6. Piping installation
Installer reference guide / Mono tank integrated type
74
Unit resistance and PHE resistance by glycol concentrate
The unit is composed of water pipes and PHE basically.
To ensure correct operation and predict the expected performance, Flow and Resistance table can be used and Flow and
resistance characteristic is dependent on Glycol concentration.
LPM
AE080BXYD**
AE050RXYDEG/AE080RXYD**
AE120BXYD**/AE140BXYD**
AE120RXYD**/AE160RXYD**
LPM
kPa
kPa
0
0
0
0
10
10
10
10
20
20
30
30
40
40
50
50
60
60
70
70
15
15
20
20
25
25
30
30
35
35
40
40
45
45
50
50 55 60 65 70
WATER
PG 10%
PG 20%
PG 30%
PG 40%
PG 45%
Changing Glycol concentration can cause the pressure drop of the system and it can lead to make flow rate slow.
Just in case performance degradation, installer shall be careful of flow rate changes.
The required concentration of glycol depends on the lowest expected outdoor temperature, and on whether you want to
protect the system from bursting or from freezing. To prevent the system from freezing, more glycol is required.
Add glycol according to the table below
Freezing Points of Propylene Glycol - Water Mixtures
Percent Propylene Glycol [wt.%]
Freezing Point [℉]
Freezing Point [℃]
0
32
0
10
26
-3
20
20
-7
30
10
-12
36
0
-18
40
-5
-20
43
-10
-23
48
-20
-29
Freezing protection: Anti freeze valves
In order to prevent system water from freezing inside the pipework during subzero ambient conditions after sudden
power outage, anti freeze valves are advised if glycol is not a suitable solution.
An anti freeze valve opens when the medium (water) is below a certain low temperature value.
When using the EHS for cooling in summertime, an anti freeze valve with ambient sensor is required to avoid unwanted
opening due to low water temperatures.