Dxgshpwh (ground source heat pump water heater)

[Daox]

This was quite the productive weekend for you. Great updates.

[AC_Hacker]

Originally Posted by MEMPHIS91

AC
I wish I could take credit for all this, sure it was my idea to put it all together but I'm just pulling from hundreds of other peoples good ideas.

MEMPHIS91,

I think that this is, in reality, the only way civilization progresses.

-AC

[AC_Hacker]

Originally Posted by MEMPHIS91

Gotcha, sorry I was thinking I would be measuring this under pressure, but that makes more sense. Just fill it to the top and pull the anode out. Perfect because I have a kill-a-watt meter and aquarium thermometer.

I wonder if you will even need an anode? I have a hunch that electric heater elements induce a small voltage into the water in the tank, which accelerates galvanic erosion. Since you are not going to use electric elements, you may not need that anode.

Maybe a better use for the anode hole would be a couple of temperature sensors, permanently mounted. One placed high and one placed low, for future data logging, or performance monitoring.

-AC

[AC_Hacker]

Really great job!

You have done a good job of utilizing the conditions and assets that are immediately available to you:

• soft ground
• a pond
• low-tech drilling method
• sloping ground to drain water overflow back into the pond
• using the mud pump as a really big muscle

Just great! I hope that more of your Southern Neighbors, who are also blessed with easily-drilled soil take advantage of your example.

The only improvement that I can think of is that you can get glue-on male & female screw-together connectors for your drilling pipe, which might make assembly & disassembly, and storage and transport easier.

Awesome!

-AC

P.S.: I just wanted to say, that at the beginning of your thread, you said that you wanted to "give back". Well, MEMPHIS91, your ideas, great descriptions and photos have done just that. If I may be so bold, on behalf of everyone who has shown interest in what you are doing, I'd like to send out a big thank you!

And you're not even done yet!

[randen]

MEMPHIS91

I think you have impressed the big gun, AC Hacker. You have checked all the boxes on how efficient one can heat water. Plus you have done it with your own two hands. Many talk the talk but we have seen that you actually are flying along with a super project. I like many are on the edge of our seats to see what the final numbers will be.

Randen

[jeff5may]

Originally Posted by AC_Hacker

I wonder if you will even need an anode? I have a hunch that electric heater elements induce a small voltage into the water in the tank, which accelerates galvanic erosion. Since you are not going to use electric elements, you may not need that anode.

Maybe a better use for the anode hole would be a couple of temperature sensors, permanently mounted. One placed high and one placed low, for future data logging, or performance monitoring.

-AC

With the rig at hand, the galvanized pipe union would serve as the anode if the factory anode is removed. The zinc plating would dissolve first, then the cast iron. As long as this fact is known and understood that the union should be swapped out before it eventually fails as prevention, then removing the anode rod would be ok. Otherwise, I would find another way to run sensors. The only common metal less noble than zinc is magnesium.

If ultimate precision is not paramount, the thermometers need not be in intimate contact with the waters. Most manufacturers place their sensors in the heating element fittings or on the outside wall of the tank. A very few have custom, threaded fittings or are inside a well of some sort. It seems that on the wall, somewhere under the insulation envelope would be pretty close.

[MEMPHIS91]

WOW! Thanks for all the comments guys.
Daox, it was in fact a good weekend, its pretty easy to work hard when a project is coming together so well.

AC, Thanks man! The true life of a hacker, to use what he has around him, cause he is to cheap or to broke to buy it. lol JK

Concerning the anode, I have 8 grains per gallon of hard water, so I would like to keep it in.

Randen, Thanks man, trust me I'm on the edge of my set as well.

Jeff, yeah that is what I was thinking to. Good data is awesome, but I think it can be close enough from the outside of the tank.

UPDATE! SHE IS ALIVE!


I got everything wired in, tank filled with water, and I pulled a crazy low long vacuum, made sure it held and started to fill. Low side came on up to 15 psi. Pulling 2.3 amps. With a high side temp of 136F. Then the low came up to 17 psi (on its own, nothing added) and temp was 145. All of a sudden it jumps to 25 psi with a temp of 162F pulling 2.5 amps!! That was only running for 20 minutes. I got scared and unplugged it. The tubing going into the ground was frosted from half way down the evap tube all the way into the ground.
Is this ok? It felt like the evap tube was surging some, not a constant flow. I mean 163F is HOT. I just don't want to burn up the compressor.
Thoughts? Once I get it running right, I'll start running test.

Thanks again guys for following along with me on this project.

EDIT: I'm thinking i might have put to much oil/ or wrong size cap tube. I guess it could be to short cause the evap to flood.

[randen]

MEMPHIS91

Sounds like you have a great machine. I think the pressures and temps are good. Maybe a tad over-charged but I would let it run. You did charge your system according to the manual supplied with your system, right.??? HeHe. I found that my sweet spot was 18 psi but my evaporator is a different temp than yours. You could very-well be in the sweet spot for your DX evaporator. Wire in your tank temp switch (lower) turn it to a lower temp setting 110-120 and enjoy the moment.

You're a little concerned about the life of your compressor but it is used??? recycled from the scrap pile?? If the compressor motor stalls or overheats you have two safeties your circuit breakers and a thermal overload. Don't forget your now operating at lower pressures than with the R22 refrigerant. It should be just fine.

You may want to concentrate the extra copper turns to the top portion of the compressor were the bulk of the heat is generated with the compressing of the refrigerant in the scroll to a lessor degree with the motor windings.

2.5 Amps!! 300watts!!! vs a 3000watt resistant element?? You deserve some bragging rights!!!

What is the cost of electricity in you area?? We're at $0.22/Kwh all in.

Randen

[AC_Hacker]

All good from what I see.

You may already know this, but when you are charging, it takes a bit of time for the system to adjust to the change in charge... like maybe 20 to 30 minutes for each change. So don't be in too much of a hurry.

I'd be interested to know a few more details about your oil. How much did you add? Did you completely drain the oil and the re-fill with fresh oil?

I was going to suggest that the oil may have been perfectly OK, if the compressor had not been sitting open for any appreciable amount of time. But you finished the system before I could say anything.

At any rate, I'm very interested to know what your COP tests look like.

Best,

-AC

[jeff5may]

With a cap tube metered system, you charge by superheat. At the muffler intake, you should always have 10 degF or more to ensure you are not flooding your evaporator. The other thing to watch is discharge pressure. As your hot water tank rises in temp, the discharge pressure will follow. Normally, it will go up around or above 200 psig. For your rig, 250 psig will give you a 125 degF condensation temp; above that level of pressure, your efficiency will pay dearly.

It all depends on how hot you want or need your hot water to be, as well as your consumption habits.