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Why You Have Inconsistent Hot Water


Anticipating a nice hot shower is a wonderful way to start your day. It's a bummer, though, to climb into a nice shower only to have the water temperature start fluctuating between hot and cold. You frantically keep adjusting the knobs or lever and pretty soon, relaxation has turned into irritation.

Here are the likely causes for why this might be happening and what to do about it.

What Size is Your Water Heater?

The average residential water heater has anywhere from a 28 to a 50-gallon tank. Since showerheads vary greatly in output-from two to 14 gallons per minute-it's possible your tank size is insufficient.

Are Other Appliances Running?

It could be that demand on your water heater is too high for enough hot water to reach your shower. If the problem is a new one, it could be due to a recent change:

  • Have you upgraded to a larger, spa-like tub?
  • Did you install a new shower head with multiple sprayer heads or a higher flow rate?
  • Have you recently remodeled and added a new bathroom or installed a shower in what was previously a powder room?
  • Are there more people in the house using hot water appliances at the same time?

Finally, new large-capacity washing machines might also put extra demand on the water heater. The solution could be as simple as replacing your heater with a larger capacity model. Some newer versions have tanks as large as 100 gallons.

Do You Have a Gas Water Heater?

If so, the gas burner might be dirty or faulty. Make sure the gas flame at the burner is steadily burning with a bright blue flame. If it's yellow or irregular in color, it won't heat up the water in the tank as effectively. A plumber can service the gas burner for you so the gas can flow freely or replace it if it's cracked or corroded.

Are Your Valves Old?

Many older valves were not designed to handle the hot water usage of modern homes. Plus, the older they are, they can start to fail to properly control the water temperature. They also lack temperature balancing features which keep water temperatures consistent even when there are fluctuations within the plumbing itself.

Another fix is to switch to a thermostatic mixing valve which, like a balancing valve, blends hot and cold water. But these models actually sense the water temperature and directly control it for more precise temps.

Your home's water heater is a real workhorse appliance that labors around the clock. Every faucet depends on it as do appliances like dish and clothes washers. And just like any other hardworking appliance, a water heater can develop a variety of problems and maintenance issues.

If your water heater has suddenly stopped producing enough hot water, or is delivering inconsistent hot water to your shower, David Gray Plumbing can help. For more than 25 years, we've been serving the plumbing needs of the Jacksonville FL area, including repairing, maintaining, and replacing water heaters. To learn more about how your water heater works or to schedule a plumbing check-up, give us a call at (904) 605-8190 or contact us online today.