geothermal loop pressure

Mark Custis

Nice news.

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geo loop pressure

Hello, I would like to know if it is better to run a higher or lower gpm on a loop? Waht are the effects of both?

Unknown

loop flow

well it depends how you define "better". you get higher heat transfer at higher flows at the cost of greater pumping power required, in europe they seem to care much more about operational costs and run much shorter loop lengths at a lower velocity and more of them than we do here.

Henry_6

Geothermal Loops

The Europeans also use brazed plate heat exchangers to recover latent and sensible heat during the heating season by freezing the ground surrounding the ground loop. This allows a 1/3 hp circulator to recover sufficient input for a 5 ton heating unit (W/A or W/W) to develop leaving air temp of 100-105 f. The result is much better performance than the sensible heat machines, at a lower total operating cost.

Mark Eatherton

Solar geo and seasonal storage

http://www.roth-usa.com/usa/home.cfm

Looks interesting.

ME

Mark Eatherton

More info...

http://www.roth-usa.com/usa/pdf/PR SolarGeo Forum.pdf

ME

Mark Custis

TY Mark

Nice news.

Henry_6

Roth Geothermal

This looks very much like a latent heat system. The challenge is making it reversible so that heating and cooling can be part of the operating parameters. It is very difficult to make a geo machine that is reversible and operating under the normal conditions of a latent heat system. It requires several components in addition to a reversing valve to absorb the (0%-100%-0%-100%) operation of a hydronic heat pump. It is much easier with an air to air because the operating refrigerant charge is about the same. I have had these systems in the field since 1988. The concept is excellent for a Northern climate( >5,500 DD) and they can be used to recycle waste heat for DHW. More to come.