Hot water circulating and recirculating systems, sometimes called recirc pumps, are pumps and systems that bring you instant hot water and conserve water in doing so.
Hot water circulating systems are hot water systems that circulate hot water through the hot water piping so that obtaining hot water is nearly instantaneous. They are often referred to as re-circ, recirc, or recirculating pumps.
This area of the Chilipepper web site provides an explanation of how the various types of hot water circulating systems work complete with illustrations of hot water circulating systems and other basic plumbing layouts.
Types of recirc systems include continuously circulating, timer controlled, temperature controlled, demand type, and combinations of all of these.
Hot water circulating systems generally provide convenience and save water but at the same time can waste large amounts of energy and cost the home owner a great deal of money.
As an example lets see how much energy is lost from a typical recirculating system. For our example we will calculate the amount of energy lost from a 3/4 inch copper pipe 50 feet long representing the piping through a home, and a 1/2 inch copper pipe 50 feet long representing the return line back to the heater.
Let the ambient temperature be 70 degrees F, a hot water temperature of 140 degrees, a 75 watt circulating pump running full time, and lets assume the piping is insulated with 1/2 thick insulation. There are 8,760 hours in a year.
For the 3/4 inch pipe the heat lost from the pipe is 12.4 Btu/ft-hr., and for the 1/2 inch pipe the loss is 9.9 Btu/ft.-hr. Doing the math we find that the losses for this system total to 9,767,400 Btu/year. If the pipe is not insulated the losses come to a whopping 37,492,800 Btu/year.
Figuring the energy required to run the pump gives us 657kWhr/year.
Gas and electric rates vary widely, but assuming 50 cents a therm (100,000 Btu) and 10 cents/kWh, it would cost $114.53 per year to operate. With the bare pipe version it would cost $253.16 per year to operate.
Maximum efficiency is obtained when the plumbing is designed for the circulating system, but in many cases a home owner wishes to add the recirc system to a plumbing system that already exists.
The following pages describe the various circulating systems and pumps in detail, how they operate, and the pros and cons associated with them.
Tuesday, January 12, 2010
saving water
It isn't easy to talk about the need to save water when storms cause creeks to spill their banks, fill reservoirs beyond capacity and the Salt River to flow through Phoenix for the first time in nearly seven years.
But don't let the weather fool you. Think of it as a real-life lesson about why water conservation is a timelier topic now than ever for Arizonans. The late-December storm didn't end the drought, nor will the next one. Arizona needs several years of above-normal conditions to recover. And most of that water running down the Salt River is lost.
This temporary abundance of water is really just another contradiction. We live in a desert, where droughts are common, yet we plant lush lawns and grow thirsty crops. Our population is growing in areas where our water supply is not. So we build dams and canals to import water in order to keep it cheap and fuel more growth.
Conservation should come naturally. Yet in most of Arizona, it doesn't. The urge to conserve seems to fade with the latest rain shower.
In the end, conserving water has little to do with drought or floods and everything to do with protecting a finite resource. It is not about making sacrifices. It's about eliminating waste. It's about saving our community's lifeblood for tomorrow.
Conserving water is something we do because we're responsible desert dwellers.
But don't let the weather fool you. Think of it as a real-life lesson about why water conservation is a timelier topic now than ever for Arizonans. The late-December storm didn't end the drought, nor will the next one. Arizona needs several years of above-normal conditions to recover. And most of that water running down the Salt River is lost.
This temporary abundance of water is really just another contradiction. We live in a desert, where droughts are common, yet we plant lush lawns and grow thirsty crops. Our population is growing in areas where our water supply is not. So we build dams and canals to import water in order to keep it cheap and fuel more growth.
Conservation should come naturally. Yet in most of Arizona, it doesn't. The urge to conserve seems to fade with the latest rain shower.
In the end, conserving water has little to do with drought or floods and everything to do with protecting a finite resource. It is not about making sacrifices. It's about eliminating waste. It's about saving our community's lifeblood for tomorrow.
Conserving water is something we do because we're responsible desert dwellers.
save water
Twenty-six-year old Shalini, a resident of a Mumbai [ Images ] suburb, bathes with three or more buckets of hot water on an average every day.
Rachel Pereira, a resident of the same suburb, laments the shortage of water in her household for the last month: "I have written to the municipality. The situation has not improved. In the last few days, we have had to visit friends or relatives to take a bath!"
WaterSuch is the current paradox.
In fact, a new study conducted in seven cities found that household activities -- washing clothes, bathing and washing of utensils -- result in maximum water wastage.
This, even as 65 per cent of the households face water deficiency.
The study, conducted by the Tata Institute of Social Sciences, was based on the water consumption pattern of households across Mumbai, Ahmedabad [ Images ], Hyderabad, Madurai [ Images ], Delhi [ Images ], Kanpur and Kolkata [ Images ].
Some more facts
i. Kolkata households consume the maximum water at an average of 445.5 litres per household.
ii. Madurai households consume the minimum water, with an average of 370.9 litres per household.
iii. Wastage is highest in washing clothes (83 per cent). It is followed by bathing (56 per cent) and washing utensils (49 per cent).
iv. Water usage for bathing and washing clothes contributed to about 28 per cent and 19 per cent of total consumption respectively.
v. The total average water consumption per household per day is 408.6 litres.
vi. The total average consumption of water per head per day is 91.6 litres.
The solutions
TISS faculty (urban studies unit) Dr Abdul Shaban says:
i. Use a bucket of water to bathe instead of the shower.
ii. Use low sud detergents which consume less water to wash clothes.
iii. Consider recycling the bath water for gardening.
Says Dr Shaban, "The need of the hour is to increase awareness on the conservation of water and a collective conviction from our countrymen to internalise this social cause."
As water consumerism reigns supreme, it is up to every one of us to take responsibility and use water with discretion.
Use water effectively. Here's how
Ganesh S Nochur, an environmentalist and former campaign director of Greenpeace, has some simple but effective tips to share about inculcating good water usage habits in your lifestyle.
1. Though the shower may be more fashionable and convenient, bathing with a bucket is truly a great way to save water.
With a shower, you lose count of how much water you are using. Besides, the new swanky showers spew out at least 40 to 60 litres a minute!
In comparison, one bucket holds between 15 and 20 litres of water. Thus, you can control the amount of water you usee.
2. Give your plants some extra nourishment by recycling the water you use to wash your your vegetables, fruits, rice, dal and other organic food items.
Of course, make sure there is no detergent used. These could be harmful for your potted babies.
3. The flush tank in your toilet consumes a lot of water. In fact, more than is required to maintain regular standards of hygiene.
To control the amount of water being flushed out at one go, insert a bottle of mineral water into the tank, or a brick wrapped in plastic. This occupies the same volume of the actual water. Thus when refilling, less water will fill up. But there will still be enough to keep the pot clean.
4. Make sure none of the faucets in your house are leaking.
If you lose a drop of water every second, it amounts to approximately 10,000 litres of lost water in a year! Thus, repair all leaking faucets and make sure you close the ones that work properly, nice and tight.
According to the TISS survey, besides bathing, laundry is another area which counts for the highest water wastage.
Here are some suggestions on how to watch water usage while washing clothes:
i. Use full loads of laundry whenever possible.
ii. Use low sud detergents which will consume less water while washing clothes. This consumes only one bucket of water against three buckets of ordinary detergent wash.
iii. For hand laundering, put a stopper in the washtub during washing and rinsing. Don't let the faucet run.
Rachel Pereira, a resident of the same suburb, laments the shortage of water in her household for the last month: "I have written to the municipality. The situation has not improved. In the last few days, we have had to visit friends or relatives to take a bath!"
WaterSuch is the current paradox.
In fact, a new study conducted in seven cities found that household activities -- washing clothes, bathing and washing of utensils -- result in maximum water wastage.
This, even as 65 per cent of the households face water deficiency.
The study, conducted by the Tata Institute of Social Sciences, was based on the water consumption pattern of households across Mumbai, Ahmedabad [ Images ], Hyderabad, Madurai [ Images ], Delhi [ Images ], Kanpur and Kolkata [ Images ].
Some more facts
i. Kolkata households consume the maximum water at an average of 445.5 litres per household.
ii. Madurai households consume the minimum water, with an average of 370.9 litres per household.
iii. Wastage is highest in washing clothes (83 per cent). It is followed by bathing (56 per cent) and washing utensils (49 per cent).
iv. Water usage for bathing and washing clothes contributed to about 28 per cent and 19 per cent of total consumption respectively.
v. The total average water consumption per household per day is 408.6 litres.
vi. The total average consumption of water per head per day is 91.6 litres.
The solutions
TISS faculty (urban studies unit) Dr Abdul Shaban says:
i. Use a bucket of water to bathe instead of the shower.
ii. Use low sud detergents which consume less water to wash clothes.
iii. Consider recycling the bath water for gardening.
Says Dr Shaban, "The need of the hour is to increase awareness on the conservation of water and a collective conviction from our countrymen to internalise this social cause."
As water consumerism reigns supreme, it is up to every one of us to take responsibility and use water with discretion.
Use water effectively. Here's how
Ganesh S Nochur, an environmentalist and former campaign director of Greenpeace, has some simple but effective tips to share about inculcating good water usage habits in your lifestyle.
1. Though the shower may be more fashionable and convenient, bathing with a bucket is truly a great way to save water.
With a shower, you lose count of how much water you are using. Besides, the new swanky showers spew out at least 40 to 60 litres a minute!
In comparison, one bucket holds between 15 and 20 litres of water. Thus, you can control the amount of water you usee.
2. Give your plants some extra nourishment by recycling the water you use to wash your your vegetables, fruits, rice, dal and other organic food items.
Of course, make sure there is no detergent used. These could be harmful for your potted babies.
3. The flush tank in your toilet consumes a lot of water. In fact, more than is required to maintain regular standards of hygiene.
To control the amount of water being flushed out at one go, insert a bottle of mineral water into the tank, or a brick wrapped in plastic. This occupies the same volume of the actual water. Thus when refilling, less water will fill up. But there will still be enough to keep the pot clean.
4. Make sure none of the faucets in your house are leaking.
If you lose a drop of water every second, it amounts to approximately 10,000 litres of lost water in a year! Thus, repair all leaking faucets and make sure you close the ones that work properly, nice and tight.
According to the TISS survey, besides bathing, laundry is another area which counts for the highest water wastage.
Here are some suggestions on how to watch water usage while washing clothes:
i. Use full loads of laundry whenever possible.
ii. Use low sud detergents which will consume less water while washing clothes. This consumes only one bucket of water against three buckets of ordinary detergent wash.
iii. For hand laundering, put a stopper in the washtub during washing and rinsing. Don't let the faucet run.
Subscribe to:
Posts (Atom)