Hello Seema,

Though you are still within the specified input voltage range ( 35V ) I still think 29V is way too high as this severly limits the current that you can draw from the regulator before the internal safety circuit cuts in.

Dropping this with a resistor is possible only if your load is going to reamin constant - in many cases it may not. ANd in any case that resistor is going to heat up.

Do the following : At the output of the 7815 connect a Red LED with 1.2 K / 0.5W resistor to ground. This will ensure that regulator has a minimum load always ( about 10mA+). And you know the circuit is alive. Also connect a 0.1MFD disc or tantalum between the output and ground VERY NEAR to the regulator to supress any sporadic oscillations.

And finally fit the regulator on a GOOD heatsink with LOTS of heatsink paste.

Tell what happened.

Raghu