Broken dip tube
The dip tube sends cold water to the bottom of the tank. If it breaks, cold water mixes at the top and you get lukewarm water quickly. It's a cheap part to replace.
Sediment taking up space
Years of sediment can take up a third of the tank. Flushing restores capacity — if the sediment isn't already rock hard.
Failed lower element or thermostat
On electric heaters, a dead lower element means only the top portion of the tank is heated. The upper element keeps working, so you get some hot water, then it's gone.
Undersized heater
If your family has grown or you added a soaking tub, a 40-gallon tank simply can't keep up. Upgrading to a larger tank or a properly sized tankless water heater solves it permanently.
Need a plumber for this?
MGA Plumbing provides tankless water heater installation 24/7 in every Missouri city — Kansas City, St. Louis, Springfield, Columbia and hundreds more. Upfront pricing, same-day service. Call (888) 480-9811.