C L I M A T E M A S T E R W A T E R - S O U R C E H E A T P U M P S
18
C l i m a t e M a s t e r Wa t e r- S o u rc e H e a t P u m p s
Tr a n q u i l i t y 1 6 ( T C ) S e r i e s
R e v. : 2 5 J u l y, 2 0 1 7
Ground-Loop Heat Pump Applications
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 13. All earth loop piping materials should
be limited to polyethylene fusion only for in-ground
sections of the loop. Galvanized or steel fi ttings should
not be used at any time due to their tendency to
corrode. All plastic to metal threaded fi ttings should
be avoided due to their potential to leak in earth
coupled applications. A fl anged fi tting should be
substituted. P/T plugs should be used so that fl ow can
be measured using the pressure drop of the unit heat
exchanger.
Earth loop temperatures can range between -4
to 43°C. Flow rates between 2.41 to 3.23 l/m per
kW of cooling capacity is recommended in these
applications.
Test individual horizontal loop circuits before backfi lling.
Test vertical U-bends and pond loop assemblies prior to
installation. Pressures of at least 689 kPa should be used
when testing. Do not exceed the pipe pressure rating.
Test entire system when all loops are assembled.
Flushing the Earth Loop
Upon completion of system installation and testing,
fl ush the system to remove all foreign objects and
purge to remove all air.
Antifreeze
In areas where minimum entering loop temperatures
drop below 5°C or where piping will be routed through
areas subject to freezing, antifreeze is required.
Alcohols and glycols are commonly used as antifreeze;
however your local sales offi ce should be consulted
to determine the antifreeze best suited to your area.
Freeze protection should be maintained to 9°C below
the lowest expected entering loop temperature. For
example, if -1°C is the minimum expected entering
loop temperature, the leaving loop temperature would
be -4 to -6°C and freeze protection should be at -10°C.
Calculation is as follows: -1°C - 9°C = -10°C.
All alcohols should be premixed and pumped from
a reservoir outside of the building when possible or
introduced under the water level to prevent fumes.
Calculate the total volume of fl uid in the piping system.
Then use the percentage by volume shown in table
2 for the amount of antifreeze needed. Antifreeze
concentration should be checked from a well mixed
sample using a hydrometer to measure specifi c gravity.
Table 2: Antifreeze Percentages by Volume
Type
Minimum Temperature for Low Temperature Protection
-12.2°C
-9.4°C
-6.7°C
-3.9°C
Methanol
100% USP food grade Propylene Glycol
Ethanol*
25%
38%
29%
21%
25%
25%
16%
22%
20%
10%
15%
14%
* Must not be denatured with any petroleum based product
CAUTION!
The following instructions 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.
CAUTION!
CAUTION!
CAUTION!
Ground loop applications require extended range
equipment and optional refrigerant/water circuit insulation.
