Have a Hot Water Recirculating Pump?

If you have a hot water recirculating pump system already built into your home, you know how great it feels to get instant hot water wherever it’s needed, especially for your morning shower.

How A Whole House Hot Water Recirculating System Works

A whole house hot water recirculating system continuously circulates hot water throughout the pipes so that hot water is immediately available at all faucets, tubs, washers, dishwashers and showers. You need both a recirculating pump and a loop piping system to work with your hot water heater. The pump is attached to your water heater. And the loop piping system begins and ends at your water heater.

Hot Water Recirculation Designed Into Homes

If your home was built with a hot water recirculating system, it looks something like this diagram. You’ll notice the dedicated “loop” piping configuration. Every water appliance branches off the main hot water pipe and then loops back to the water heater. That’s what enables each faucet, shower, washer and dishwasher to get immediate hot water.

If it was designed well from the beginning, you’re in luck! Many whole house recirculating pumps work great for twenty years or more!

diagram of loop system for hot water recirculation pump

Need the Pump or Piping Repaired or Replaced?

But if you have a problem with it, we’re here for you. Call us if you need the pump or piping repaired or replaced.

Tankless Water Heaters Will Work on a Hot Water Circulation System — With a Caveat

Tankless water heaters, also called “on demand” water heaters, do not actually supply instantaneous hot water. They heat water on demand but then the hot water needs to move through the hot water line to reach tap, dishwasher or shower. And that takes time.

And yes, you can use a tankless water heater in a hot water recirculation system. However, circulation systems are much more effective with tank-type water heaters.

Here’s why: A tankless water heater is triggered by a thermostat. It turns on when the temperature reaches a certain point and then turn off after a 15° rise in temperature.

As an example: When you start taking a shower, the water is 110°. That’s just before the circulation pump would turn on. However, the tankless water heater is set at 120. So as you’re showering you will notice a 10° rise in temperature once the newly heated water reaches the shower head.

Because of this, one of our clients actually had us remove the tankless water heater we had just installed and replace it with a tank-style water heater.

Find the basics of conventional tank-style or tankless water heater here. We’re happy to help you determine which will be best for your specific needs, particularly if you’re considering a hot water recirculating system.

Main Benefits to Hot Water Recirculating Pump System

Once we install a hot water recirculating system, water continually circulates through your plumbing and loops back to the water heater. So you get instant water at each water appliance, sink, tub and shower.

That leads, of course, to the main reasons why folks consider a hot water recirculating system. Here are top reasons:

#1 Reason to Install Hot Water Recirculating System: Instant Hot Water in the Morning Shower

  1. Convenience of instant hot water, especially in the morning shower
  2. Save water. Otherwise, you waste water that goes down the drain.
  3. Washers and dishwashers work most effectively when they call for the hottest water

Does a Hot Water Recirculating System Save Money?

It usually saves a little money. But cost-saving is not usually the main reason to consider a recirculating pump and system.

It definitely saves water. And in our area, water is one of our most precious resources. As water rates continue to increase, of course, you save more money.

However, while you save money on water, you pay a little more on energy. There are energy costs for running the pump and costs due to heat loss within the pipes. Some estimate the pump’s energy comparable to keeping a light bulb burning.

If you really want to get into the nitty gritty details to calculate the cost of running a hot water circulation system, you will find formulas for energy costs on the American Council for Energy Efficient Economy’s website. Their 2015 “Hot Water Forum” presented a paper comparing continuous, intermittent and on-demand button systems.

The paper concludes the most energy efficient pumps are ones with remote on-demand buttons. You put the buttons in bathrooms and kitchens and push them a few minutes before you need hot water. That triggers the pump to start recirculating hot water.

But if your family often needs hot water throughout the day, the remote buttons may not save much. That’s because the system still needs to push water out that’s cooled down between whenever the circulator pump kicks on. And not all family members remember to push the remote button before stepping into the shower.

You can also plug in a continuous running type pump into a timer. Set the timer so the pump turns off at night when you don’t need immediate hot water.

We Install Recirculating Pumps and Loop Piping System Solutions

If your home was not built with a hot water recirculation system up front, we can do it for you now. The pump itself, is fairly simple. However, there is no dedicated recirculating loop piping system so we need to create one.

Two Ways to “Loop” the Pipe Without a Dedicated Hot Water Piping System

#1 Recommendation: If you have a single story home, we run a new return line from the furthest fixture back to the water heater to create the loop and insulate it. In the drawing above, the furthest fixture away from the water heater would be bathroom #2 sink.

For option #2, we will go underneath the sink ( in the example above of Bathroom 2) and install valves, thermostat and pipes to the cold water line as the return line in the loop.

#2 Option: If option #1 is not possible, we use the cold line as a return line with a thermostat which prevents the water returning from getting too hot. There are two disadvantages to this option. The first is that if the plumbing is underground then it’s impossible to insulate the pipes. This causes quite a bit of heat loss and makes the system very inefficient . The second disadvantage is that when you turn on the cold water you’re going to have warm water come out of the cold side until the warm water is pushed out of the cold side of the system.

Not an Easy DIY Project

Regardless of what other websites may say, installing a recirculating hot water system yourself is not an easy task. In addition to the recirculating pump, you need to know where and how to install a variety of valves for a loop to work efficiently.

If you install pipes and valves incorrectly, your hot water can suddenly become TOO hot or drop too low.

Here are just a few examples of concerns :

  • To work properly, all control valves need enough flow. So make sure your recirculation pump is correctly sized.
  • A thermostatic mixing valve that does not close off completely on inlet ports can cause temperatures that are too high or too low.
  • A return valve regulates the amount of water going back to the cold inlet of the mixing valve. And a bypass valve controls the amount of water recirculating back to the hot water tank. Too much water returning to the hot water tank causes the water temperature to suddenly rise. Likewise, too little water going back to the hot water tank causes the temperature to become too low.

Basic Steps: How to Install a Recirculating Pump System

Remember, safety first! You’ll be working with electricity and hot water. Again, it’s best to call us to do this work. These steps will just touch on the basics.

  1. Shut off the water to the water heater.
  2. Drain the hot water out of the tank.
  3. Use a pipe wrench to remove the flex-hose pipe that supplies water to the tank.
  4. Attach the pump. If it comes with a rubber gasket on the female side, use it. Otherwise, use plumbers’ tape on the threads. Securely screw the pump into position, making sure any readouts, timers and gauges are easily accessible.
  5. Reattach the water supply line and screw the flex-hose pipe into the other port of the pump.
  6. On the furthest sink from the water tank (such as Bathroom #2 in our example), shut off the hot and cold water using the faucet’s shut-off valves. (You may want to first turn off the home’s main water shut off valve and check to make sure the faucet’s shut-off valve work without breaking off. Read “Find Your Home’s Main Water Shut Off Valve“.)
  7. Disconnect both the hot and cold supply lines from the shut-off valves and remove them. Be sure to keep a bowl and towel nearby to collect any residual water.
  8. Connect a check valve and position it to the hot and cold supply lines above the shut-off valves.
  9. Connect the supply lines to the sink and reattach the hot and cold lines onto their outlets. (Usually hot is on the left)
  10. Mount the check valve on the wall under the sink.
  11. Turn on the water and open the shut-off valves to the sink supply lines.
  12. Open the shut-off valve at the water heater.
  13. Open the cold and hot lines at the sink that has the check valve.
  14. Test for leaks by opening the faucet at the sink. Water should flow after air leaves the lines. After water starts flowing from the tap, check all the connections and supply lines for leaks. No leaks? Congratulations!

Sounds simple and straightforward … at first. But it can be and usually is much more involved than it sounds.

We Install the Right Pump, Valves & Piping for Your Home

We’ll install the best pump at the right size and flow rate for your home’s needs and pipe length. Sometimes DIYers or inexperienced plumbers install pumps that are too small or too large for the needs of the home.

When the pump is too small, it struggles, working too hard and soon gives out. If it’s too large, circulating water doesn’t have the chance to cool down and can’t always remain at a constant temperature. To determine the pump’s horsepower, we take into account the distance the water travels through the pipes and the location of the furthest faucet.

We also take gravity into account when choosing the most efficient pump. We can use a small horsepower pump if there is a gravity feed. Likewise, flow rate is a factor. We look at the size and type of plumbing in your home. The pump needs to push water through your pipes at the temperature and volume you want.

We Do it Right, at the Best Price, and Guarantee Your Satisfaction

You want it done right the first time and so do we. Our reputation depends on it. Our customers rate us five stars. We’ve earned it from them. We’ll do our best to earn it from you. We guarantee your satisfaction. And we guarantee our workmanship for TEN years.

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