The Sacred Dhuni flame has been brought from Bangalore Mandir which got the orginal Dhuni flame from shirdi.

The udi from the dhuni is given as prasadam to all the devotees. this udi has the power to cure all diseases.
From the earliest days, Baba would give udi – holy ash from the dhuni – to his visitors. The healing power of Baba’s udi is well documented and there are numerous cases of people being healed of pain or sickness by taking Baba’s udi both before and since his mahasamadhi.
Baba would sometimes apply udi to his devotees when they arrived, or when they were taking leave of him, and he often gave out handfuls which he scooped up from the dhuni. The Sri Sai Satcharitra tells us that “when Baba was in a good mood” he sometimes used to sing about udi “in a tuneful voice and with great joy”: “Sri Ram has come, Oh he has come during his wanderings and he has brought bags full of udi.” Udi is still collected from the fire for distribution. Since this is a continuation of Baba’s own practice, and the udi comes from the very fire that Baba himself lit and tended, it is considered extremely sacred. Today a small tray of udi is kept for visitors near the steps.