danielz
Registered Users
Posts:17
 |
| 08/20/2008 7:07 PM |
|
I've been searching around for information about sizing Geothermal Flow Controller pumps..... Can anyone give me a brief tutorial on the whole area?
We are installing three separate Vertical loops, using 1in U-Bend piping...... feeding Climatemaster Tranquility 27 split units.
Loop 1: for a 5 ton (2 stage) system is three wells at 300ft deep, separated by 20ft and the grid is about 25 ft from the basement.
The system would require 15gpm at 5 ton and less in stage 1.
What would be the estimated head? and pump size (or two pumps) to handle this effectively?
Two other loops: using two TT026 (2.2 ton), 2 stage systems, each having two wells at 250ft.... so 500ft per loop, separated again....
I got myself in a bit of a jam, as in my situation, I needed to separately contract the well driller and the HVAC guys. I wasn't happy with the HVAC geodesigner run, so I increased my loop sizes on my own with the driller. The HVAC guy is upset and said it might have thrown "everythihng off"..... I can't believe that a larger loop would cause any problem for the internal design, other than the pumps (and the associated increase electric cost if I need more pump power)......
Anyone up for a tutorial on this? and any advice? I wanted to reduce my Aux usage in SE Pa. The recommended loops (5-ton recommended 700ft... I went 900, 2.2ton recommended 305ft... I went 500) Wouldn't that at lest give me some more room on keeping the EWT a bit higher in the winter?
|
|
|
|
|
|
|
geodean
Registered Users
Posts:518
|
| 08/20/2008 8:02 PM |
|
If all you did was make each loop longer, you have not "thrown everything off".
At 15 gpm the pressure drop on 3-300' foot wells is 12.4 ft of hd, on 3-266' wells it is 9.6 ft of hd. Not a huge difference.
This is not enough to require more pumping power.
More pipe in the ground will definitely give you better loop performance.
|
|
Dewayne Dean
PalaceGeothermal.com
Why settle for 90% when you can have 400%
We heat and cool with dirt! |
|
|
danielz
Registered Users
Posts:17
|
| 08/20/2008 8:22 PM |
|
Thank you for the quick response...
So then, then, do you think that Climatemaster flowcontroller single-pump units are fine for the 2x250 loops (2.2 ton)?
And, is the single pump still adequate also for the 3x300 loop? or would that one be better with the dual-pump?
btw, each loop set is likely parallel.....
appreciate the sanity check...
|
|
|
|
|
geodean
Registered Users
Posts:518
|
| 08/20/2008 8:27 PM |
|
| My loop pump software calculates that a single pump flow center will do the job on each of your heat pumps |
|
Dewayne Dean
PalaceGeothermal.com
Why settle for 90% when you can have 400%
We heat and cool with dirt! |
|
|
danielz
Registered Users
Posts:17
|
| 08/20/2008 8:32 PM |
|
Perfect! that was what I was told in the original geodesigner run, where the loops were smaller. I didn't think that I increased things so far that it would be an issue....
thank you!
|
|
|
|
|
engineer
Registered Users
Posts:311
|
| 08/21/2008 2:54 AM |
|
I'm with Dewayne on this. More pipe in the ground is nearly always good...costly maybe, but good.
Your HVAC guy may be papering over the insecurity of ignorance with bluster.
Be sure loop flows are sufficient for turbulent flow in individual u-tubes. |
|
Without data, you only have an opinion. |
|
|