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Discussion Starter #1
So my fiance and I are building a home that is well water fed and I am looking to capitalize on a relatively constant source of cool water springing forth. Originally, I was looking to add connectivity to our geothermal cooling but was told by the company installing the closed loop that the system was designed to the needs and tolerances of the home and therefore they would not warranty it if I "tapped" in.

However, the salesperson\ech I spoke with suggested we could utilize the water from the well prior to it being fed to our primary water heater. He posited that we could place an additional water heater in front of our primary water heater to act as a giant reservoir to the watercooled computers. Water would circulate between the computers and water heater 1 gradually gaining some heat. Then whenever hot water was used in the house, shower, dishes, laundry etc. the heated water from water heater 1 would flow to replace water in water heater 2 and be heated to the necessary storage temperature. Example:

Well -> Water Heater 1 (Reservoir) -> Water Heater 2 (for household use)

Question #1

This sounds like a grand idea to me but I am curious if there is any issue with the water being used in cooking, cleaning, eating etc. The piping from water heater 1 would be plastic and "safe" going to the computers in our office and water heater 1 would meet all standard codes. All my water blocks are copper and I can't think of any reactive components. I am running an antifreeze coolant in the current setup but would thoroughly clean all hardware during the turnover.

Question #2

What size water heater is best? How quickly will 2 water cooled computers heat it if it were say 80 gallons at approximately 50 deg F? I would be cooling 2 overclocked cpus and a total of 3 graphics cards. Basically, what kind of calculations should I be using. I suppose I will need to calculate pump heat dump as well but I still need to figure pump head height need to make it from the mechanical storage room to the 2nd story office.

This is a work in progress and I appreciate any and all constructive criticism or advice. I hope to be able to enlighten others with my results.

Thank you.
 

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Discussion Starter #2
Was looking around for heat dump info and found a possible comparison in an electric element used to heat an electric water heater. At max load of both computers I would estimate that I wouldn't be dumping more than 1000 watts. We don't leave the computers on and they are rarely used together, especially at max load.

I am also considering a heat exchanger placed within water tank 1 so that I could have a closed loop and not worry about running everything up and through the computers. That may require more maintenance overall given bacterial growth since I wouldn't want to have a toxic substance in the closed loop. "Safety First!"

Found this information on Wikipedia:

http://en.wikipedia.org/wiki/Water_heating

Natural gas in the U.S. is measured in CCF (100 cubic feet), which is converted to a standardized heat content unit called the therm, equal to 100,000 British thermal units (BTU). A BTU is the energy required to raise one pound of water by one degree Fahrenheit. A U.S. gallon of water weighs 8.3 pounds (3.8 kg). So, to raise a 40-gallon tank of 55 °F (13 °C) water up to 105 °F (41 °C) would require (40 Ã- 8.3 Ã- (105 − 55) / 100,000) BTU, or approximately 0.17 CCF, at 100% efficiency. A 40,000 BTU/h heater would take 25 minutes to do this, at 100% efficiency. At $1 per therm, the cost of the gas would be about 17 cents.
In comparison, a typical electric water heater has a 4500 watt heating element, which if 100% efficient results in a heating time of about 1.1 hours. Since 16,600 BTU is roughly 4.9 kWh, at 10 cents/kWh the electricity would cost $0.49. Operating a shower at 2.5 gpm and 104 °F (40 °C) is equivalent to operating a 19.8 kW appliance [ ref. w computes 13.2 kW, but that is for 20 degree C increase instead of 30 ].[2] In the UK, domestic electric immersion heaters are usually rated at 3 kilowatts.[3]
 

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seems to me like you would need some kind of filtering system in place before the water goes into the resevoir (water heater #1). It also sounds like your going to need quite the pump to go from a mechanical room (located in the basement I assume) up to a second story, through the computers and back.

It sounds do-able, but I would be more concerned with impurities clogging up your blocks than impurities from your pc to the drinking water. If your just running the H2o through some tubing and copper blocks, there is nothing to worry about with contamination for your drinking water.

I'm not sure how much the loops would heat up your water in tank #1, but, as long as people in your house use the restroom often enough, I would think that that would be enough cold water intake to keep things chilly. Some tiolets use three gallons a flush. If it starts to get warm during a 12 hour starcraft session, that would be a good time to water the lawn, or have your kids take a shower lol.
 

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Discussion Starter #4
Exactly what I was thinking. Draw a bath to relax the muscles after the 12 hour SC session.


I forgot to mention we will have a water filtration unit in place right off the well flow. I am looking into the product linked below. It is interesting in that it controls scale by stabilizing magnesium and calcium ions. They are effectively crystalized and washed away without being able to bond.

http://www.lapurewaterproducts.com/w...lt-system.html

I know of a number of aquarium pumps that can manage the lift 2 stories but keeping it low wattage and low heat may be an issue. By using a heat exchanger and closed loop I suppose I can more adequately recover fluid speed with the help of gravity. (maybe?)
 

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It's going to take a halfway decent the pump to push water 2/3 stories strait up isn't it, I've had fish pumps that couldn't push much more than 10ft, I'm guessing 25-30 Head (ft) from the basement and the returning water should help aid the pump.
 

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Discussion Starter #6
I know of a number of pumps that could reach the pump head height but my goal would be to keep the heat and electrical cost down as much as possible. I would be using 1/2 id tubing so the pump should have more pressure.

According to Martin's Liquid Lab, you really don't need to move more than 3-5 GPM. I would also most likely have a reservoir upstairs with pumps leading out to the computers individually. That way it would be much less work for the pump downstairs. Thanks for the comments USForces and bob808!
 

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Found out that according to building code the piping will have to be 3/4 ". Code states that if tubing is passing through multiple levels it has to be at least 3/4". Not sure but this might affect pump selections.
 

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You will need to use a continuous duty pond or industrial pump. They can be found for under $70 and should suit your needs perfectly. I am currently pumping oil though a radiator outside my house using a pond pump. If I remember the numbers correctly, it has a suction force of 90ft and head pressure of 300ft. A pump this large will need to run on 120/240VAC. You'll want to run 1.5-2" pipe from the pump in in order to keep the pressure down. A pump that large won't slow down for small pipe-- it will just force the pressure way high and heat up the pump.


I bought my pump on eBay. It would be impossible for me to find the same pump locally.

Contamination will not be a problem. You're running the same clean water you drink though your computer-- meaning the blocks won't get clogged. Since you will only be running water over copper and PVC/Flex hose, the computer can not contaminate the drinking water.
 

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As noted above I think the biggest issue would be water purity. If your well water is anything like ours, there is a ton of iron in it. If it can clog up a shower head given enough time, it most certainly could screw up your computer's copper components. Our's still has enough iron in it after 2 filters and a water softener to stain the shower walls....
 

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ok boys and girls u dont run tap water threw ur computer or hook it up to ur heater go on line and buy a plate exchanger 15-30 plate they are made out of stainless so no worrys


so now u take the cold feed line to heater and u send it threw the plate ex and into heater u take ur loop water and u hook it up to the hot side of the plate ex make sure to put ur rads after plate ex to get maximum heat dump into water line so the water entering the heater is around same temp as ur loop water

now unless ur water heater is right next to ur computer it will make a paine to run extra plumbing for this

and u dont need a pump for cold feed line city water line has plenty preshure to work its way threw the plate ex but u will need a heavy duty pump for ur loop if ur computer is on the second floor and heater is in the basement
 

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Discussion Starter #11
This defeats the proposed purpose of capturing heat output from the computers. I am trying to capture the heat in a hot water tank so I can reduce the necessity of heating it with an element for other household purposes. Ideally, it is to provide quiet and effective cooling for overclocking but I also wish to reduce our energy usage.
 

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the only problem i see with this system is... when your done with your showers or using the hot water... the tank will fill right? so that leaves your reservoir tank filled.. the waterflow has to stop and your computers will in turn start warming up again...

thats all i see is that with cooling a computer you have to constantly keep the water running through it...
 

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water in hot water tank is 50-80c water in my rez is 19c at full load
i wonder wich is better

pree heating cold line is the best way to go about it

u can buy 10 ft of 4" abs pipe 2 end caps run water line inside coiled up , abs pipe becomes ur rez and heats coiled up water line insulate the abs pipe and ur pree heating 40-60ft of coiled up cold line wich will give energy saveings and good computer cooling when no one is using hot water its heating the cold line when some one is useing it the cold line is cooling ur loop and takeing in heat from loop

if ur not qite sure how the abs pipe thing works pm me i will send u a drawing and if u want i can build it for u for a small fee

as for useing hot tank as ur rez its a bad idea as it will take forever to get hot and once it dose it will take 20 360 rads to cool it back down so ur computer wont go into melt down
 

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I can see this working, and IMO it might work quite well. I have thought about something similar to this, but didnt think pumping up 2 stories was really a good idea. The water in the first hotwater tank, should stay around the tempature of the ground 3 feet down. And by time the water starts to warm up, some hot water would be used by someone/something. You get the benifits of cooling your computers down with cold water and no need for rads/fans. And you take water that is cold, and warm it up a bit so your hotwater heater doesnt have to work so hard and use so much energy. I doubt you will have to worry about condensation because the water in you closed loop probably wont reach below room ambeint.

I think keeping the loop closed would be smart. No lime or calcium build up on blocks, and no mystery water in you glass and food. And instead of using PTnuke or such, you can use REAL silver fittings and killcoils. They, in theory, will keep the loop clean without any unnessicary risks.

The only problem with an heat exchanger like that is that the water cant stop. With the 50/80 gallon res the cold water is there waiting to dissapate the hot energy. And can be used repeatidly until it is needed in the house. 80 gallons of cold water has a lot of "cold" energy if I can say it like that.

When you build this make the cold inlet into the watertank is at the bottom of the tank. With your rad/exchanger. Have the "warm" outlet at the top of the tank. So the warmest water is at the top ready to leave, and the coolest is at the bottom cooling your loop.

I am very interested in this, and if it turns out to be as good as I think it might, I wanna try. Something about using wasted energy, and putting it to use. Rep'd and Sub'd
 

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Discussion Starter #15
I'm still open to the idea of tapping in to our geothermal but the company we are working with is hesitant to added extra load. I suppose if I can give them some rough thermal calculations they may be more apt to work with me but so far they have stated loop and equipment has been sized to the home and are nervous to expand.

Another thing to keep in mind is that we ordered a kill switch for Xcel (power company) to utilize in their savers program. They will offer us %50 off our total heating bill (measured with a separate meter) or 20% off our entire electric bill. As proposed by someone else, if we hookup to the geothermal heat pump we would run the risk of Xcel controlling the power to that pump and shutting it off at determined times. The max amount of time they could turn it off would be 12 hours but I'd rather not leave them in control of computer usage.

However, if we have them take %20 off the total electric bill it would be less expensive to leave the computers on for longer periods -> hotter water in the reserve tank -> less gas need to heat the primary hot water tank. I am working on getting specs for the geothermal. I recently was reminded that they plan to introduce a 50 gallon holding tank for something but I'm not sure what the primary use will be.
 

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Discussion Starter #16
Well, the house is built and all equipment is in place. Unfortunately, there was something I missed originally on the geothermal bid. They have placed a 50 gallon buffer tank after the geothermal heat pump and before the hot water heater. This tank captures the excess heat from the geo pump as a sort of recirculation system and provides heated water to the hot water heater.

I have decided to not play around with altering the system that was installed but I have some alternatives. It just so happens that I retained the 40 gallon water heater from our old home and since I already paid to have the pex tubing run to the computer room...

The new system will be a closed loop system with the 40 gallon water heater as the reservoir and it will be circulated from the mechanical room by a high head aquarium pump I have laying around. I'm looking for new thoughts at the moment on how to handle the circulation through the computers once I get it up the two stories. My thought was to have a second reservoir located in the room with the computers and utilize the WC pumps I currently have installed. With some quick disconnects, I may even be able to keep the rads I have in place and retain some portability with these machines.

Please offer any thoughts you may have on the topic. Specifically, I am interested in

1. What to use as a secondary reservoir?
2. Will Swiftech MCP 655 pumps be adequate in circulating the water from that secondary reservoir?
3. What liquid would be best to use assuming an approximate 45 gallon fill?
4. Would pressure from the primary pump at the secondary reservoir cause issues in back pressure on the returns from the Swiftech pumps?
5. Should I just use a heat exchanger at the secondary reservoir and work with a large water loop and a small non-water loop?
6. What should I use as heat exchangers?

Thanks in advance for any feedback.
 
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