Hot water runs out after 10 minutes? You may have an issue with a faulty thermostat or an element. It could also be a power issue.
The cause is most likely the bottom element in the electric hot water tank is worn out or needs to be replaced. This is typical if you have hot water for a short amount of time.
Hot Water Runs Out After 10 Minutes?
To understand why you’re running out of hot water within 10 minutes, you need to understand how a hot water tank works.
Every hot water tank has two elements. It has an element at the top of the tank and an element at the bottom of the tank.
Since heat rises the element at the top of the tank comes on first.
This element will stay on until it gets to the setpoint of the thermostat which is usually 140°F.
Once the top of the tank is satisfied it then switches over to the bottom element to hit the bottom half of the tank.
The same process continues with the bottom of the tank until the thermostat was satisfied and it reaches 140°.
The reason you could be running out of hot water within 10 minutes is because only the top element is doing the heating.
This means that you were still get hot water because the top half of the tank is hot but it runs out quickly because the bottom of the tank is still cool.
Why Does My Hot Water Run Out After 10 Minutes Not Being Used?
The same principle applies to the tank if it is not being used if it just sits without hot water being drawn from the tank.
Then it will only heat the top half of the element until it is satisfied.
If the bottom half of the element is burned out that it was simply not heat.
This can be a faulty thermostat issue or an element issue.
If the bottom element gives up then only the top of the element will work.
Additionally if you have a faulty thermostat with the top half of the element this could cause a heating problem as well.
How Long Does It Normally Take to Run Out?
Hot water should normally take about 20 minutes under normal circumstances to deplete.
This is assuming that you were using fully hot out of the tap.
If you mix it with cold then you can get up to 40 minutes of hot water or warm.
However if you have any condition less than this for the hot water runs out quicker than you have problems with the tank.
If you have luke warm water then this could be a sign of a thermostat problem as well.
If the thermostat is not working correctly then the tank will not reach its proper temperature.
This could also mean that you have a problem with the power in the tank only getting half the voltage as opposed to the full 240 V.
You can read more on this issue in some of our other articles here.
What Can I Do To Fix It Myself
Although we cannot legally tell you that you can fix this issue yourself because it involves electricity.
We need to tell you that you should hire a local electrician.
However we can describe to you how we would fix the issue. Firstly we will need to drain the tank.
This would be after we shut the power off. After we shut the power off to the tank then we know it’s safe for us to work on the tank.
We would start by disconnecting the wires to the element and taking a small multi metre on homes to check to see if we have an ohm reading.
If we do not get a ohm reading then we know that the element is gone.
We then unscrew the element from the tank.
Before we install the new element we are sure to clean up any rust around the hole going into the tank.
It’s also a good idea to use plumbers silicon around the rubber gasket of the element to make sure it gets a good seal.
When we refill the tank we open the pressure relief valve at the top of the tank until water spits out so we can sure that the tank is full.
This is done before we turn the power back on.
And there you have it that’s how we would change an element.
How Can I Drain The Tank
To drain the tank we simply shut the power off first.
This is usually located by a breaker or service disconnect next to the tank.
we then will hook a half inch garden hose to the bottom of the drain line of the tank to a nearby drain or outdoors if we need to.
We are always certain that we shut off the cold water line intake to the top of the tank before we open the drain.
This will prevent any cold or cold water trying to fill the tank back up.
Then simply open the drain valve and let the tank drain.
This can take anywhere from half hour to an hour depending on how fast the tank drains.
What Can I Do To Stop It In The Future?
We recommend to avoid this issue in the future to make sure that you have the quality water.
Sediment and build up in the bottom of your tank can be the culprit to causing the bottom element to burn out.
All of these factors will contribute to hot water runs out after 10 minutes.
In addition to that we also recommend that you get professional rated tank that has a longer lifespan than the average tank of 5 to 7 years.
Find out more what we recommend a professional rated tanks find out more here.