Tungurahua has been spitting out ash and lava for three days, and emitting loud explosions. It returned to life in 1999, after a century of inactivity.
So far there have been no injuries, but some villagers are reluctant to leave their homes and livestock.
President Alfredo Palacio has announced $4.9m in aid, after touring the affected area at the weekend.
Nearby towns have been covered in volcanic ash, as the wind carried the dust up to 120km (75 miles) from Tungurahua.
There have been 24 explosive cycles since Saturday, according to an official at the country's Geophysical Institute.
Some locals have refused to move away from the area.
"They said to evacuate but we're not going to leave because we're not going to throw away the animals, the houses," said Manuel Rosero, wearing a handkerchief over his face against the ash in the air.
Tungurahua is 5,029 metres (16,500ft) high, and is located 135km (85 miles) south of the capital, Quito.
BBCGüncelleme Tarihi: 20 Eylül 2018, 18:16