If the temp & pressure valve is the thing running water, it can be replaced, they do fail. If it is running because the pressure is too high, or the water too hot, that needs to be corrected. If it is leaking from some unknown spot, it probably cannot be fixed, and you need a new heater.
How old is the heater?? The date is either clearly written on the model# sticker, or coded into the model #. If it is more than 10 yrs old, consider a new heater.
How old is the heater?? The date is either clearly written on the model# sticker, or coded into the model #. If it is more than 10 yrs old, consider a new heater.