 |
| Alaska | 29.41¢ | $4,412 | $62 | $4,474 |
Similar-size alternatives
Other mini-split / multi-split units within ±15% of this model's cooling capacity, sorted by efficiency. Cost difference is versus the LG ARUM036GSS5 at U.S.-average rates.
| Model | Cooling BTU/h | SEER2 | HSPF2 | 5°F kept | Est. yearly cost | |
|---|---|---|---|---|---|---|
| Mitsubishi Electric MXZ-SM36NLHZ-** | 36,000 | 16–23 | 12 | 100% | $1,466 (−$409) | Compare |
| Mitsubishi Electric MXZ-SM36NL-** | 36,000 | 17.5–23 | 11 | 71% | $1,494 (−$382) | Compare |
| Samsung AC036DXSCCG | 36,000 | 18.7–22 | 10.6 | 100% | $1,481 (−$395) | Compare |
| Mitsubishi Electric PUZ-AK36NLHZ2*** | 36,000 | 18.1–23.3 | 10.5 | 100% | $1,449 (−$427) | Compare |
| Mitsubishi Electric PUZ-AK36NL2*** | 36,000 | 18.1–23.3 | 9.8 | 64% | $1,524 (−$352) | Compare |
| Mitsubishi Electric PUZ-AK36NL*** | 36,000 | 18.1–23.3 | 9.8 | 58% | $1,643 (−$233) | Compare |
Full specifications
| Brand | LG |
| Outdoor model | ARUM036GSS5 |
| Certified by | LG Electronics, Inc. |
| Product type | Mini-split / multi-split |
| Compressor | Variable-speed (inverter) |
| Refrigerant | R-410A |
| Cooling capacity | 36,000 BTU/h |
| Nominal size | 3 tons |
| SEER2 (certified range) | 17 – 23 |
| EER2 (best) | 15.5 |
| HSPF2 (best) | 10.6 |
| Heating capacity @ 47°F | 53,000 BTU/h |
| Heating capacity @ 17°F | 33,400 BTU/h |
| Heating capacity @ 5°F | 48,000 BTU/h |
| COP @ 5°F | 1.83 |
| ENERGY STAR cold-climate | Yes |
| Certified indoor pairings | 3 |
| Latest certification | 2026-01 |
Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), retrieved November 7, 2026. Capacities and HSPF2 are the highest values across certified pairings; confirm your exact system's AHRI reference number with your installer.
Frequently asked questions
How much does the LG ARUM036GSS5 cost to run per year?
At the U.S. average residential electricity price of 18.16¢/kWh and typical national heating and cooling hours, we estimate about $1,876 per year ($1,453 heating, $423 cooling). It ranges from about $996 in Louisiana to $4,474 in Alaska.
Does the LG ARUM036GSS5 work in cold weather?
Yes. It is ENERGY STAR cold-climate certified and delivers 48,000 BTU/h at 5°F, 91% of its 47°F capacity, with a COP of 1.83 at 5°F.
What size is the LG ARUM036GSS5?
It is rated at 36,000 BTU/h of cooling, roughly 3 tons, and 53,000 BTU/h of heating at 47°F. Proper sizing should be confirmed with a Manual J load calculation.