Trane GETB Installation Manual page 15

Using Antifreeze
In areas of the country where entering
water temperatures drop below 45°F
or where piping is being run through
areas subject to freezing, the loop
must be freeze protected by using an
approved antifreeze solution to pre-
vent the earth loop water from freez-
ing inside the heat exchanger.
Methanol and glycols are the most
commonly used antifreeze solutions.
Consult your geothermal unit supplier
for locally approved solutions in your
area.
Propylene glycol is not recommended
in installations where the water tem-
perature are expected to fall below
30°F . At extreme temperatures, the vis-
cosity increases to the point where
normal loop circulating pumps may
not maintain proper flow.
If propylene glycol is the only locally
approved solution for anti-freeze,
good engineering practices should be
used to achieve the desired flow.
Calculate the approximate volume of
water in the system by using the re-
quirements detailed in Table 8, Water
Volume. Add three gallons to this total
to allow for the water contained in the
hose kit and geothermal unit.
WSHP-SVN08B-EN
Installation
Table 3: Antifreeze requirements based on volume
Type of Antifreeze
Methanol
Propylene Glycol
Minimum Temperature for Freeze Protection
10°F 15°F 20°F
25% 21% 16%
- - -
25°F 30°F
10% 3%
- 6%
15