Reclaim waste water heat. - Page 2

kbhale · 04-11-10, 02:25 AM

Sorry, I don't have any data. All I do know is that the barrel is warmer after I take a shower. I plan to put a insulation blanket around the barrel to keep the heat in it and under it. Hopefully this will help increase and maintain the overall temp in the barrel for better pre heating.

My biggest problem was getting a good seal on the barrel. I did not put in a drain valve. Should have.

Mine is all plastic. Peeing in it won't hurt it. I don't at the present time see any reason to worry about build up. A dose of lye once a year for hair balls should do it.

If you can do it on the cheap go for it. It will save you some money over time.

I'm buying material now to build my second water tank. It will be used to provide hot water and help heat the home. Do plan to keep the barrel in front of the tank for pre heating domestic water.

osolemio · 05-20-10, 11:32 AM

I am using a waste water recovery heat exchanger called Power Pipe, from Renewability, and It works quite well so far. It does not store any water, just takes out a lot of heat from the drain water and preheats the cold water before it enters the heat buffer instant hot water system.

While taking a shower around 95F, the cold water in is around 40F, preheats to around 70F, so I am getting about half the heat back again.

We now have three water sources in the house:

Hot - the usual one
Warm - the new preheated water from cold
Cold - the usual one

What used to be "cold" in this house is now connected to "warm" instead, to make maximum use of the system. To cater for special needs, new tubes have been made specifically to get Cold water (no preheating) for bathroom cold water (sink only), kitchen sink, fridge ice cube water inlet and one special "cold tap". The rest is preheated now, including toilets, dishwasher and washing machine, but the toilet flushing and washing machine will eventually become fed by rainwater.

Since "warm" is also the feed for all the hot water, it is quite important that the heat exchanger allows as much flow as possible. The heat exchanger we have has four small tubes in parallel.

If you buy one of these devices, make sure it has sufficient flow capability to allow for your combined needs. If necessary, mount two of them and parallel the water.

Once installed, they just sit there and work in a passive way. No controllers, pumps or valves ... no maintenance!

Daox · 05-20-10, 12:51 PM

How long is the power pipe you are using?

osolemio · 05-21-10, 12:50 AM

Quote:

Originally Posted by Daox

How long is the power pipe you are using?

I got the 54 inch model, 4 inch diameter (as drainwater pipes here are usually 110 mm which is just over 4 inch). I asked about it at Renewability and I got a reply from the Swedish dealer, and they also have the regional dealership for Denmark. They do not have many versions in stock, so although I could have gotten a 60 inch model to fit here, I ended up with the 54 inch model.

AC_Hacker · 06-30-10, 07:08 PM

There's a Wiki on the subject HERE.

-AC_Hacker

AC_Hacker · 11-29-10, 11:42 AM

I came across a FAQ by a company called ReTherm that makes grey water heat recovery devices.

Q1. Does ReTherm have to be installed vertically? Can it be installed on the horizontal?
A1. Installing the ReTherm unit vertically is the only way to obtain the highest level of heat recovery. Having the unit installed horizontally will only deliver 1/5th of the heat recovery compared to the vertical install.

Q2. How much electrical power does ReTherm require?
A2. None. No electrical hook-up is needed. Our drain water heat exchangers do not require any electricity to recycle hot water heat.

Q3. How long does it take to complete a typical household installation?
A3. New Construction - Installing ReTherm as the home is being built requires 1-2 man hours. Retrofit - Installing ReTherm into an existing home typically requires 4-6 man hours.

Q4. Can ReTherm be used to collect the heat from my hot water baseboard radiator piping?
A4. No. The hot water that flows through the baseboards, radiators or through the in-floor heating pipes is never thrown away. It is a "closed-loop" pipe system that reuses the same water day after day, year after year.

Q5. Can ReTherm be installed as a do-it-yourself project in a home?
A5. Yes. The skills and knowledge required to properly install a ReTherm unit are basic. Many DIYers have completed their own ReTherm install.

Q6. Will ReTherm cause any problems for my private septic tank? Will it prevent it from working properly?
A6. No. Contrary to common perception septic tanks do not require any warm or hot water in order to function normally.

Q7. How long is a ReTherm unit expected to last?
A7. Since ReTherm units have no moving parts and are built entirely of durable copper the lifecycle is expected to be 40 years plus.

Q8. Will ReTherm be more effective if it is insulated?
A8. If the unit is installed in an area that is unheated or is normally less than room temperature then we recommend that the unit be insulated. However, if the unit is installed in an area that is maintained at room temperature insulating the unit is optional.

Q9. Is hard water a problem for ReTherm?
A9. No. Minerals in water can leave deposits when heated to high temperatures. Unlike boilers and other water heaters the temperature boost delivered by a ReTherm unit is not high enough to cause mineral build-ups on the surfaces of the unit.

Q10. Should the water pipe between the ReTherm unit and the water heater be insulated to prevent heat loss?
A10. Yes, this is recommended especially if the water lines are copper. If the water lines are plastic the heat loss from un-insulated pipes will be negligible since plastic is such a poor conductor of heat.

Q11. Can ReTherm heat all of my hot water?
A11. Although larger ReTherm units can recycle more than 60% of the heat from the shower they cannot replace the need for some type of "powered" water heater. ReTherm works with conventional "powered" water heaters. It cannot replace a powered water heater because it cannot heat water totally, it can only preheat water using the heat that is available from drain water.

05-20-10, 11:32 AM	#12
osolemio Hong Kong Join Date: May 2010 Location: Hong Kong Posts: 108 Thanks: 20 Thanked 17 Times in 13 Posts	I am using a waste water recovery heat exchanger called Power Pipe, from Renewability, and It works quite well so far. It does not store any water, just takes out a lot of heat from the drain water and preheats the cold water before it enters the heat buffer instant hot water system. While taking a shower around 95F, the cold water in is around 40F, preheats to around 70F, so I am getting about half the heat back again. We now have three water sources in the house: Hot - the usual one Warm - the new preheated water from cold Cold - the usual one What used to be "cold" in this house is now connected to "warm" instead, to make maximum use of the system. To cater for special needs, new tubes have been made specifically to get Cold water (no preheating) for bathroom cold water (sink only), kitchen sink, fridge ice cube water inlet and one special "cold tap". The rest is preheated now, including toilets, dishwasher and washing machine, but the toilet flushing and washing machine will eventually become fed by rainwater. Since "warm" is also the feed for all the hot water, it is quite important that the heat exchanger allows as much flow as possible. The heat exchanger we have has four small tubes in parallel. If you buy one of these devices, make sure it has sufficient flow capability to allow for your combined needs. If necessary, mount two of them and parallel the water. Once installed, they just sit there and work in a passive way. No controllers, pumps or valves ... no maintenance! __________________ Space heating/cooling and water heating by solar, Annual Geo Solar, drainwater heat recovery, Solar PV (to grid), rainwater recovery and more ... Installing all this in a house from 1980, Copenhagen, Denmark. Living in Hong Kong. Main goal: Developing "Diffuse Light Concentration" technology for solar thermal. Last edited by osolemio; 05-20-10 at 11:38 AM.. Reason: Adding information

05-20-10, 12:51 PM	#13
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	How long is the power pipe you are using? __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

06-30-10, 07:08 PM	#15
AC_Hacker Supreme EcoRenovator Join Date: Mar 2009 Location: Portland, OR Posts: 4,004 Thanks: 303 Thanked 723 Times in 534 Posts	DIY Shower Water Heat Recovery There's a Wiki on the subject HERE. -AC_Hacker

04-11-10, 02:25 AM	#11
kbhale Helper EcoRenovator Join Date: Jan 2010 Location: Evansville IN Posts: 88 Thanks: 0 Thanked 1 Time in 1 Post	Sorry, I don't have any data. All I do know is that the barrel is warmer after I take a shower. I plan to put a insulation blanket around the barrel to keep the heat in it and under it. Hopefully this will help increase and maintain the overall temp in the barrel for better pre heating. My biggest problem was getting a good seal on the barrel. I did not put in a drain valve. Should have. Mine is all plastic. Peeing in it won't hurt it. I don't at the present time see any reason to worry about build up. A dose of lye once a year for hair balls should do it. If you can do it on the cheap go for it. It will save you some money over time. I'm buying material now to build my second water tank. It will be used to provide hot water and help heat the home. Do plan to keep the barrel in front of the tank for pre heating domestic water.

11-29-10, 11:42 AM	#16
AC_Hacker Supreme EcoRenovator Join Date: Mar 2009 Location: Portland, OR Posts: 4,004 Thanks: 303 Thanked 723 Times in 534 Posts	I came across a FAQ by a company called ReTherm that makes grey water heat recovery devices. Q1. Does ReTherm have to be installed vertically? Can it be installed on the horizontal? A1. Installing the ReTherm unit vertically is the only way to obtain the highest level of heat recovery. Having the unit installed horizontally will only deliver 1/5th of the heat recovery compared to the vertical install. Q2. How much electrical power does ReTherm require? A2. None. No electrical hook-up is needed. Our drain water heat exchangers do not require any electricity to recycle hot water heat. Q3. How long does it take to complete a typical household installation? A3. New Construction - Installing ReTherm as the home is being built requires 1-2 man hours. Retrofit - Installing ReTherm into an existing home typically requires 4-6 man hours. Q4. Can ReTherm be used to collect the heat from my hot water baseboard radiator piping? A4. No. The hot water that flows through the baseboards, radiators or through the in-floor heating pipes is never thrown away. It is a "closed-loop" pipe system that reuses the same water day after day, year after year. Q5. Can ReTherm be installed as a do-it-yourself project in a home? A5. Yes. The skills and knowledge required to properly install a ReTherm unit are basic. Many DIYers have completed their own ReTherm install. Q6. Will ReTherm cause any problems for my private septic tank? Will it prevent it from working properly? A6. No. Contrary to common perception septic tanks do not require any warm or hot water in order to function normally. Q7. How long is a ReTherm unit expected to last? A7. Since ReTherm units have no moving parts and are built entirely of durable copper the lifecycle is expected to be 40 years plus. Q8. Will ReTherm be more effective if it is insulated? A8. If the unit is installed in an area that is unheated or is normally less than room temperature then we recommend that the unit be insulated. However, if the unit is installed in an area that is maintained at room temperature insulating the unit is optional. Q9. Is hard water a problem for ReTherm? A9. No. Minerals in water can leave deposits when heated to high temperatures. Unlike boilers and other water heaters the temperature boost delivered by a ReTherm unit is not high enough to cause mineral build-ups on the surfaces of the unit. Q10. Should the water pipe between the ReTherm unit and the water heater be insulated to prevent heat loss? A10. Yes, this is recommended especially if the water lines are copper. If the water lines are plastic the heat loss from un-insulated pipes will be negligible since plastic is such a poor conductor of heat. Q11. Can ReTherm heat all of my hot water? A11. Although larger ReTherm units can recycle more than 60% of the heat from the shower they cannot replace the need for some type of "powered" water heater. ReTherm works with conventional "powered" water heaters. It cannot replace a powered water heater because it cannot heat water totally, it can only preheat water using the heat that is available from drain water.