* Environmentalists and industry welcome deal
* Step towards international agreement - Green Party
* Deal needs formal endorsement to become law
BRUSSELS, Dec 16 (Reuters) - The European Union on Monday reached a tentative deal on limiting the use in fridges and air conditioners of fluorinated gases that have a global warming potential thousands of times greater than carbon dioxide.
Two decades after international action led to the phasing out of ozone-depleting chlorofluorocarbons (CFCs), the European Commission last year proposed a law to eliminate the climate-harming "F-gases" that replaced CFCs.
Under Monday's deal, the new rules introduce a cap to achieve a 79 percent reduction by 2030 on the group of gases known as hydroflurocarbons (HFCs).
The rules also include bans on the use of HFCs in new equipment in some business sectors by 2022 and prevent their use for servicing and maintainence of old equipment.
The agreement on Monday needs to be endorsed by EU diplomats and then the European Parliament and EU ministers to become law, EU officials said.
F-gases, used as coolants in air conditioning and in domestic, supermarket and industrial refrigeration, were introduced as a solution easily acceptable to industry because their production chain resembled that for CFCs.
But their global-warming potential, up to 23,000 times more than carbon dioxide, led the Commission to push for natural non-synthetic alternatives such as ammonia or CO2, which can have high cooling properties when used in refrigeration.
Environmental campaigners and Green politicians had tried to get a more sweeping ban but said that the agreement still represented progress.
From the European Parliament, Bas Eickhout, a member of the Green Party, said that negotiations had produced "a classic compromise".
He added that it is a step towards the greater prize of a global deal and called on China and the United States to follow the EU's lead.
The refridgeration, air-conditioning and heat pump industry, represented by the European Partnership for Energy and the Environment (EPEE), also welcomed the deal.
"The phase-down will steer innovation and help industry to move towards alternative solutions in a safe and efficient way," Andrea Voigt, EPEE director general, said in a statement.
Provided the new rules are endorsed, they should become applicable from 2015.
In contrast to a drop in other emissions, F-gases have risen in the European Union by 60 percent since 1990. They leak into the atmosphere from production plants and during the operation and disposal of products and equipment that contain them.
(Reporting by Barbara Lewis; Editing by David Goodman)