After the success of its return to selling home appliances this year, the department store is now testing another big-ticket business: heating, ventilation, and air conditioning systems.

The test, first reported by the Dallas Morning News, is a partnership with HVAC company Trane and includes a display of the HVAC service near the major appliances at a few locations.

Under CEO Marvin Ellison, a former senior executive at Home Depot (HD), J.C. Penney rolled out big appliance departments at 500 of its 1,000 stores this year, which also started as a test. Penney hadn’t sold big home appliances since 1983.

The department store chain has been trying to get far more mileage from its large home goods sections, betting that selling washing machines will generate far more sales per square foot. Home goods used to account for 21% of Penney’s sales but have fallen to about 13%.

Ellison, the subject of a Fortune profile earlier this year, said last month that Penney stores with an appliance area would post comparable sales 2.5 to 3 percentage points higher than last year, an important boost given that Penney’s overall comparable sales in the third-quarter fell. (They also fell in the first quarter, raising concerns about the longevity of the chain’s turnaround.)

“We’re always exploring new ideas and partnerships that will entice customers to shop and spend more at J.C. Penney,” a company spokeswoman told Fortune in an e-mail statement.

Any foray into HVAC could bolster Penney’s move to win business in big-ticket home items from ailing mall-rival Sears (SHLD). And it moves Penney away from apparel, a declining category for most department stores, while giving it a category Macy’s (M) doesn’t have.