Ground Loop Applications - Heat Controller HTV Series Installation, Operation & Maintenance Instructions Manual

Heat Controller, Inc.
Ground-Loop Heat Pump Applications
T
CAUTION!
represent industry accepted installation
practices for closed loop earth coupled
heat pump systems. Instructions are
provided to assist the contractor in
installing trouble free ground loops.
These instructions are recommendations
only. State/provincial and local codes
MUST be followed and installation MUST
conform to ALL applicable codes. It is the
responsibility of the installing contractor to
determine and comply with ALL applicable
codes and regulations.
T
CAUTION!
require extended range equipment with
refrigerant/water circuit insulation.
PRE-INSTALLATION
Prior to installation, locate and mark all
existing underground utilities, piping, etc.
Install loops for new construction before
sidewalks, patios, driveways, and other
construction has begun. During
construction, accurately mark all ground
loop piping on the plot plan as an aid in
avoiding potential future damage to the
installation.
PIPING INSTALLATION
The typical closed loop ground source
system is shown in Figure 6. All earth loop
piping materials should be limited to
polyethylene fusion only for in-ground
sections of the loop. Galvanized or steel
ttings should not be used at any time due
to their tendency to corrode.
HTV/HTD/HTH SERIES
GROUND-LOOP HEAT PUMP APPLICATIONS
 CAUTION!

The following instructions
 CAUTION!


Ground loop applications

All plastic to metal threaded ttings should
be avoided due to their potential to leak in
earth coupled applications. A anged
tting should be substituted. P/T plugs
should be used so that ow can be
measured using the pressure drop of the
unit heat exchanger.
Earth loop temperatures can range between
25 and 110°F. Flow rates between 2.25
and 3 gpm per ton of cooling capacity is
recommended in these applications.
Test individual horizontal loop circuits before
back lling. Test vertical U-bends and pond
loop assemblies prior to installation.
Pressures of at least 100 psi should be used
when testing. Do not exceed the pipe
pressure rating. Test entire system when
all loops are assembled.
FLUSHING THE EARTH LOOP
Once piping is completed between the unit,
Flow Controller and the ground loop (Figure
6a), the loop is ready for nal purging and
charging. A ush cart with at least a 1.5 hp
pump is required to achieve enough uid
velocity in the loop piping system to purge
air and dirt particles. An antifreeze solution
is used in most areas to prevent freezing.
All air and debris must be removed from the
earth loop piping before operation. Flush
the loop with a high volume of water at a
minimum velocity of 2 fps in all piping. The
steps below must be followed for proper
ushing.
1. Fill loop with water from a garden hose
through the ush cart before using the
ush cart pump to insure an even ll.
2. Once full, the ushing process can
begin. Do not allow the water level in
the ush cart tank to drop below the
pump inlet line to avoid air being
pumped back out to the earth loop.
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