I hear a loud popping sound mostly after one of the rinse cycles on my washing machine but more recently periodically I hear this sound without the machine running.
I had heard the tank needs to be cleaned from sediment. Any one know what is causing this?
Just a guess. There could be a layer of sediment (like sand) at the bottom of the tank and every once in awhile a pocket of steam develops down there and makes a popping sound as it breaks through the layer of sediment and commingles with (and is absorbed into) the rest of the water.
The hotter temperature down at the bottom of the tank (gas and oil models), insulated from the rest of the water by the sediment, could result in the layer of porcelain or glass inside the tank becoming cracked, shortening the life of the tank. Thus you are advised to drain a few gallons of water twice a year to get the sediment out.
The good conscientious technician or serviceperson will carry extra oils and lubricants in case the new pump did not come with oil or the oil was accidentally spilled, so the service call can be completed without an extra visit.