Instant Hot Water: Strategies to Speed up Hot Water Flow from your Tankless Water Heater

Many people are disappointed when they realize tankless heaters do not provide instant hot water. In some ways, there is a mixture of definitions between instantaneous and continuous hot water. When it comes to tankless water heaters, all that is required is hot water when you turn on the light. That doesn’t mean you shouldn’t wait for hot water. Depending on the distance between the heater and the tankless hot water, you may have to wait a while for the hot water to arrive.

In this article, I will tell you how to get hot water quickly when you have a hot water tank.

Why do tankless water heaters take so long to heat up?

Consider how tankless heaters work and compare them to tank systems.

In a tankless water heater, cold water enters the heater. This water can be very cold if you live in a cold climate. It takes time for the element to heat up. Water passes through the feature as it is heated, so the first water that reaches you is the cold water in the pipe, and then the soft water passes through the element before it cools down.

Once the water reaches the desired temperature, it remains there forever. An endless stream of hot water.

The tank system is always hot. This is one of the failures. When you turn off the water, the tank is now heating the freshwater that came into it, whether you like it or not. The water in the pipe stays hot until it cools down from sitting there. No one provides hot water directly, but the tank system usually gives you hot water quickly.

How to get hot water directly from a tankless water

A hot water heater usually takes 10-15 seconds to deliver hot water to any faucet or water source. But there are some things you can do to get instant hot water. Here are a few.

Point of Use Tankless Water Heater

One option for quickly getting hot water is a tankless water heater. These electric appliances usually fit under your sink or closet, which is ideal for homes without gas or propane lines.

However, remember that these units are not ideal if you want hot water for your home. Not only do they last about half as long as their gas counterparts, but their Btu output is lower.

Bosch Electric Mini-Tank Water Heater Tronic 3000 T 4
Bosch Tronic 3000 T4 Mini-Tank Electric Water Heater
  • CONVENIENT HOT WATER HEATER: 4 gallon point-of-use mini-tank fits under…
  • LONG LASTING QUALITY: This electric water heater is easy to maintain and…
  • INDEPENDENT INSTALLATION: 36-37″ cord plugs into a 120 volt outlet for…
  • FAST RECOVERY RATE: Eliminates long waits for hot water at your sink, get…
  • EASILY MOUNTED: Can be shelf, wall or floor mounted (bracket included);…

High-efficiency condensing hot water

Tankless water heating technology continues to improve, and you may need a more efficient one to get hot water faster. And that means hot water heating. Tankless water heaters are not only about 20% more efficient than tankless water heaters, but they also save space. The efficiency comes from the second heat, which allows for efficient use. If you want to heat hot water, be aware that these units are expensive. This may not be necessary, depending on your hot water needs. A hot water system is required.

A demand hot water system gives you hot water quickly but slower than a circulating system.

Demand Hot Water Systems

A demand hot water system gives you hot water quickly but slower than a circulating system.

When activated, a demand hot water system uses a pump connected to your water line that takes hot water from your boiler and moves cold water to your hard water line. This causes the water to heat up quickly.

The advantage of on-demand systems is that they can be installed in your home and save money, water and energy.

Recirculating Pumps for Instant Hot Water

Another way to get instant hot water for your tankless tank is to get a pump. The way they work is to create a loop between the heater and your plug. The heater controls the heat when the water cools and activates the heater to heat the water.

Once you turn on the tap, you have hot water. Hot water in the pipes always returns to heating when the water cools.

If you still need a tankless water heater and instant hot water, be sure to buy one with a pump. Some do not have the pump, but they are designed with the ability to add one.

Tankless Water Heaters with Recirculating Pumps

Not all tanks have this ability, so you must ensure you get the right model if this is important.

Here is a list of tankless water heaters with built-in pumps. These are your best options right away without a tank.

Rinnai Tankless Water Heater Takagi Tankless Water Heater Rheem Tankless Water Heater Stiebel Eltron Tankless Water Heater
Rinnai RU199iP Takagi T-H3M-DV-N Rheem Prestige High Efficiency 9 Stiebel Eltron Tankless Water Heater

What are the Options For a Recirculating Pump?

You have two options when it comes to setting up your recirculating pump.

Create a dedicated loop.

A plumber can install a piping system that creates a loop between your radiator and your fixture and back to the radiator.

The downside is that it is expensive to set up. You will pay the sailor his usual wages plus the amount he wants. The length of pipe you need depends on the distance from the heating element. A recirculation pump is installed directly on the hot water without a tank so you will need a source nearby.

Some homes have installed a dedicated loop, so it pays to check it, as you may already have it set up without needing it.

Under-sink comfort system

To avoid the expense of adding a loop of pipes to distribute hot water, you can install an underwater comfort system. In this case, there is a type of switch that connects the hot and cold water lines under your sink. As the water heats up, the water from the cold pipes returns to the hot water. When the pump turns on, hot water will be directly in the device as soon as you turn it on. It is low. Since you don’t have a dedicated loop, you can get cold water or wait for the water to cool in the unit. Which method is right for you depends on your budget.

You can install the comfort system yourself; most of them work without a tank, saving money. Creating a dedicated loop is expensive and something you can do with others. You will need a licensed plumber, and verifying that the pump is compatible with your tankless water heater will be important. Most reciprocating pumps are available with a timer, so they only run some day. You can set them to heat water on the tap when you are at home and often need hot water.

Recirculating Pumps, You Can Use With a Tankless Water Heater

Some recirculation pumps state that they are not for use with tankless heaters, while others state that they are.

The truth is that it depends more on the hot water tank than the pump. In the section above, I have listed water heaters’ requirements for recirculation pumps. If you haven’t already, check that out, then come back here. This is a tankless water heater that comes with a recirculation pump so that you can use any of the following pumps:

Rinnai Tankless Water Heater
Rinnai RU199iP
  • Original Design: Tankless hot water heater’s Circ-Logic technology offers…
  • Never Run Out of Hot Water with this Compact Tankless Gas Water Heater:…
  • Smart, Durable Design: Includes 12-, 5-, and 1-year residential guarantee…
  • Professional Installation Recommended: Visit the Find a Rinnai PRO page on…
  • Find Your Rinnai: See our product guides, manuals, energy guide, warranty…

Rheem Tankless Water Heater
Rheem Mid-Efficiency 8.4GPM Outdoor Installation
  • Hot water without the wait – or the waste
  • Low operating cost – High energy efficiency and water savings setting
  • Space Savings – Compact, space-saving design. Perfect for a tank…
  • Water & Gas Leak Detection will shut down unit and provide an error code
  • For use indoor only

FAQ About Tankless Heaters and Instant Hot Water

How long does it take for water to get hot with a tankless water heater?

If your fixture is next to your tankless water heater, the water will get hot in a few seconds. And point-of-use tankless heaters give you almost instant hot water since they are right under your sink. However, if your fixture is on the opposite end of a large house or a couple of floors up, expect hot water in up to a minute.

The thickness and material of the pipes is also a factor.

How fast does a tankless water heater take to heat the water?

It only takes 15 seconds for the water entering the heat exchanger to reach the set temperature. This depends on how high your temperature is set and how cold the water is as it enters. Generally, up to 15 seconds with cold water and high-temperature settings.

Also, if your tankless uses less than 140,000 BTUs, it may take a little longer to heat the water to the desired temperature.

What is the normal temperature setting for a tankless water heater?

Usually, people set their tankless to 120°F to 140°F. The best temperature is 110°F, however, so you don’t have to mix cold water when showering or washing your hands.

You’ll get higher Gallons Per Minute (GPM) by lowering the temperature. The downside is that your washing machine and dishwasher need the water to be hotter. Hence, people keep the temperature high.

Can a water heater booster help me get instant hot water?

Although water heater boosters are for tank systems, this is a fairly common question. But no, water heater boosters won’t give you instant hot water. A water heater booster is great for increasing the quantity of hot water available. Unfortunately, it does not help you get hot water faster.

Wrapping It Up

I hope this clears up the confusion about whether a tankless water heater provides instant hot water.

They are worth it, even considering you need a recirculating pump to get faster hot water.

No situation is 100% ideal, so you need to understand your needs and wants before making a hard and fast decision.