September 2016


Running out of hot water while you take a shower is a pretty common problem, and not to mention quite annoying :S. When this happens, our first impulse is to turn up the temperature valve only to find out that the problem is still there or the water becomes too hot to take a shower. In some cases, you might even consider buying a new water heater, which can be very costly. So, before you take any drastic measures, read on this post as we will investigate the causes and possible solutions to this matter.


In most cases water heaters will produce less hot water as they age and reach the end of their lifespan, which is usually after eight years and above of use. Sometimes hot water can run out while you shower due to other problems that are easy to identify and repair. The way you should fix the problem will depend on the type of water heater you have, although the causes of the problem are generally the same. There are basically two types, electric and gas powered water heaters (these include tankless, hybrid and tanked units). Common problems that occur in most types of water heaters include:

  • Malfunctioning Parts

A part in your water heater can wear out over time or a manufacturing fault can be the cause of not having enough hot water. A trained water heater technician can diagnose your water heater and pinpoint the root cause of your hot water woes. Parts can easily be replaced and once installed, your water heater will start to work efficiently again. Components that usually wear out and cause cold or lukewarm showers while drawing water from an electric or gas fired heater include:

a) Thermostat

The thermostat is the gas control valve on a gas or electric water heater. It can get damaged or broken and cause temperature regulation problems.

b) Heating Elements

Electric water heaters have heating elements, which can burn out and cause the heater to malfunction.

They are two heating elements in most electric water heaters. Each element has a thermostat. If the thermostats do not function, the elements will not heat up.

In most water heater configurations, the lower heating elements and thermostat are controlled by similar components on the upper section. When the upper element or thermostat does not function, you will not have any hot water at all. A non-functioning lower element or thermostat will result in not having enough hot water.

c) Relief Valve

The temperature-pressure relief valve on the water heater keeps too much pressure from building up in the boiler and can interfere with temperatures if it is faulty.

  • Sediment Build Up

Sediment build up in your water heater will reduce the amount of hot water that it can produce. Hard water can deposit mineral particles and debris inside the tank. As these sediments accumulate over time, they leave behind a thick and sometimes crusty coating along the interior walls of the tank. This coating can hamper the transfer of heat from the burner to the water in the tank. Deposits can break away then clog taps, pipes and the valve used to flush your water heater tank.

  • Capacity or Size of the Water Heater/ Tank

If your move from a place with a large water heater tank to one that is smaller, you will notice that your hot water runs out faster. This is because the smaller tank will hold less hot water than you were accustomed to using.

The most common tank size in use is 30-40 gallons, which is adequate for a family of four. If you use hot water for the dishwasher or washing machine, you will not be able to shower with hot water for long.

With a large commercial water heater, you can shower with hot water for a longer time and at the same time use other appliances such as dishwashers and washing machines. But, keep in mind that a larger tank will also lead to higher energy bills.

When it comes to tankless water heaters, problems of inadequate heating can occur if the system is not properly sized. The capacity of a tankless system is measured based on the amount of flow that the system can heat to a given temperature. Therefore, using too many appliances at the same time will cause colder water to run out of a hot shower appliance.

If you’re having problems with a tankless water heater, installing other heating units at points of use might resolve the problem. To avoid this issue altogether, make sure to choose a tankless water heating system that supports a flow rate and temperature rise that is ideal for your specific needs. Be sure to do some research or consult a professional to size your tanked or tankless water heater based on your home’s specific needs.

  • Leaking Water Heater Tank

A leaking water heater tank could indicate that your tank is corroded, a heating element gasket is worn out or other issues. Regardless of the cause, a leaking tank will reduce the efficiency of your heater.

  • Distance of the Tank from the Bathroom

Hot water can cool off in the pipes if it has to travel some distance before it reaches your shower. You could be living in a big house or apartment building, with the water heater tank on one end of the building and the bathroom on the other. When you turn on the shower, the hot water has to travel through the pipes and may cool by the time it gets to your bathroom shower head.

  • Hot Water Heater Dip Tube

The dip tube is a plastic tube attached to the cold water section of the water heater tank. It delivers incoming/cold water to the heating elements located at the bottom of the tank. This tube prevents cold water from mixing with water at the top of the tank which rises after being heated up. If it breaks or falls into the tank, then cold water will mix with hot water, cause it to cool and significantly make your water heater less efficient.

Some Possible Solutions 

Some of the problems detailed above can be rectified and will enable you to take a shower without running out of hot water. Most of the repairs are quite easy and perhaps you can do them yourself while other kind of procedures are more complex and will require a qualified water heater technician.

  • Test the Hot Water Heating Elements

You should check and see if one or both of the elements are working. All you need is an element tester [multi meter] and a voltage tester.

  • Adjust the Thermostats

Adjusting the thermostat will involve removing metal covers on the hot water tank. This is necessary in order to access the insulator, which has to be pushed aside or taken apart to expose the thermostats and elements. You may also have to remove a plastic cover to make the adjustments. The adjustments can be done with a screwdriver to the heat descriptions that may have the actual temperatures in numbers, letter designations [A,B,C] or words “Warm” or “Hot”. Set the temperature to the recommended 120 degrees as anything above can cause serious injuries when you use the shower.

  • Check for Properly Grounded Elements

Elements will not work unless they are properly grounded. Therefore, you need to inspect them to ensure that the grounding connection is in place. Replacing any faulty elements or thermostat is not difficult once you know what you are doing and have the right equipment.

  • Check the Simple Things

Check the circuit breaker to make sure it has not tripped and reset the thermostat if necessary.

  • Flush the Hot Water Heater Tank

It’s important to flush or drain the water heater tank to remove sediment build up so that your heating system can produce enough hot water and work efficiently. You can do this by first turning off the gas valve or electric power. Turn off the inlet valve that supplies water to the tank. Attach a hose to the drain valve on the bottom of the tank and direct the hose to a drain outdoors or a large bucket. Open the hot water tap or pressure relief valve to let in air so that water can drain. Before you open the drain valve, make sure that the end of the hose is at a lower level than the drain valve so that the flushed water flows freely.

  • Insulate Hot Water Pipes

You can insulate your water pipes with foam pipes insulation sleeves to avoid hot water cooling if it has to travel a long way from your water heater tank to the shower head.

  • Install a Tankless Water Heater At Distant Fixtures

A point of use tankless water heater could be the solution to all your hot water heater problems, especially if shower heads, faucets, and other fixtures are far from the main water heater tank. Unlike conventional hot water heaters, a tankless unit heats water through electric coils or gas burners when water flows through. Turning appliances or taps on or off will switch it on or off and thus save on power consumption.

  • Replace Faulty or Damaged Dip Tube

You will need to replace the dip tube if you notice broken pieces of plastic in your tap. The sounds of something moving in the water tank when the water is turned on could be pieces of the dip tube that have disintegrated and broken off.
The above tips should be very helpful to get your water heater working efficiently so that you can enjoy a hot water shower every time. Make sure you turn off all the electric power before you undertake any repairs or trouble shooting to avoid electric shocks. You should also ensure that the temperature of the water heater is low to avoid scalding from hot pipes or water in the tank.