circulator selection

What does it do with 50/50?

 

yep, but you compensate for a lower reynolds number with the amount of pipe in the ground. What number are you getting?
Reynolds goes up with higher viscosity at lower temps, when you need it most. That is good.

 

Then you spend much more on pumping and loose more heat transfer, keep glycol at 25%.

 

I ended up going with ethanol with my system to get a half decent Reynolds number.

 

I'm getting a Reynolds number of 1313 with 4 800'x1" loops per gshp
26-99 pumps 9 gpm. according to the climate master calculator.

I'm getting a Reynolds number of 1430 with 4 800'x3/4" loops per gshp
26-99 pumps 8 gpm. according to the climate master calculator.

Both with 24% glycol

They suggest a Reynolds number above 2500 is needed.

To get the number higher I can lower glycol %

 

I'm not real happy about using a flammable liquid. whats all involved?
Dangerous when your flushing?

 

I was able to dilute the ethanol and fill the system from outside. The basement window is in a very convenient spot.
Once dilute, I'm pretty sure it's fine...

 

BOOM

 

I went back and skimmed that safety sheet.... it's been 5 yrs since reading that. I would say flushing MUST be done outdoors. (although they do have a lengthy list of safety rules for inside flushing) Like I said, my basement window is at a very convenient spot and doing all the filling/flushing from outside was not a issue for me.... so no BOOMs here Mark. It's safer once diluted, but it's still consider flammable at a 25% mixture.

I always have to laugh at this one..... "No source of ignition within 20’ of the mixing/diluting operation, including welding and smoking." - really? welding and smoking are a ignition source..... lol

 

Don't worry too much. Do not sacrifice your antifreeze. You compensate for the lack of higher turbulence with the larger loop.

 

Thanks Doc.

I understand now.

 

Reynolds number is important to minimize loop field. Turbulent flow less important if field is generously sized.

 

Can anyone give me a reality check?

Running one 3 ton w2w Bosch unit on a loop field consisting of X3 800' runs of 1"
To a short run of 1 1/4" header to 1" rubber hose to the unit.

Attached is a climate master work sheet with the details and lengths. Just wanted to make sure I understand that 1 26-99 pump will do the job.

I'm actually going to be using a Bosch w2w unit that list exchanger loss at a bit under 11 ft hd @ 9 gpm.
so the total ft hd with a Bosch unit vs climate master unit should be about 4-5' less I think.

Thanks for helping me clear this up!

 

A spread sheet beats the back of an envelope every time. Your numbers are correct.

 

Thanks Mark I thought I had this nailed weeks ago, but you had me questioning my methods.

 

Total pressure drop is around 22 ft/hd at 9 gpm, a single flow center with a 26-99 will give you actually 9.8 gpm flow.

All good.

 

Thanks Doc

 

Andy,

Enjoying this thread.

Seems like you are constraint loop field space. Not sure what your lot size is and zoning setbacks you have to deal with.

Are you going to have enough space to stockpile the excavated soil while trenches are opened?

5' x 7' trench profile is a lot of dirt to move and stockpile. Is your ground sand or clay?

Another option may be going with a vertical slinky loop if your ground is stabile. Dewayne Dean has a vertical slinky loop.

My AHJ required all piping in the ground loop exposed and pressurized before signing off to backfill.

Another thing to think about is the impact of cutting tree roots during excavation.

Bob G.

 

Hey Bob thanks for the reply.

My local Authority doesn't have any regulations like that.

I have plans to pressurize each loop before back fill. But I will have to back fill each loop as I go.
I'm bringing each trail into the building with a manifold inside.

Mostly Clay here. I thought I had plenty of room on my 1 anchor lot. But with a well, septic, house, deck, and shop. Space without trees is limited.


I hope to keep learning! Thanks!

 

"Horizontal" slinky loop.

Edit: Oh, get it. In a "vertical" profile.