A fuel bowser was burnt out at the Peisley Street BP service station, opposite Wade Park, just after 10.30pm on Sunday night.

It followed a car burnt out on Clinton Street on Saturday.

Central West Police District Inspector Scott Rayner said police suspected the fire was deliberately lit after an unknown offender approached the bowser closest to the building.

He said the witness was driving past at the time and noticed the fire burning.

"That person stopped and used a fire extinguisher to reduce the fire," he said.

Emergency services were called and Fire and Rescue NSW quickly extinguished the blaze.

Inspector Rayner said bystanders were cleared within a 30-metre radius in case more equipment burst into flame, however damage was limited to the single bowser.

The BP is currently unmanned and accepts card only and he said most petrol station operators cut off fuel supplies when they closed, but commended the witness for fighting the fire.

No injuries occurred during the incident.

"There would have been some ignitable liquid there and that person wouldn't have known the extent of the fire," Inspector Rayner said.

"I would certainly say it was a brave thing to do."

Police continued inquiries on Monday to find the person responsible for lighting the fire by canvassing the area and sourcing CCTV footage.

"The witness didn't see anybody," Inspector Rayner said.

Anyone with information about the incident is urged to call Orange police on 6363 6399 or Crime Stoppers on 1800 333 000.

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