CLIVET WSAN-YMi 101, Instruction Manual For Installation, Use And Maintenance, Page: 24 / 128

Ethylene Glycol
Ice formation can cause damage to the hydraulic system. As the outdoor unit may be exposed to sub-zero temperatures, care must be
taken to prevent freezing of the system.
All internal hydronic parts are insulated to reduce heat loss. Insulation must also be added to the field piping.

The software contains special functions using the heat pump to protect the entire system against freezing. When the temperature
of the water flow in the system drops to a certain value, the unit will heat the water, either using the heat pump, the electric heating
tap, or the backup heater. The freeze protection function will turn off only when the temperature increases to a certain value.
In event of a power failure, the above features would not protect the unit from freezing.
Since a power failure could happen when the unit is unattended,the recommends use anti-freeze fluid to the water system.
Depending on the expected lowest outdoor temperature, make sure the water system is filled with a concentration of glycol as
mentioned in the table below.
When glycol is added to the system, the performance of the unit will be affected.
The correction factor of the unit capacity, flow rate and pressure drop of the system is listed in the table below.
Quality of
glycol/%
Modification coefficient
Freezing point/°C
Cooling capacity
modification
Power
modification
Water
resistance
Water flow
modification
0 1.000 1.000 1.000 1.000 0
10 0.984 0.998 1.118 1.019 -5
20 0.973 0.995 1.268 1.051 -15
30 0.965 0.992 1.482 1.092 -25
Propylene Glycol
If no glycol is added, the water must be drained out when there is a power failure.
Water may enter into the flow switch and cannot be drained out and may freeze when the temperature is low enough.
The flow switch should be removed and dried, then can be reinstalled in the unit.
WARNING
Ethylene Glycol and Propylene Glycol are TOXIC
The concentrations mentioned in the table above will not prevent freezing, but will prevent the hydraulics from bursting.
Quality of gly-
col/%
Modification coefficient
Freezing point/°C
Cooling capacity
modification
Power
modification
Water
resistance
Water flow
modification
0 1.000 1.000 1.000 1.000 0
10 0.976 0.996 1.071 1.000 -4
20 0.961 0.992 1.189 1.016 -12
30 0.948 0.988 1.380 1.034 -20