I've had this water heater for at least ten years, recently water has begun leaking from the pressure relief valve line. Do I require a new hot water heater?

Not necessarily The pressure release valve could just be getting old. Flip the top and purge it a couple of times and see if it stops the leak I like to quick flip it. If it gets worse or doesn't stop a new one is in order. Look at the top of the pressure valve and check its pressure rating. Now check your water pressure coming in the house to make sure its not close to the pressure relief rating. ( just a safety balance> Turn off hot water heater and let it cool down. Shut the valves off and partially drain the heater. Unscrew old pressure relief valve and get new to match P.S.I. Put knew back in and use Teflon tape on new threads. Open valves. Fill up tank by opening a hot side of faucet upstairs to fill tank up shut off faucet. Check new pressure valve if OK Turn on heater
Heater leaks out of bottom rusted out.
Three basic problems with Heaters
"gas" Thermal couple goes bad not allowing to light up burner
Nipples In heater waterlines clog ( low or no water to fixtures)
Electric heating elements go bad ( Luke warm or no hot water)
Pressure Relief valve gets corroded inside the valve and leaks

Signed 21 boat

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