A federal appeals court said it may consider a request to continue the fight over regional HVAC standards — this time as they apply to central air conditioners.

In an order released Wednesday, the U.S. Court of Appeals for the D.C. Circuit sent the petition from HARDI and the Air Conditioning Contractors of America to a merits panel, which will further consider the groups’ request.

The Heating, Air-Conditioning and Refrigeration Distributors International, along with the ACCA, is asking that because the proposed lawsuit settlement announced in January does not address the rules for heat pumps and central air conditioners -- it only covers indoor furnaces -- that take effect in 2015, that they be allowed to intervene and continue the fight.

The Air-Conditioning, Heating and Refrigeration Institute, the HVAC manufacturers’ lobbying arm, as well as the U.S. Department of Energy, opposes the move.

“Despite the government’s efforts to prevent our client, Heating, Air-conditioning, and Refrigeration Distributors International from making its case, the U.S. Court of Appeals for the D.C. Circuit has rightly afforded HARDI the opportunity to be heard,” said Dan Epstein, executive director of Cause of Action, which filed the suit on the association’s behalf. “By sending this case to a merits panel for further briefing, the D.C. Circuit has given HARDI a chance to explain how the Department of Energy’s abuse of the direct final rule process has real costs on thousands of HVAC distributors and therefore millions of Americans.”

The court also granted a stay of the furnace efficiency rules that were to take effect May 1. The Energy Department has said it will not enforce them while it waits for the court’s decision on the settlement.

Jon Melchi, HARDI’s director of government affairs, cheered the court’s decision.

“We have long believed that this regulation would have a negative impact on the many small businesses in the HVAC industry,” he said. “The DOE’s abuse of process in establishing the standard is a classic example of why the small business community is frustrated with Washington. We are pleased that we will have an additional opportunity to state our case and protect our members.”