Toilet repair is usually an easy DIY project. Almost all standard toilets have a flapper. The flapper is the rubber ball which lifts to expose a drain when the toilet is flushed and rests back in place so the tank can fill with water. For a short time after the flapper is returned to the fill position, you will hear the toilet ‘running’ as the tank fills. Eventually this noise will stop and that is an indication that the tank is full and the flapper is functioning properly.
If the toilet continues to ‘run,’ it is an indication you may need a new flapper. By lifting the top of the toilet tank, you can see the condition of the flapper. Is it losing its color? It is worn around the edges? Does it close all the way when the chain releases the flapper? Be sure to check the edges on the rubber seal where the flapper rests in place. If you see that it is ill-fitting or worn away, or not flush with the surface, you will need to replace that, as well. Without a properly functioning seal, the new flapper is useless.
If you do not have the specific model number of your toilet, remove the clip from the chain to release the flapper and gently pull the sides away from the prongs which hold it in place, and take it with the hardware store. Most sizes are standard and, therefore, easily matched. Be very careful to purchase the correct size and fit. If you are having difficulty finding the proper fit, go to a shop which specializes in plumbing supplies specifically.
Putting the new flapper in is just the reverse of removing it; it is just that easy! This should solve the running sound. If it does not relieve the noise, you should call your plumber immediately. If a toilet continues to run, it can mean several different things need to be repaired.
You may need a new refill valve or a new float. A more serious situation is that you might possibly have a pressure valve that needs replacing. A licensed plumber is the perfect fit to evaluate what needs to be done.