Resistor watts - 2w in place of a 3w? (1.2ohm resistor)

[Midcoastsurf]

I have a 3w 1.2ohm resistor in the power supply section of my chassis that I would like to replace (Kortek 2182).  Do I need to match these specs exactly or can I go up in wattage or up/down in ohms?

Thanks

[lilshawn]

no. keep it the same resistance. going up a little in wattage is usually not terribly bad, but i wouldn't recommend it.

resistor wattage rating specify a specific amount of heat generated by the resistor (and/or load) can be dissipated. bigger wattage means more heat can be generated before failure.

the resistor is likely downing a voltage for a component. if the component fails, the resistor will overheat and burn out. replacing it with a higher wattage rating will negate the burning out of the resistor when the part fails, and you end up burning out traces on the board instead.

try to keep things the same unless a part is chronically failing on you.  (and the cause is not another part)