Hot Water Recirculation Pump Installation & Repair
Tired of waiting for hot water? A recirculation pump brings it to the faucet in seconds. We install, repair and replace them.
Updated October 2026 · By the Hot Water Heater Factory team
What does a hot water recirculation pump do?
It brings hot water to your fixtures before you turn on the tap. Without one, the water sitting in the pipes has cooled off, so you run it down the drain until the hot water arrives. A recirculation pump moves that cooled water back to the water heater and replaces it with hot water, usually on a timer, a thermostat or a push button.
What types of recirculation systems are there?
There are three main types. Which one fits depends on how your house is plumbed and what kind of water heater you have.
| System | How it works | Best for |
|---|---|---|
| Dedicated return line | A separate pipe carries water from the farthest fixture back to the water heater, with a pump near the heater. | Homes built with a return line. The fastest and most even hot water. |
| Under-sink crossover valve | A pump at the water heater and a valve under the farthest sink send cooled water back through the cold line. | Existing homes with no return line. No new pipe needed. |
| Tankless with built-in recirculation | Some tankless water heaters have a recirculation pump built in and work with a return line or a crossover valve. | Homes getting a new tankless water heater. |
How is a recirculation pump controlled?
- Timer: runs during the hours you use hot water, such as mornings and evenings.
- Thermostat: runs until the water in the line is warm, then shuts off.
- On demand: runs only when you press a button or a sensor detects you, then shuts off. Uses the least energy.
Is a recirculation pump worth it?
For most homes with a long wait for hot water, yes. You get hot water at the far bathroom almost right away and stop running gallons down the drain each day. The trade-off is a small amount of electricity for the pump and some heat lost from the pipes, which a timer or on-demand control keeps low.
What are the signs a recirculation pump has failed?
- The long wait for hot water is back
- The pump hums but the water doesn’t get warmer
- The pump doesn’t run at all, or its timer has stopped
- Warm water comes out of the cold tap (a crossover valve stuck open)
- Noise, rattling or a leak at the pump
Which recirculation pumps do you work on?
We install and service the common brands, including Grundfos, Taco, Watts, Bell & Gossett and Laing, plus the built-in pumps on tankless water heaters. Text us a photo of your pump’s label if you’re not sure what you have.
How long does installation take?
Many recirculation pump installs are done in a single visit. Adding a dedicated return line takes longer, and we’ll tell you up front what your house needs.
Waiting a long time is also a symptom on our water heater problems page. Getting a new tankless? See tankless water heaters.
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Recirculation pump installation near you:
Questions we hear a lot
How long should it take to get hot water at the faucet?
With a recirculation pump, a few seconds. Without one, it depends on how far the fixture is from the water heater; a minute or more at a far bathroom is common, which is when a recirculation pump makes sense.
Does a recirculation pump work with a tankless water heater?
Yes, with the right setup. Some tankless models have a pump built in, and others work with an external pump. The tankless unit needs a model and settings meant for recirculation.
Does a recirculation pump use a lot of electricity?
No. The pump itself is small. Most of the energy cost comes from heat lost in the pipes, which a timer or on-demand control keeps low.
Why is my cold water warm after a recirculation pump was installed?
With an under-sink crossover valve, a valve that sticks open can let hot water into the cold line. The valve can be cleaned or replaced, or the system can be changed to a different control.
Waiting for hot water? Text us now.
Send a photo of your water heater’s label and tell us what’s happening. A real person texts you back.