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Old 02-12-13, 10:52 AM   #10
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Originally Posted by randen View Post
In deed the installed ground loop is only 4 ton but this is a continuous demand rate. The 5 ton GSHP will only require 5 Ton worth of heat on occation... At 6:00 am I can ramp up for the 5 ton for a couple hrs till I get into the shop then drop back to 3 ton while I'm there working...
OK, I just want to caution you, and this is a BIG CAUTION... but your 4 Ton loop is, as you said a rate. And your compressor capacity is a rate.

So, this is my theory:

When you draw heat from your loop, you have many, many feet of pipe that go through the earth, but the earth only oozes heat, it releases it slowly. The water in your pipes can release it's heat very fast to your HX. If you try to draw heat 20% faster from your loop field than it can produce, you will quickly exhaust the heat in the water, well before you exhaust the heat in your field.

If you are actually going to do this, please be sure that you are sitting in front of your system, close to the OFF SWITCH and be sure that you are continuously monitoring...

Because, if I am right, things will change quite suddenly.

I experienced this myself on a very small scale, It was a hot day in August, I has a tiny 450 watt compressor drawing heat out of a 12 foot deep hole, and the loop froze in a matter of minutes (a very few minutes).

randen, you're my hero, I want you to stay that way.


I'm not an HVAC technician. In fact, I'm barely even a hacker...

Last edited by AC_Hacker; 02-12-13 at 10:59 AM..
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