Heat Controller HEV/H 사용자 설명서

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Heat Controller, Inc. 
HEV/H SERIES
 
Installation, Operation & Maintenance
GROUND-LOOP HEAT PUMP APPLICATIONS
Table 3. Antifreeze Percentages by Volume
 
Type 
Minimum Temperature for Freeze Protection
 
  10°F [-12.2
°C]
 15°F 
[-9.4
°C]
 20°F 
[-6.7
°C]
 25°F 
[-3.9
°C]
Methanol 
  25% 
21% 
16% 
10%
100% USP food grade Propylene Glycol 
     38%   
      30%  
    22%   
  15%
Table 2: Antifreeze Percentages by Volume
Low Water Temperature Cutout Setting
CXM Control
When antifreeze is selected, the FP1 jumper (JW3) 
should be clipped to select the low temperature (an-
tifreeze 13°F [-10.6°C]) set point and avoid nuisance 
faults (see “Low Water Temperature Cutout Selection” in 
this manual).  NOTE:  Low water temperature operation 
requires extended range equipment.
pressure is reached. Open the return valve and a 
pressure surge will be sent through the loop to help 
purge air pockets from the piping system. 
4.  Notice the drop in fluid level in the flush cart tank 
when the return valve is shut off. If air is adequately 
purged from the system, the level will drop only 1-2 
inches (2.5 - 5 cm) in a 10” (25 cm) diameter PVC 
flush tank (about a half gallon [2.3 liters]), since 
liquids are incompressible. If the level drops more 
than this, flushing should continue since air is still 
being compressed in the loop fluid. Perform the “dead 
head” procedure a number of times.
Note: This fluid level drop is your only indication of air in 
the loop.
Antifreeze may be added before, during or after the 
flushing procedure. However, depending upon which time 
is chosen, antifreeze could be wasted when emptying the 
flush cart tank. See antifreeze section for more details.
Loop static pressure will fluctuate with the seasons. 
Pressures will be higher in the winter months than during 
the cooling season. This fluctuation is normal and should 
be considered when charging the system initially. Run the 
unit in either heating or cooling for a number of minutes to 
condition the loop to a homogenous temperature. This is 
a good time for tool cleanup, piping insulation, etc. Then, 
perform final flush and pressurize the loop to a static 
pressure of 50-75 psi [345-517 kPa] (winter) or 35-40 psi 
[241-276 kPa] (summer). After pressurization, be sure 
to loosen the plug at the end of the Grundfos loop pump 
motor(s) to allow trapped air to be discharged and to insure 
the motor housing has been flooded. This is not required 
for Taco circulators. Insure that the Flow Controller provides 
adequate flow through the unit by checking pressure drop 
across the heat exchanger and compare to the pressure 
drop tables at the back of the manual.
Antifreeze
In areas where minimum entering loop temperatures drop 
below 40°F [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 manager should be consulted for the 
antifreeze best suited to your area. Freeze protection 
should be maintained to 15°F [9°C] below the lowest 
expected entering loop temperature. For example, if 
30°F [-1°C] is the minimum expected entering loop 
temperature, the leaving loop temperature would be 25 to 
22°F [-4 to -6°C] and freeze protection should be at 15°F 
[-10°C].  Calculation is as follows:
30°F - 15°F = 15°F [-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 fluid in the piping system. 
Then use the percentage by volume shown in Table 
1 for the amount of antifreeze needed. Antifreeze 
concentration should be checked from a well mixed 
sample using a hydrometer to measure specific gravity.
Table 1: Approximate Fluid Volume (gal.) 
per 100' of Pipe
Fluid Volume (gal [L]/100’ Pipe)
Pipe
Size
Volume (gal) [L]
Copper
1”
4.1 [15.5]
1.25”
6.4 [24.2]
2.5”
9.2 [34.8]
Rubber Hose 
1”
3.9 [14.8]
Polyethylene
3/4” IPS SDR11
2.8 [10.6]
1” IPS SDR11
4.5 [17.0]
1.25” IPS SDR11
8.0 [30.3]
1.5” IPS SDR11
10.9 [41.3]
2” IPS SDR11
18.0 [68.1]
1.25” IPS SCH40
8.3 [31.4]
1.5” IPS SCH40
10.9 [41.3]
2” IPS SCH40
17.0 [64.4]
Unit Heat Exchanger
Typical
1.0 [3.8]
Flush Cart Tank
10” Dia x 3ft 
[254mm x 0.9m]
10 [37.9]
DXM2 Control