How To Install a Recirculating Pump On a Tankless Water Heater

How To Install a Recirculating Pump On a Tankless Water Heater

A hot water recirculating pump can offer instantaneous hot water for showers and faucets while the water heater heats up. If your bathroom and shower are not close to the water heater, you may need to run the shower for at least 30 seconds before the hot water from the heater arrives.

A recirculating pump regularly returns the water in the hot water line to the water heater, keeping it warm and ready for use. The most common design among these systems is the instant hot water recirculating system. So, how to install a recirculating pump for a Tankless Water Heater? Read on to learn the steps in detail.

What Is A Tankless Water Heater?

These are the on-demand or instantaneous water heaters, often known as tankless water heaters, which only heat water to the temperature required. They can save money because they do not have the same standby energy losses as storage water heaters.

Best Seller
13KW at 240 Volts with Patented Self Modulating Technology
EcoSmart ECO 11 Electric Tankless Water Heater

13KW at 240 Volts with Patented Self Modulating Technology

Best Seller
18 KW at 240 Volts with Patented Self Modulating Technology , 17 x 14 x 3.5
EcoSmart ECO 18 Electric Tankless Water Heater, 

18 KW at 240 Volts with Patented Self Modulating Technology , 17 x 14 x 3.5

Best Seller
Digital thermostat with LED display, precise temperature control, durable heating elements.
Rheem 18kW 240V Tankless Electric Water Heater

Digital thermostat with LED display, precise temperature control,

Best Seller
Tempra 24 Plus – Electric, On Demand Hot Water, Eco, White, 20.2
Stiebel Eltron Tankless Water Heater – Tempra 24 Plus – Electric

Tempra 24 Plus – Electric, On Demand Hot Water, Eco, White, 20.2

Best Seller
Rheem 8kW 240V Tankless Electric Water Heater
Rheem 8kW 240V Tankless Electric Water Heater

ON/OFF dial control, digital temperature display, self-modulating power


The Components Of A Recirculation System

A recirculation system is made up of three major components:

Water Heater And Pump

The tank and water heater can be connected or separated. For tankless water heaters, both external and internal recirculation pumps are offered. With the use of additional components, the external pump can be programmed for periods when water usage is excessive.

Methodology Of Recirculation

This problem can be approached in two ways. The first makes use of a specific return line for circulation. As a result, you will have three pipes in your home: hot, cold, and recirculation. If you live in a one-story home with easily accessible pipes, this is a fantastic alternative.

Control Gain During Running.

At times, recirculation can be controlled by a timer. Another alternative is to use an aquastat or thermostat to activate the pump while keeping the water temperature in the line constant.

Also check: Gas Water Heater Not Working: What Could Be Wrong?

Benefits Of A Recirculating Hot Water Pump

The fundamental advantage of installing a hot water recirculating pump is that it provides instant hot water. Homeowners, on the other hand, install them for a variety of reasons. These pumps have various benefits. Some of the major advantages of a hot water recirculation pump are as follows:

Less Water Loss

This is a huge benefit. Millions of gallons of water are wasted each year while waiting for hot water. Californians, in particular, recognize the importance of this resource. It’s more vital than ever to think about where our water is going and what we can do to keep it safe.

Lower Water Bills

A hot water recirculating pump heats your water faster while using less cold water. If you use less water, your water bill may decrease.

Consumption Of Energy

A high-efficiency hot water recirculation pump consumes roughly the same amount of energy as a 60-watt lightbulb.

Less Maintenance.

In contrast to many other household goods, recirculation pumps do not require maintenance. After installing it, you may begin using it.


The following tools should be obtained before beginning the procedure.

  • Pump recirculation kit
  • A pipe wrench
  • Screwdriver
  • Bucket and towel


The procedures for installing a recirculating pump

Turn Off The Power And Water

Check that both the tankless water heater and the power are switched off. No further water should be added to the water heater.

Locate A Suitable Installation Point

Choose an appropriate location for the pump that circulates water. The ideal approach to attach it is to the tankless water heater’s hot water supply line. Choose a location that allows simple access to the pump when it has to be repaired.

Install The Pump

Cut the pipe to stop the hot water flowing. By installing a check valve, you may stop water from leaking backward into the cold water line.

Verify that the fittings needed to connect the recirculation pump to the hot water supply line are in place. Verify that the direction of the hot water flow and the pump are the same.

Electrical Connection  (if required)

The directions that came with your recirculation pump should be followed when connecting it to an electrical outlet. A thermostat or timer is often wired to a separate circuit in order to do this.

Set The Thermostat

In the morning and evening, or anytime you know you’ll need hot water, program the pump to run. As there will always be hot water and less energy used, this is good for the environment.

Insulate Hot Water Pipes

By insulating your hot water pipes, you may reduce your utility expenses and prevent heat loss. By following these steps, you can save hot water that you can use immediately.


If you want to utilize the tankless water heater once again, turn on the water. You can check the system to make sure there are no leaks and that the recirculation pump is working properly.


  1. The timer will automatically switch off the hot water when it’s no longer needed.
  2. If this pump is not grounded correctly in compliance with the National Electrical Code and any other relevant local laws, it will not operate as intended.
  3. Opt for the fastest speed if your pump has many settings.


Installing a recirculation pump can provide instantaneous hot water with minimal energy use if your water heater is tankless. You should read and abide by all safety labels and instructions, even if the processes are straightforward. You may enjoy the comfort of having hot water whenever you need it and contribute to a more environmentally friendly home with the right equipment. Recirculating pumps help you save money on energy costs while simultaneously increasing system efficiency.


About Author

Gulzar Abid

Gulzar Abid

Gulzar Abid is a passionate entrepreneur with a thirst for knowledge and yearns to help empower people to initiate their journey of growth and success. Chief Executive Officer K2 Groups Chief Executive Officer K2 Heating & Air Conditioning

Recent Posts

The Best Basic Home Tools kits


Stay updated on HVAC insights. Subscribe now!