T Therm Geo TST-***, Installation & Operating Instructions Manual

Page: 15 / 53

12/03/2012
13 GI301
Antifreeze
When considering the earth loop solution, water quality is very important. TTHERM GEO recommends a
minimum of soft water (not well water) treated with 2 oz. of household chlorine bleach for each 10 gallons of
total volume. TTHERM GEO’s recommended antifreeze concentration is 22% which will yield a freeze
protection of 18° F. This concentration of glycol requires additional additives to protect the system. TTHERM
GEO recommends Enviro-Guard HD propylene glycol for this reason.
Over antifreeze protecting a loop field decreases pumping capacity when the loop gets cold and reduces thermal
transfer. Under protecting a loop field will cause the THERM GEO heat pump to take action protecting itself
from damage. This action will result in a loss of geothermal capacity, and AUX heat may be required to
maintain the temperature in the home.
Table 2 – Approximate Fluid Volume (gal) per 100ft
Pipe Size Volume Pipe Size Volume
¾” IPS SDR 11 3.02 1” 4.1
1” IPS SDR 11 4.73
Rubber Hose
1.25” 6.4
1-1/4” IPS SDR 11 7.55 1” 4.5
1-1/2” IPS SDR 11 9.93 1.25” 6.8
Polyethylene
2” IPS SDR 11 15.36
Copper
Type M
1.5” 9.5
WARNING
PREVENTING FREEZE-UP IS INSTALLER/USER RESPONSIBILITY. DAMAGE CAUSED BY
FREEZE-UP IS NOT COVERED BY WARRANTY.
CAUTION
Softened water is recommended along with 2 oz. of common household chlorine bleach for every
10 gallons of water.
WARNING
NOT ALL GLYCOLS
PROVIDE THE SAME LEVEL OF CONCENTRATION. MOST GLYCOLS
DO NOT CONTAIN ENOUGH INHIBITORS FOR THE RECOMMENDED CONCENTRATION
LEVELS.FOR GEOTHERMAL SYSTEMS.
Open Loop
– An open system gets its name from the open discharge of water after it has been used by the heat
pump. A well must be available that can supply all of the water requirements of the heat pump along with any
other water requirements drawing off that same well. The well must be capable of supplying the heat pump’s
required flow rated for up to 24 hours per day for the coldest winter day.
Figure 6 shows the necessary components for water piping of an open system. First a bladder type pressure tank
with a “draw down” of at least 1-1/2 to 2 times the well pump capacity must be installed on the supply side of
the heat pump to prevent short cycling the well pump. Constant pressure well pumps need to deliver the GPM
flow rate of the TTHERM GEO heat pump and other possible consecutive demands. Shut off valves and boiler
drains on the entering and leaving water lines are necessary for future maintenance. A screen strainer is placed
on the supply line with a mesh size of 40 to 60 and enough surface area to allow for particle buildup between
cleanings. Hose kits are installed between the heat pump and ridged plumbing to reduce vibration transfer. Hose
kits have pressure temperature (P/T) plugs placed in the supply and discharge hydrant elbows so that
thermometers or pressure gauges can be inserted into the water stream. On the well water discharge side of the