3130 S 6th Street, Lincoln, NE

Know Your Plumbing #2: Electric Water Heaters

You turn on the kitchen sink and wait for hot water to arrive, unless of course you have a re-circulation line. The majority of the time hot water will arrive and you won’t think twice about the water heater running in your mechanical room. However, what happens when the water stays cold? It will be time to investigate the reason why, and the first thing you will check is that water heater.

When you inspect your electric water heater, knowing what you are looking at is half of the battle. Any extra information that you can provide a plumbing service technician will save you both time and money. A description of the parts and features of an electric water heater are listed below.

Electric Water Heater Features

In the diagram shown you will see our typical electric water heater installation. The specific features of the electric water heater have been highlighted and match the descriptions to the left.

  • A: Water Shut-Off Valves – These valves are typically located immediately above the hot and cold water ports on your water heater. They can be used to shut down the water supply to your water heater, or to isolate the hot water in case of an emergency. If your water heater is ever leaking these valves can be closed to prevent further damage.
  • B: Electrical Disconnect Box – This electrical disconnect box should be located within arms reach of your water heater. Depending on the age of your home this box may not appear exactly as it does in the picture on the right.

Note: We do not recommend touching electrical components under any circumstances.

  • C: Temperature and Pressure Relief Valve (T&P) – This valve is designed to “open” in the event that the temperature or pressure in your water heater tank becomes to high. Typically these valves are piped down to the floor near a floor drain to allow the safe drainage of any blow-off that may occur. If you ever suspect that the T&P valve on your water heater is malfunctioning we recommend calling a licensed plumber in your area to diagnose the problem.
  • D: Temperature Settings – On most electric water heaters the temperature dials – to set water temperature – can be found behind these covers. Depending on the size of your water heater it may have two temperature dials, one for each element (as pictured to the right). If you believe your water may be to hot or cold please feel free to give us a call as we have the proper tools to diagnose your water temperature and make adjustments to the temperature settings.

Note: In no case should you turn your water heater temperature past 120 degrees F, as scalding can result.

  • E: Water Heater Drain (Boiler Drain)  – The boiler drain is used to drain down the water stored inside of the water heater. Typically a plumber will hook up a hose to the boiler drain and drain the water heater into the nearest floor drain. This allows them to “lighten up” the water heater for easy removal. In some cases this boiler drain will be extended and a fitting will be installed to tie in a re-circulation line, detailed below.
  • F: Re-circulation Line & Valve – Although a re-circulation line is not present on all water heater installations it is becoming a more common occurrence. In the picture to the right the re-circulation line is tied in to the boiler drain outlet, allowing water to continuously circulate through the water heater and back into the hot water pipes. On all re-circulation lines there should be a check-valve and a shut-off valve to allow for easy isolation of the line, in some cases there may also be a re-circulation pump installed to help move the hot water over long distances.

We always recommend calling a professional plumber to diagnose any water heater issues. However, the intent of this article was to highlight the features of an electric water heater to help you understand how they operate so you know what you are looking at when the hot water is no longer hot.

If you have any questions regarding the electric water heater in your home or would like clarification regarding anything in this article please feel free to leave a comment below.