System information

14
Geothermal Applications
ClimateMaster: Smart. Responsible. Comfortable.
Figure 5: Typical “Laydown” Header
Figure 4b: Typical Header Through 5 Tons
Closed Loop Design/Installation Guidelines
Headers that utilize large diameter pipe feeding the last
circuits should not be used. PE 1-1/4” IPS pipe requires 9.5
gpm [36 l/m] to attain 2 fps [0.6 m/s] and since increasing
the fl ow through the last circuit would also require increasing
the fl ow through the other circuits at an equal rate as well,
we can estimate the fl ush fl ow requirements by multiplying
the number of circuits by 9.5 gpm [36 l/m] for 1-1/4” IPS. For
instance, a 5 circuit loop would require 5 circuits x 9.5 gpm/
circuit = 47.5 gpm [5 circuits x 36 l/m per circuit = 180 l/m
or 3.0 l/s] to attain fl ush fl ow rate. This is clearly is a diffi cult
fl ow to achieve with a pump of any size.
Header Layout - Generally header layouts are more cost
effective with short headers. This requires centrally locating
the header to all circuits and then bringing the circuits to the
header. One of the easiest implementations is to angle all
trenches into a common pit similar to a starburst. This layout
can utilize the laydown or ‘L’ header and achieves reverse
return fl ow by simply laying the headers down in a mirror
image and thus no extra piping or labor. Figure 5 details a
“laydown” header.