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How to Calculate Your Water Heater's Recovery Time and Why It Matters

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Heater repair Dublin,OH

One issue with traditional tank-style water heaters is that you can quickly run out of hot water. When you use up all of the hot water in a traditional water heater, you will often need to wait anywhere from 30 minutes to two hours or more for the water in the tank to reheat. This is why many people opt to switch to tankless water heaters. Tankless systems heat on demand to provide an essentially limitless hot water supply.

The time it takes to heat a full tank of water is known as its recovery time. How long this takes depends mainly on the tank's size and whether the unit is gas or electric. Calculating your recovery time is important because it will tell you approximately how long you'll have to wait before you have hot water again. It can also help you identify when your water heater isn't working correctly.

Determining Your Water Heater's Recovery Time

Recovery times can vary from one water heater to the next. The only real way to determine your unit's recovery time is to wait until you've used up all of your hot water and then time it to see how long it takes before your water is fully hot again.

To get a more accurate estimate, you will want to wait at least 30 minutes before checking the temperature. You can then turn the tap on and let it run for about 20 seconds before using an instant-read kitchen thermometer to measure the water temperature. If the water temperature hasn't yet reached what your water heater is set to, shut the water back off and then measure the temperature again 15 minutes later. You can then continue checking the temperature every 15 minutes until it is finally at the right temperature.

This will give you a good idea of how long your normal recovery time is, which can help you know when your water heater stops working efficiently. A few different issues could suddenly cause the recovery time to be much longer. If you notice that the recovery time has increased, you should schedule an inspection to determine why your water heater isn't working as it should.

How Flushing Your Water Heater Can Help Prevent Longer Recovery Times

Sediment build-up inside a water heater tank is the number one cause of longer recovery times and other water heater issues. When water is heated, some of the dissolved calcium and magnesium ions it contained will solidify and settle at the bottom of the tank. Over time, this sediment layer can build up to the point where it interferes with the unit's ability to heat properly.

This is why you should always have your water heater flushed at least once a year, as this will help to remove all of the sediment. The sediment will build up more quickly due to the higher mineral concentration in the water. So, if your home has hard water, you may want to have your tank flushed every six months.

Sediment build-up can affect both gas and electric water heaters, but it does so in different ways due to the differences in how each type of unit heats. Gas water heaters have a large burner located underneath the tank and connected to an exhaust flue that rises up through the middle of the tank and out the top. The exhaust flue partially helps heat the water since there is still quite a bit of latent heat in the combustion gases as they rise through it. However, most heat comes directly from the burner underneath the tank.

The issue is that all of the sediment at the bottom of the tank basically acts like a layer of insulation that blocks much of the heat and can drastically increase the recovery time. Sediment build-up can also create hot spots that can weaken the tank and increase the chances of it leaking. If you've heard a water heater making loud banging or knocking noises, this is also caused by sediment being disturbed and colliding with the side of the tank.

Electric water heaters are different in that they don't only heat from the bottom. Instead, these units have two electric heating elements—one at the bottom of the tank and one in the upper half. The issue here is that the sediment can damage the lower heating element and cause it to not work as well or fail completely, both of which will lead to longer recovery times.

Flushing a water heater tank involves connecting a hose to the unit so it can first be drained. Before doing so, it is always essential to turn the unit off for at least a few hours so that the water can start to cool to prevent the risk of scalding. Once the unit is drained, the water supply is turned back on so the tank can then be flushed.

Flushing a water heater on your own could easily damage the drain valve and cause the unit to leak. The drain valve also often becomes repeatedly clogged during the flushing process and sometimes needs to be replaced before the unit can be flushed any further. Replacing a drain valve is obviously something you don't want to do on your own, which is why it is always best to enlist the help of a plumber whenever it comes time to have your water heater flushed.

Other Issues That Can Lead to Longer Recovery Times

Longer than normal recovery times with an electric water heater almost always indicate that one of the heating elements has an issue and either needs to be repaired or replaced. This could be due to sediment build-up or simply due to normal wear and tear as the unit ages.

If you have a gas water heater, longer than normal recovery times could be related to sediment or some issue with the unit's burners. The gas burner ports often become clogged with dust and debris over time. This can make it so that the gas never fully combusts and doesn't burn as hot. This means that the unit won't heat nearly as quickly, and your recovery time will be much longer. The best way to avoid this issue is with annual water heater maintenance, as the plumber will always inspect and clean the burners.

If you're experiencing long recovery times or any other water heater issues, the experts at Apex Plumbing, Heating, and Air Pros can quickly get to the bottom of the problem. We specialize in a full range of water heater services. We are always ready to assist with your repair, maintenance, or water heater replacement needs. We work on all brands and models of both tank-style and tankless water heaters and can also help with any of your other plumbing, sewer or HVAC needs. Give us a call today if you need to schedule a water heater inspection or any other service in the Columbus, OH area.