On traditional tank water heaters, recovery rate refers to the time it takes for the water in the unit’s tank to completely reheat. In simpler terms, it means how long you will need to wait to have hot water again after using up all of your hot water. Recovery rates can differ depending on the age and size of the unit as well as whether it runs on gas or electricity.

Your water heater’s recovery rate will almost always be slightly longer during the winter, as the water coming into the unit will be colder. However, your recovery rate should always remain fairly consistent. If it suddenly takes longer for the unit to reheat, you will want to have your water heater inspected. It most likely needs to be flushed or repaired. Today we’re going to discuss what the typical recovery rate should be for your water heater and also what issues can affect the unit and lead to a longer recovery rate.

Typical Recovery Rates for Gas and Electric Water Heaters

Gas water heaters heat quite more quickly than electric units. The average recovery rate for a gas water heater that works properly and is heating efficiently will usually be between 30 minutes and an hour. A 40-gallon gas unit should be able to completely reheat in around half an hour, whereas an 80-gallon unit will almost always take around an hour.

The recovery rates for electric water heaters are often nearly double that of gas units. This means you could wait anywhere from one to two hours for the unit to reheat after you’ve depleted your hot water supply.

It is important to understand that recovery rates only refer to situations where you’ve used up all of the hot water quickly. To understand why, it is necessary to look at how water heaters work and where the hot water comes from.

All tank water heaters have something known as a dip tube. This is a long pipe that extends from the cold-water inlet at the top of the unit down to near the bottom. Any time you use hot water, cold water then flows through the tube to the bottom of the tank to replace it. The hot water is always drawn out from the top of the tank. This is important as it prevents the cold water from mixing as much with the hot water and thus decreases the temperature.

If the unit wasn’t designed this way, your water would quickly become cooler after just a few minutes of showering. Because of this, the only time you water should start to get cold is if you use up almost all of the hot water in the tank in a fairly short period.

Recovery Rate vs. First-Hour Rating

When looking at any new tank water heater, you will see that it lists the recovery rate and a first-hour rating. First-hour rating is different as it tells you how many gallons of hot water you can use in an hour when the tank is completely full and the water is heated to the correct temperature.

If you live alone, the first-hour rating isn’t something you’ll need to be too concerned with since there will be very few times when you use a huge amount of hot water in a short time. However, it is definitely something to consider if you have a larger family or live with multiple people.

Any time you use hot water, the water heater will turn on to start heating the cold water that flows out of the dip tube. If you continue to use hot water time, the unit will obviously continue heating until the water reaches the set temperature. The fact that the unit continually heats whenever hot water is used means you can often use more gallons of hot water than the tank can actually store. This is what the first-hour rating refers to, as it shows how many gallons of hot water a unit can provide per hour.

Since they heat more quickly, gas water heaters typically have a higher first-hour rating than electric units. In some cases, the first-hour rating can be almost double the unit’s storage capacity. For instance, you can often find a 40-gallon gas unit that will have a first-hour rating of 70 to 80 gallons. This means that the unit should make it possible for three or four people to shower within an hour, as the average shower uses around 20 gallons.

First-hour rating is important to consider when choosing a new water heater. A unit with a higher rating will make it less likely that you’ll run out of hot water.

Issues That Can Lead to Increased Recovery Rates

If your water heater’s recovery rate is longer than normal, it indicates that something is preventing the unit from heating properly. On electric units, longer recovery rates almost always mean that one or both electric heating elements are worn out or beginning to fail.

Both the upper and lower heating elements can wear out due to age, but the bottom element can also stop working properly if there is too much sediment built up inside the tank. If the sediment layer builds to the point where it reaches the lower heating element, it can act as an insulator and prevent much of the heat from the element from being dispersed into the water.

A longer recovery rate on a gas water heater can be caused by either sediment buildup or some issue with the gas burner. One possibility is that the ports on the burner are dirty. This can limit how much gas flows out and, thus how much heat the burner produces. That being said, sediment buildup is the more common cause.

When a gas unit is running, the heat from the burner is transferred to a metal burner plate located inside the very bottom of the tank. The metal plate absorbs heat from the burner and then releases it into the water. The issue is that a thick sediment layer can insulate the burner plate and prevent the water from directly contacting it. This leads to the sediment absorbing much of the heat instead of being transferred to the water.

If there is lots of sediment in the tank, the unit will heat much more slowly and use more energy. This is precisely why you should always have any type of tank water heater drained and flushed at least once a year. This will help to clean out all of the sediment.

Anchor Plumbing Services can help if you’re experiencing issues with long recovery rates or other water heater problems. We service and repair all models and types of water heaters, and we also specialize in water heater installation and all other residential plumbing services for customers throughout the San Antonio area. For more information, contact us today.

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