The convection of air was studied under the magnetic field in a vertical cylinder heated from upper 1/3 side wall and cooled from lower 1/3 side wall with thermally insulated over the mid − level side wall and upper and lower end plates. The height of the cylinder was taken as 3 times of the cylinder radius. The electric coil of double radius of the cylinder was placed at various levels around the cylinder. Computations were carried out for a non-gravitational case with axially − symmetric assumptions at γ Ra = 1.232×104 and Pr = 0.71. γ represents the magnetic strength and Ra the magnitude of the temperature difference. Depending on the coil location, average heat transfer rates were found to change between unity and 6.4.