Plumb Hot Water Recirc System Like a Pro: Easy Steps

Enjoy Instant Hot Water with a Recirculating System

Tired of waiting for what feels like an eternity for hot water to reach your faucet? A hot water recirculating system offers a solution, providing instant hot water at your fingertips and eliminating the frustrating wait.

These systems not only enhance convenience but also contribute to water conservation and, surprisingly, energy efficiency.

What is a Hot Water Recirculating System?

At its core, a hot water recirculating system is a plumbing innovation designed to minimize the delay in receiving hot water from your taps, showerheads, and other fixtures.

It works by continuously circulating hot water through your pipes, ensuring that hot water is always readily available. This eliminates the need to run the tap and waste water while waiting for the hot water to arrive.

Two Main Types of Systems

There are primarily two types of hot water recirculating systems:

• Dedicated Return Line Systems: These systems require a separate, dedicated pipe running from the furthest fixture back to the water heater.
• Under-Sink Systems: A more recent innovation, these systems utilize the cold water line as the return path, simplifying installation, especially in retrofit situations.

Purpose of This Guide

This article serves as a comprehensive guide to help you navigate the installation process of a hot water recirculating system like a professional.

We will provide step-by-step instructions and valuable insights to ensure a smooth and successful installation.

A Word of Caution

Before we proceed, it’s crucial to emphasize the importance of safety and compliance.

This guide is for informational purposes only. Always consult with a licensed plumber for complex installations or if you are unsure about any step. Adhere to all local plumbing codes.

Working with plumbing and electrical systems can be dangerous, and improper installation can lead to serious consequences. Your safety and the integrity of your plumbing system should always be your top priorities.

Understanding Hot Water Recirculating Systems: How They Work

Now that we’ve introduced the concept of instant hot water, it’s time to delve deeper into the mechanics that make it possible. Understanding how hot water recirculating systems operate is crucial for choosing the right system and ensuring a successful installation. These systems, at their core, are designed to combat the frustrating wait for hot water, but their methods differ significantly.

What is a Hot Water Recirculating System?

The fundamental principle behind a hot water recirculating system is quite simple: a pump continuously circulates water from the water heater through the hot water line, and then back to the water heater, creating a closed-loop system. This constant circulation ensures that hot water is always present in the pipes, near your faucets and showerheads.

When you turn on the hot water tap, you get hot water almost immediately, eliminating the cold water that would otherwise sit in the pipes and go down the drain. This is achieved by preventing water from stagnating within the pipes.

Types of Systems

The method of returning the water to the water heater is where the two primary types of systems diverge. Understanding these differences is key to selecting the best option for your home.

Dedicated Return Line System

A dedicated return line system is the more traditional approach. As the name suggests, this type of system requires a separate, dedicated return line of piping running from the furthest fixture in your home back to the water heater.

The pump circulates water through the hot water line, and the dedicated return line provides a direct pathway for the cooled water to return to the water heater to be reheated.

This system is typically more complex to install in existing homes, as it requires running a new pipe. However, it often provides the most efficient and reliable performance, especially in larger homes with long pipe runs.

Under-Sink System

The under-sink system offers a more streamlined installation, particularly for retrofit projects. Instead of requiring a dedicated return line, it cleverly utilizes the cold water line as the return path.

This is achieved using an under sink recirculation kit, which includes a valve installed under the sink furthest from the water heater.

The valve connects the hot and cold water lines, allowing the pump to circulate water through the hot water line and then back to the water heater via the cold water line. This eliminates the need for running a new pipe, making it a more convenient option for many homeowners.

Benefits of a Hot Water Recirculating System

Beyond the obvious convenience of instant hot water, these systems offer a range of benefits that make them a worthwhile investment.

Instant Hot Water

This is the primary advantage, eliminating the often lengthy wait time for hot water to arrive at your faucets and showerheads.

This saves you time and frustration, especially during busy mornings or when you need hot water quickly.

Water Conservation

By preventing the need to run the tap while waiting for hot water, these systems significantly reduce water waste.

The amount of water saved can add up over time, contributing to both environmental sustainability and lower water bills.

Energy Savings

While it may seem counterintuitive, hot water recirculating systems can also contribute to energy efficiency.

By using a timer or thermostat, you can schedule the system’s operation for only when it’s needed most, such as during morning and evening routines. This prevents the system from running continuously, minimizing energy consumption.

Planning and Preparation: Choosing the Right System for Your Home

Having grasped the fundamental principles and types of hot water recirculating systems, the next pivotal step involves meticulous planning and preparation. This stage is crucial for a successful installation and ensuring the chosen system effectively meets your household’s hot water needs. Careful assessment, selection, and procurement are the cornerstones of this phase.

Assessing Your Existing Plumbing

Before diving into system selection, conduct a thorough examination of your existing plumbing infrastructure. This assessment will dictate the feasibility of different system types and inform component choices.

First, meticulously map out your current plumbing configuration. Understand the layout of your hot and cold water lines. Note the materials used (copper, PEX, etc.) and any existing connections or potential obstructions.

Second, check for accessibility. Can you easily reach the pipes near your water heater and at the furthest fixture? Are there accessible electrical outlets nearby for powering the pump and any optional timers or thermostats? Limited accessibility may steer you towards a simpler installation method.

Finally, measure the distance. Accurately determine the length of the hot water line from your water heater to the furthest fixture. This measurement is crucial for selecting a pump with sufficient power to circulate water effectively throughout the system. Longer runs necessitate more powerful pumps.

Choosing the Right System and Components

The assessment of your existing plumbing will heavily influence the selection of the most appropriate recirculating system. Both dedicated return line and under-sink systems offer distinct advantages depending on the circumstances.

Dedicated Return Line Systems

Dedicated return line systems are often the preferred choice in new construction or during major renovations. They provide the most efficient and reliable recirculation, ensuring consistently hot water throughout the house.

However, this type of system requires the installation of an additional dedicated return pipe running from the furthest fixture back to the water heater. This can be a significant undertaking in existing homes, involving running new pipes through walls, floors, and ceilings. You’ll also need to account for the cost and labor associated with installing the necessary fittings.

Under-Sink Systems

Under-sink systems offer a more practical solution for retrofitting existing homes. These systems utilize the cold water line as the return path, eliminating the need for a dedicated return pipe.

The installation is generally less invasive and less expensive than a dedicated return line system. An under-sink recirculation kit typically includes a valve that connects the hot and cold water lines under the sink, allowing the pump to circulate water through the cold water line back to the water heater.

Selecting a Pump

The pump is the heart of any hot water recirculating system, and choosing the right one is paramount. The size and flow rate of the pump must be appropriately matched to the size of your home and the length of your plumbing runs.

A pump that is too small will struggle to circulate water effectively, resulting in slow hot water delivery. Conversely, an oversized pump can waste energy and potentially damage your plumbing. Consult with a plumbing professional or refer to manufacturer guidelines to determine the optimal pump size for your specific needs. Consider the pump’s wattage and energy consumption, especially if you plan to run the system frequently.

Timer and Thermostat Considerations

Integrating a timer and thermostat into your hot water recirculating system offers enhanced control and energy savings.

A timer allows you to schedule the operation of the pump, ensuring that it only runs during periods of high demand. For example, you can set the timer to activate the pump in the mornings before showers and in the evenings before dinner preparation.

A thermostat monitors the water temperature in the return line and only activates the pump when the temperature drops below a set point. This prevents the pump from running unnecessarily and wasting energy. A thermostat also helps to prevent the water from becoming too hot, which can be a safety concern.

Gathering Necessary Tools and Materials

Before commencing the installation, ensure you have all the necessary tools and materials on hand. This will streamline the process and minimize delays.

Essential Tools:

• Pipe cutter (for copper or PEX, depending on your plumbing)
• Pipe wrench
• Adjustable wrench
• Teflon tape
• Screwdriver set (Phillips and flathead)
• Drill with appropriate drill bits (for mounting the pump)
• Multimeter (for electrical testing)
• Level
• Measuring tape

Necessary Materials:

• Pipes (if installing a dedicated return line system)
• Fittings (couplings, elbows, tees, etc., as needed)
• Check valve (to prevent backflow)
• Pump
• Timer (optional)
• Thermostat (optional)
• Electrical wiring (rated for the pump’s voltage and amperage)
• Wire connectors
• Mounting hardware (screws, anchors, etc.)
• Under-sink recirculation kit (if installing an under-sink system)
• Plumbers putty
• Sandcloth
• Safety glasses and gloves

Installation Steps: Dedicated Return Line System

Having diligently planned and prepared, chosen the right system and gathered the necessary materials, it’s time to get hands-on with the installation process. This section provides a detailed, step-by-step guide for installing a dedicated return line hot water recirculating system.

Safety is paramount, so meticulous adherence to these instructions is crucial. Always remember to consult with a licensed plumber if you encounter any difficulties or uncertainties during the installation.

Step 1: Shut Off Water and Electricity

Before commencing any plumbing work, the most crucial safety precaution is to shut off the water and electricity supply.

First, locate the main water shut-off valve for your home and turn it off completely. This will prevent any accidental flooding during the installation. Then, drain the hot water pipes by opening the lowest hot water tap in the house.

Next, turn off the electricity to the water heater at the circuit breaker. This is essential to avoid any electrical hazards while working near the water heater and connecting the pump. Verify that the power is off using a non-contact voltage tester.

Step 2: Install the Pump

The recirculating pump is typically installed near the water heater. Locate a suitable mounting surface, ensuring it is accessible for future maintenance.

Follow the manufacturer’s instructions for mounting the pump securely. Most pumps come with brackets and screws for easy installation.

Once the pump is mounted, connect the inlet side of the pump to the hot water line exiting the water heater. You may need to cut the existing pipe and use appropriate fittings, such as couplings, to make the connection. Ensure all connections are tight and secure to prevent leaks.

Step 3: Connect the Return Line

The hallmark of a dedicated return line system is, of course, the dedicated return line. This line runs from the furthest fixture back to the water heater, creating a closed-loop circulation system.

Connect the outlet side of the pump to this dedicated return line using appropriate fittings. Again, ensure all connections are tight and secure.

An essential component in this setup is the check valve. Install a check valve on the return line, typically near the pump, to prevent backflow of cold water into the hot water line. The check valve ensures that water flows in one direction only, maintaining the efficiency of the recirculation system.

Step 4: Install the Timer and Thermostat (Optional)

While not mandatory, installing a timer and thermostat significantly enhances the energy efficiency and convenience of the system.

The timer allows you to schedule the recirculation pump to operate only during specific times of the day when hot water is needed, such as mornings and evenings.

The thermostat regulates the water temperature in the recirculation loop, preventing it from getting too hot and wasting energy.

Wire the timer and thermostat according to the manufacturer’s instructions, paying close attention to the wiring diagrams and safety precautions.

Step 5: Restore Water and Electricity

With the plumbing connections and electrical wiring complete, it’s time to restore the water and electricity supply.

Carefully turn the main water shut-off valve back on, slowly filling the pipes. Inspect all connections for leaks. Tighten any fittings as needed until the leaks are stopped.

After verifying there are no leaks, turn the electricity back on to the water heater and the pump at the circuit breaker.

Step 6: Test the System

The final step is to test the system and ensure it is functioning correctly.

Run the hot water at various fixtures throughout the house, especially the fixture furthest from the water heater. You should notice hot water arriving much faster than before.

Check for adequate pressure and flow rate at all fixtures. If the pressure is low, inspect the pump and pipes for any obstructions.

Monitor the system for a few days to ensure there are no leaks and that the hot water recirculation is working as expected. Adjust the timer and thermostat settings as needed to optimize performance and energy efficiency.

Installation Steps: Under-Sink System

For homeowners seeking a less invasive approach, or those with plumbing configurations that preclude a dedicated return line, the under-sink system presents a viable alternative for achieving near-instant hot water. This method cleverly utilizes the existing cold water line as the return path, simplifying the installation process considerably. However, despite its relative simplicity, careful attention to detail is still crucial for a successful and safe installation.

Preparation is Key

As with any plumbing project, safety remains the paramount concern. Before proceeding, ensure you have carefully reviewed the planning and preparation steps outlined earlier in this guide, including assessing your existing plumbing and gathering the necessary tools and materials. It’s also worth reiterating our standing caution: if you are not comfortable with any of these steps, consult a qualified plumber.

Step 1: Shut Off Water and Electricity

This step mirrors the initial precaution taken for the dedicated return line installation. Turn off the water supply to the water heater by closing the main water shut-off valve. Subsequently, relieve the pressure in the hot water lines by opening a hot water tap. Then, and perhaps most importantly, switch off the electrical supply to the water heater at the circuit breaker. Confirm the power is off using a non-contact voltage tester to prevent electrical shock. This is non-negotiable.

Step 2: Installing the Under-Sink Valve

The heart of the under-sink system lies in the specialized valve installed beneath the sink furthest from the water heater. This valve facilitates the transfer of cool water from the hot water line into the cold water line, effectively creating the recirculation loop.

1. Disconnecting the Existing Lines: Begin by disconnecting both the hot and cold water supply lines from the faucet under the designated sink. Have a bucket and towels handy, as there will likely be some residual water in the pipes.
2. Installing the Recirculation Valve: Carefully follow the manufacturer’s instructions included with your under sink recirculation kit. This usually involves attaching the valve to the existing faucet connections, ensuring a secure and leak-proof seal. Teflon tape is your friend here. Pay close attention to the direction of water flow indicated on the valve. Incorrect installation will render the system ineffective.

Step 3: Installing the Pump

Unlike the dedicated return line system, the pump installation for an under-sink system generally remains the same.

1. Pump Placement: Mount the pump near the water heater, adhering strictly to the manufacturer’s guidelines. The mounting location should be easily accessible for future maintenance and repairs.
2. Connecting to the Hot Water Line: Connect the inlet of the pump to the hot water line exiting the water heater, using appropriate fittings and ensuring a watertight seal. Again, refer to the manufacturer’s instructions for the specific connections required for your pump model.

Step 4: Wiring the Timer and Thermostat (Optional)

As with the dedicated return line system, a timer and thermostat can significantly enhance the energy efficiency of the under-sink system. These components allow you to schedule the recirculation pump to operate only during peak usage times, preventing unnecessary energy consumption.

1. Timer Wiring: Wire the timer according to the manufacturer’s instructions. This typically involves connecting the timer to a power source and then wiring the pump to the timer, so the timer can switch the pump on and off.
2. Thermostat Wiring: The thermostat allows you to set a desired water temperature for the recirculation loop. Wire the thermostat in series with the pump, so the pump only operates when the water temperature drops below the set point.
3. Always follow the manufacturer’s wiring diagrams precisely and consult a qualified electrician if you are unsure about any aspect of the electrical connections.

Step 5: Restore Water and Electricity

After completing the plumbing and electrical connections, carefully restore the water and electricity supply.

1. Water Supply: Slowly turn the main water shut-off valve back on, allowing the pipes to fill gradually. Thoroughly inspect all connections for leaks. Tighten any fittings as needed to eliminate leaks.
2. Electricity Supply: Turn the electricity back on to the water heater at the circuit breaker.

Step 6: Testing the System

The final step is to test the system to ensure it is functioning correctly.

1. Running Hot Water: Open the hot water tap at the sink where you installed the recirculation valve. You should notice hot water arriving much faster than before.
2. Checking for Pressure and Flow: Verify that the water pressure and flow rate are adequate. If the pressure is too low, check the pump size and ensure that there are no obstructions in the pipes.
3. Monitor the System: Keep a close eye on the system for the first few days to ensure there are no leaks or other issues.

Troubleshooting Common Issues with Hot Water Recirculating Systems

Even with meticulous installation, hot water recirculating systems, like any mechanical system, can encounter problems. A systematic approach to troubleshooting will help you identify the root cause and implement effective solutions, or at least, provide you with information to intelligently describe issues to your plumber. Here’s a guide to addressing some common issues.

No Hot Water

The frustration of installing a hot water recirculating system, only to still face cold showers, can be easily remedied.

The absence of hot water despite the system’s presence is often traced to a few key areas.

Electricity Supply: Begin by verifying that the pump is receiving power. Check the circuit breaker to ensure it hasn’t tripped. Use a non-contact voltage tester to confirm electricity is reaching the pump.

Check Valve Orientation: An improperly installed check valve can impede or completely block water flow. Ensure the check valve is oriented correctly, allowing water to flow away from the pump and towards the return line. Reverse it, if needed.

Timer and Thermostat Settings: If your system incorporates a timer or thermostat, confirm that they are programmed correctly. The timer should be set to operate during periods when hot water is needed, and the thermostat should be set to an appropriate temperature.

Consider seasonal changes may affect the thermostat settings, requiring adjustment.

Leaks

Water leaks, regardless of size, should be addressed promptly to prevent water damage and potential mold growth.

Tighten Fittings: The most common cause of leaks is loose fittings. Use a wrench to gently tighten all connections. Avoid over-tightening, as this can damage the fittings.

Replace Teflon Tape: If tightening the fittings doesn’t resolve the leak, remove the fitting, clean the threads, and reapply fresh Teflon tape. Wrap the tape clockwise around the threads several times before reassembling.

This creates a better seal.

Low Water Pressure

Reduced hot water pressure can diminish the benefits of your recirculating system.

Pump Size: An undersized pump may not be capable of providing sufficient pressure to all fixtures, especially in larger homes.

Consult the pump’s specifications and compare it to your home’s plumbing demands.

Upgrading to a larger pump might be necessary.

Pipes for Obstructions: Over time, sediment and mineral buildup can restrict water flow within the pipes. Flush the system to remove any debris. If the problem persists, consider consulting a plumber to inspect the pipes for more significant blockages.

Pump Noise

Excessive noise from the pump may indicate a problem.

Air in the System: Air trapped within the pump can cause it to operate noisily. Try bleeding the system to remove trapped air. Consult your pump’s manual for specific instructions.

Pump Impeller Obstruction: Debris can sometimes become lodged in the pump’s impeller. This can cause noise and reduce the pump’s efficiency. Shut off power and water and carefully disassemble the pump to clean the impeller.

Worn Bearings: Over time, the pump’s bearings can wear out, leading to increased noise. In this case, replacing the pump may be necessary.

Maintaining Your Recirculating System for Optimal Performance

A hot water recirculating system is a valuable investment, providing convenience and conserving water. However, to ensure its continued optimal performance and longevity, regular maintenance is essential. Neglecting maintenance can lead to decreased efficiency, costly repairs, or even system failure.

Regular Inspections: The First Line of Defense

Regular visual inspections are crucial for identifying potential problems early on. Make it a habit to check the pump and surrounding plumbing at least every few months.

Listen carefully for any unusual noises emanating from the pump during operation, such as grinding, rattling, or excessive humming. These sounds could indicate a worn-out motor, impeller issues, or other mechanical problems.

Carefully examine all fittings and connections for any signs of leaks. Even small drips can lead to significant water waste and potential water damage over time.

Address any leaks promptly by tightening fittings or replacing Teflon tape as needed.

Flushing the System: Removing Sediment Buildup

Over time, sediment and mineral deposits can accumulate within the pipes and components of your recirculating system, reducing its efficiency and potentially causing blockages. Periodic flushing helps to remove this buildup and maintain optimal flow.

The frequency of flushing depends on the water quality in your area. If you have hard water, you may need to flush the system more often.

Generally, flushing the system once a year is a good practice.

To flush the system, first, shut off the water heater and allow the water to cool.

Then, open all hot water taps in your home and let the water run until it runs clear. This will help to flush out any accumulated sediment.

You may also consider using a descaling solution designed for plumbing systems. Follow the manufacturer’s instructions carefully.

When to Call a Plumber: Recognizing the Limits of DIY

While some maintenance tasks can be performed by homeowners, it’s essential to recognize the limits of your DIY capabilities and know when to consult a licensed plumber.

If you encounter any complex issues, such as persistent leaks, electrical problems, or unusual pump behavior, it’s best to seek professional assistance.

Attempting to fix these problems yourself could potentially void the warranty or lead to further damage.

Additionally, consider scheduling regular professional maintenance checks every few years. A plumber can inspect the system thoroughly, identify any hidden problems, and perform necessary repairs or adjustments to ensure optimal performance.

Investing in regular maintenance will extend the lifespan of your hot water recirculating system and ensure years of reliable, efficient operation.

Alright, you’ve got the know-how! Now go out there and tackle that project of how to plumb hot water recirculating system like a boss. Happy plumbing!