Here are a few hot springs in Andhra Pradesh. They are in the Godavari Basin geothermal zone. There are reported to be 13 hot springs in this area though the whereabouts of most of them remains a mystery for now. I'll add on more if I find any of them.
Ushnagundam,
This hot water spring is a pilgrimage place on the bank of the river between 4 and 6 klms from the town of Bhadrachalam. There are hot springs in the bed of the river over a certain area of about 100 square yards and a pit dug at any spot in that area will produce hot water.
The Ramayana records this to be a site visited by Sita, Rama and Lakshman. Lakshman got hot water from the spring here for Sita to bathe in.
The Brahmanda Puranam says these hot springs formed as a result of the celestial fire offered by the divine serpent "Adi Seshu".
Bhadrachalam nearby is situated on the banks of Godavari River and the jungle around there was the site of Rama's retreat. Parnasala (32 km away) is where he built a hut for himself and Sita, and it was from there that Sita was abducted by Ravana.
At Bhadrachalam one can taste the prasadam (food offered at the Rama temple) which is sold outside the main entrance and makes a good breakfast.
The Devastanam (temple owned) accommodation is available. The State run Punnami Bhadrachalam has dormitories for 150 rupees.
The nearest railway station is Bhadrachalam Road, also known as Kothagudem , 40 km from Bhadrachalam. It takes approximately 50 minutes to travel from Railway Station to Bhadrachalam by bus and the fare is about Rs 20. This is an area patrolled by plains clothes police seeking out the Naxalite terrorists there.
Gundala
Gundala town, located further from Bhadrachalam, in a north west direction, is a place mentioned to have a hot spring. It is on the Kinnerasani river.
It is said in the Brahma Purana, that the sacred trio of Gods, Brahma, Vishnu, and Shiva all bathed in this hot spring in the winter.
Manuguru
A hot spring is located here, at Manuguru.
In geothermal studies Manuguru and Bugga hot springs are usually referred to together. For instance, 'a heat exchanger has been designed to dehydrate onions using the thermal waters of Bugga and Manuguru'. Both these springs are considered be promising areas for geothermal energy development.
Manuguru is a town in the Khammam district. Going north from Bhadrachalam Station, Manuguru Railway Station is the next main station you come to.
Bugga
Bugga is the other hot spring usually referred to along with Manuguru
Bugga is 27 klms from Kurnool. There are natural rock formations on the way from Kurnool to Bugga well worth seeing.
Kurnool is a centre of Hindu pilgrimage and is surrounded by hill resorts. It is on the Hyderabad to Bangalore railway line.
Hatakeswaram, Srisailam
There are two hot springs at Hatakeshwaram and a temple dedicated to Lord Shiva. The lingam of the temple was originally made of gold.
Siva appeared here orginally to a potter in an Atika ( a piece of pot) and hence the place was named Atikeswaram, later becoming Hatakeswaram.
Shankaracharya did his penance here and composed the Sivanand Lahari. During the penance he was approached by a Kabalika, called Kirakashan. The Kapalikas were a sect who lived in the burial grounds and prayed to God through human and animal sacrifices. They were against Advaita sprituality which preached love and affection and shunned violence. Kirakashan asked Sankara to give his body as a human sacrifice to Shiva. Sankara agreed to this request. Kirakashan was about to cut off Sankara's head when Lord Narasimha appeared in the form of a lion and killed Kirakashan.
The springs are 3 km from Srisailam in the district of Kurnool. Srisailam has one of the largest Tiger Reserves in India. The terrain is rugged and winding gorges slice through the area. As a pilgrimage place all food is vegetarian and no smoking or drinking is allowed.
Mahanandi
The warm mineral water here is famous for its curative properties, and though not exactly hot it is still an interesting place to visit.
The Mahanandiswara Swamy temple here is an important shrine, famous for its warm pool which one can dip into and for its Shiva lingam which one can pray to and even touch (normally one is not allowed to touch holy lingams). All people can touch and worship the Lingam. It is believed that by taking a holy bath here all the sins of the pilgrims are vanquished
Mahanandi is a picturesque village surrounded by thick forests in the Nallamala Hills.
The largest Nandi statue in the world is here. Nandi is the bull that Shiva rides upon.
Mahanandi is one of the Nava Nandis. Surrounding Mahanandi within a 15-km diameter range, 9 temples of the Nandi Bull are present.
The Bellum caves are also nearby. Jain and Buddhist monks stayed at these caves centuries ago. Many Buddhist relics have been found inside the caves (these relics are now housed in a museum at Ananthapura). There is a giant statue of Buddha near the caves.
Banganapalle, famous for its mangoes is 20 klms away. Kurnool is 80klms away.