Have 12volt 2.2am battery am running 12volt 14watts TV... how long will the power last,in hours please

The calculation for power consumption is: Power (watts) = Current (amps) x Voltage.

Rearranging, you get Current = Power / Voltage. Current = 14 watts/12 volts or 1.167 amps.

You need to know how much energy is stored in the battery to estimate out how long it will last. If the battery says it will last X hours when using Y amps, then you could estimate the time. If not, then you might be able to hook up the TV and time how long the battery lasts.

Even that has problems, because it also depends on what you're watching and the settings on the TV. A darker screen uses less energy than when you turn up the brightness, turning up the sound uses more energy than muting the speakers, etc.

You could just run a test, set it up and turn it on. Time how long it will last.

Batteries are rated in ampere-hours.

Ampere-hour - Wikipedia, the free encyclopedia