Feb 17, 2015

Recirculating Pumps Save Hot Water and Offer You a Better Bathroom Experience - Sustain U Water Saving Series

What is a Residential Recirculating Pump?

Laing Autocirc Undersink Instant Hot Water Circulating Pump


Circulating pumps are often used to circulate domestic hot water so that a faucet will provide hot water instantly upon demand, or (more conserving of energy) a short time after a user's request for hot water. In regions where water conservation issues are rising in importance with rapidly expanding and urbanizing populations local water authorities offer rebates to homeowners and builders that install a circulator pump to save water.

Why would you install a Recirculating Pump? How much will you save?

In typical one-way plumbing without a circulation pump, water is simply piped from the water heater through the pipes to the tap. Once the tap is shut off, the water remaining in the pipes cools producing the familiar wait for hot water the next time the tap is opened. By adding a circulator pump and constantly circulating a small amount of hot water through the pipes from the heater to the farthest fixture and back to the heater, the water in the pipes is always hot, and no water is wasted during the wait. The tradeoff is the energy wasted in operating the pump and the additional demand on the water heater to make up for the heat lost from the constantly hot pipes. 

We have a passion for turning the world Green but for many of you it's all about $ which keeps capitalism humming. So what's the breakeven on the purchase of this pump. As with many Green products it seems the
more folks affected by the item the quicker the break even. If you live by yourself then this pump will likely take you a while to get a cost benefit. If you are in a 3 or 4 bath house with 2 or 3 kids then the payback is likely to be on the order of 2 years at most and then it will be straight savings against your utility bill.;

Are There Different Types of Recirculating Pumps?

While the majority of these pumps mount nearest to the hot water heater and have no adjustable temperature capabilities, a significant reduction in energy can be achieved by utilizing a temperature adjustable thermostatically controlled circulation pump mounted at the last fixture on the loop.

Thermostatically controlled circulation pumps allow owners to choose the desired temperature of hot water to be maintained within the hot water pipes since most homes do not require 120 °F (49 °C) degree water instantly out of their taps. Thermostatically controlled circulation pumps cycle on and off to maintain a user's chosen temperature and consume less energy than a continuously operating pump. By installing a thermostatically controlled pump just after the farthest fixture on the loop, cyclic pumping maintains ready hot water up to the last fixture on the loop instead of wasting energy heating the piping from the last fixture to the water heater. Often installing a circulation pump at the farthest fixture on hot water circulation loop due to limited available space, cosmetics, noise restrictions or lack of available power. 

Recent advancements in hot water circulation technology allow for benefiting from temperature controlled pumping without having to install the pump at the last fixture on the hot water loop. These advanced hot water circulation systems utilize a water contacting temperature probe strategically installed at the last fixture on the loop to minimize the energy wasted heating lengthy return pipes. Thermal insulation applied to the pipes helps mitigate this second loss and minimize the amount of water that must be pumped to keep hot water constantly available.

Can I install the Pump Myself?

Below is a video on installing a Laing pump. It is pretty easy if you are handy although you will require a 120v AC plug near the pump to power it. If electricity scares you a bit you would want to call the plumber or electrician to put a plug in for you. A professional depending on region would probably charge up to $200 for the install.

Which is the Best Manufacturer to go with on these pumps?

There are a few major manufacturers of residential plumbing recirculating pumps-they are all good companies and make good product-the choice is often based on your own personal affinity for a given brand or what your installer chooses.

Laing Pump Thermotech division of Xylem Water is the manufacturer we generally offer at Conservastore.
Laing offers a pump whose advantage is that the pump is placed at the faucet farthest in the plumbing loop from the water heater. This seems to do a great job of learning the temp at the coldest point of the system and thereby maintaining a constant temp that is agreeable
This is Conservastore Part #01-0228 and Laing Model # e1-bcanrt1w-06 and part#LHB08100093 and formally model ACT-303-BTW

Schematic of  a Recirc Pump Working

Laing has other models that may fit your requirements better:

A newer model from Laing is designed for the ever growing offering of Instantaneous of Tankless water heaters. The Model # is ACT E10 and the Part # 6050E7000

Laing now also offers a pump that is installed at the water heater but communicates with the farthest faucet in the home wirelessly. No recirculation line is required and no power source under the farthest sink is needed. Suggested savings is 12k gallons of water per year.
The Model # is ACT-4 and the Part # 6050E4050

Other good manufacturers of recirculating pumps include (click on the manufacturer name to go to their website)




If you live in a standard residential home with 3 or 4 bedrooms and 2 or 3 baths the relatively inexpensive cost of a recirculating pump will really save you water and utility bill cost over your life in the home

Thanks to the following for the text that is the basis for this article: Wikipedia, Laing Thermotech division of Xylem

This is from our Sustain U series of articles that attempt to inform the lay public about different Green hard good items that can make lives easier and of course save resources and save money

Conservastore is your source for Water Saving -  Click here for our entire catalog

Here is the Conservastore offering of Recirculating Pumps for Residential Water Heating-Click Here

Laing Autocirc Undersink Instant Hot Water Circulating Pump

Laing ACT E10 Autocirc Tankless Water Heater Recirculating Pump


This blog was first written in Feb 2014 and revised in Feb 2015


  1. Well if the pumps are recirculating all the time the pump doesn't have to heat the water as much. I think that is a really smart design and it will save a lot of money. If there was only some way that the hot water could never run out, that would be great. Especially in the winter when you really need hot water. http://www.tasenergysavers.com.au/#!heat-pump-hot-water/c11vh

  2. Hey, I am so glad to know about this Residential Recirculating Pump! It is great equipment. I want to buy honda water pump and I wonder if Honda also provides these kinds of pumps!

  3. Anonymous3:56 AM

    This is a brilliant writing and very pleased to find this site. I couldn’t discover to much different information on your blog. I will surely be back again to look at some other important posts that you have in future.
    residential electrician

  4. I read that Post and got it fine and useful.
    hot water tank calgary

  5. For quite a long time, I needed to have the productivity of a tankless water radiator, yet I never knew how to get a warmer introduced in our home since it contained a recycling pump associated with the current tank radiator. tankless water heater reviews