Are you trying to find a new water heater but want to know how to pick the best model for your needs? are you commonly running the end of warm water mid-shower and wonder what you have the right to do about it? Let’s check out how lengthy it really takes a water heater to warmth up.

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Water heaters play an essential role in each family — there is no them, we wouldn’t have actually hot water for daily life. However they no magic machines capable of moving an unlimited flow, and also how rapid they warmth up relies on many variables.

How long Does It take a Water Heater to warmth Up

When it comes to water heaters, there’s a huge variety of sizes, types, and fuel or power sources. Every one of these influence exactly how long that takes the water heater to warm up.


If you’re in search of a water heater with small to no wait time, a tankless is perfect. Tankless or on-demand water heaters, occupational as you need them. They don’t have actually a tank which means that the water enters upon demand receiving heat as it circulates (3).

However, there are different sizes available, and most room meant together a point-of-use unit. Through that said, the mean waiting time is less than a minute.

Factors That influence Heating Time

The supposed waiting time is just a general estimation. Water heaters are affected by various determinants that can influence how long they take it to warm up. Some are universal across the different types, whereby others are much more specific.

1. First Hour Rating

The an initial hour rating speak you the number of gallons the water heater can deliver within the very first hour. It suggests the capability of the water heater after ~ it has recovered a full tank to the wanted temperature (4).

A high an initial hour rating method a much shorter waiting time. The calculation number relies on fuel source, tank capacity, and the size of the heating facets or burners (5).

2. Size of Water Heater

The dimension of your water heater is one more factor that can slow under the heating time. As you experienced in our earlier examples, a larger tank dimension takes longer to warm up. This is simply due to the fact that there’s an ext water come heat.

Larger tanks will usually have 2 heating elements or a huge burner to speed up the heating time. Still, a smaller tank will heat up quicker.

With that said, the smaller sized tank will likely run out faster than the bigger tanks. Therefore although you’ll have actually hot water in much less time, you’ll most likely run the end after young tasks.

3. Inlet Water Temperature

The inlet water temperature, or temperature rise, is one more factor that can seriously affect the recovery time. Relying on where girlfriend live, the inlet water will certainly have various temperatures. That generally cooler up North 보다 what it is in the South.

When us say “temperature rise,” we describe the temperature contrast between the incoming water and also the preset temperature top top the boiler. The chillier the inlet water, the longer it takes to warmth up.

4. Fuel Type

As you witnessed in our previously examples, fuel form makes a huge difference in restore time. Gas water heaters space a lot faster when it involves heating water than their electrical cousins. This is since gas burners with a much higher temperature 보다 the electrical heating elements.

Why Is It unexpectedly Taking Longer?

Over time, her water heater will likely take longer to warm up. However if it happens prematurely, examine the following:

1. Sediment Buildup

The most most likely reason that your water heater is suddenly taking longer to warmth up is sediment buildup. This is a common issue developing over time together your unit ages. However if you have difficult inlet water or ignore maintenance, it could happen a small earlier.

Sediment buildup is when the minerals present in the water begins to work out on the within of the tank. It can occur also with soft water that’s short in minerals, yet this will usually take a small longer before ending up being noticeable.

Sediment buildup consists of dissolved minerals such as magnesium and also calcium. This sit top top the walls of the tank and also the heating aspects where they can seriously limit the tank’s capacity to warm water.

There room three main indications of a buildup:

The unit takes longer to heat up and you’ll operation out a lot much faster than before.Significantly higher energy bills.

The best means to settle this problem is through flushing the tank regularly. However if you have actually an electric unit, and the heating facets are damaged beyond repair, you need to replace them.

2. Demands Troubleshooting

If sediment buildup no the issue, it might just be that the heating facets or thermostat need troubleshooting. This is a relatively easy procedure for an electric unit, yet if you have a gas heater, you’ll need some experience. This is also why we recommend contacting a professional.

If your unit is electric, here’s a brief explanation on how to troubleshoot it:

Turn off the power: rotate the breaker come the “Off” position before you handle any kind of electrical components.Access the thermostat: eliminate the accessibility panel utilizing a screwdriver. Then pull out the insulation to reveal the upper thermostat.Adjust the temperature: use a flat-blade screwdriver and turn the arrow indicating the temperature. Shot decreasing the temperature a few degrees.Finish up: replace the insulation and accessibility panel. As soon as ready, turn on the breaker to restore your water heater.

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If the recovery time is still too slow, it could be the you have to replace the heater elements. Or, perhaps your water heater simply isn’t big enough for your warm water needs.