No Hot Water? DIY Troubleshooting Guide

No hot water? Running out of hot water in a busy household where back-to-back showers and dishwasher use may have drained the reserves is annoying, but short-lived. You simply wait for more water to heat back up. When the water stops heating altogether, it’s time to take action, starting with troubleshooting this often elusive plumbing problem.

Your home will either be equipped with a gas water furnace or an electric model. It’s important to know which kind you have because the potential problems will be different for each. Regardless of the type, always remember to follow safe electric and gas precautions when inspecting the tank.

Troubleshooting the Problem – Possible Causes for No Hot Water

Electric Water Heater

  • Circuit breaker/fuse box – Has a circuit breaker been tripped or a fuse blown? Is there power to the water heater?
  • Is the thermostat working properly?
  • Is the upper heating element still working? – A multimeter is a handy tool to diagnose this.
  •  Reset button – Extremely hot water can cause the button to trip prematurely

Gas Water Heater

  • Is the pilot light out? – If yes. Try relighting again by using a match or electric ignitor (available on newer models). WARNING – Permanently affixed to each water tank is a detailed set of instructions and safety precautions for lighting the pilot light. Make sure you read this information thoroughly.
  • Is the pilot hard to light with the ignitor? – The electric igniter switch may need to be replaced.
  • Does the pilot light continue to go out? – You may have a bad heater thermocouple.

IMPORTANT – Be sure you know where your main water shutoff valve is for any water-related emergency.

Unless the problem is obvious like a leak in your water tank, troubleshooting the cause for a lack of hot water may be time-consuming and in the case of gas water heaters, extremely dangerous. Your best bet is to call a licensed and certified plumber like Comfort Systems to help diagnose and fix your problem as soon as possible.