Specifications
45
This option allows production of brine down to -10°C. The
unit is equipped with reinforced evaporator insulation as
well as suction pipe insulation.
The operating range is a function of the suction pressure,
which in turn is a function of:
- the brine type,
- the brine concentration,
- the flow rate,
- the brine temperature,
- the condensing pressure (ambient temperature).
Example: For operation with propylene glycol at 40% and a
brine temperature of -10°C (entering temperature -5°C), the
maximum ambient operating temperature will be around 38°C.
With propylene glycol at 40%
To find out the operating limits for each unit, based on the
brine type and the brine concentration, please refer to the
selection software.
The evaporator low pressure and frost protection depends
on the amount of antifreeze added to the water circuit
(evaporator approach as well as frost protection are based
on this amount).
It is therefore essential to control the amount of antifreeze
in the water loop at the first start-up (circulate for 30 minutes
to ensure good homogeneity of the mixture before taking
the sample). Refer to the manufacturer’s data to define the
frost protection, based on the concentration rate measured.
The frost protection value (temperature) must be used in
the unit software parameters (see Carrier Service Guide).
This value will allow the definition of the following limits:
1. Evaporator frost protection
2. Low pressure protection
It is recommended that the commissioning of a brine system
is done by Carrier.
For information: The protection values given by our supplier,
based on the antifreeze solutions used in the Carrier
Montluel laboratory, are as follows: (these values can change
for different suppliers).
10 -3.8 10 -2.6
15 -6.1 15 -4.3
20 -8.8 20 -6.6
25 -11.8 25 -9.6
30 -15.2 30 -13
35 -19.1 35 -16.7
40 -23.6 40 -20.7
45 -29 45 -25.3
Based on the table above, if the ethylene glycol concentration
by weight in the water loop is 35% the value of -19.1°C
must be used in the software.
It is essential to carry out an annual check (minimum) of the
amount of glycol, and adjust the frost protection value in
the software based on the rate measured. This procedure
must be systematic, if water or antifreeze solution is added.
If the antifreeze concentration exceeds 30%, it is recom-
mended to reduce the brine flow rate to prevent over-
loading and over-heating of the motor.
The flow rate limits are given in the table below:
For an application between 32 and 40% and operation at
an outside air temperature between 40 and 48°C use linear
interpolation.
IMPORTANT: Never use a glycol concentration of less
than 20%, as the brine will become aggressive and there
will be an increased risk of corrosion of the cast iron
parts of the hydronic kit.
Leaving water temperature, °C
Outside air temperature, °C
Max. flow rate with clear water l/s
Ambienttemperature=48°C 14.7 14.7 14.7 14.7 14.7 18.9 18.9 24.4 24.4 24.4 29.4 29.4
(L/J) RL (L/J) RL (L/J) RL (L/J) RL (L/J) RL (L/J) RL (L/J) RL (L/J) RL (L/J) RL (L/J) RL (L/J) RN (L/J) RN
206 206 206 206 206 206 206 208 208 208 208 208
11/2.2 11/2.2 11/2.2 11/2.2 11/2.2 11/3 11/3 12/4 12/4 12/4 13/5.5 13/5.5
Max. flow rate, 40% antifreeze l/s
Ambienttemperature=40°C 12.8 12.8 12.8 12.8 12.8 17.8 17.8 18.9 18.9 18.9 21.7 21.7
Ambienttemperature=48°C 11.9 11.9 11.9 11.9 11.9 15.3 15.3 16.9 16.9 16.9 20.0 20.0
(L/J) RL (L/J) RL (L/J) RL (L/J) RN (L/J) RN (L/J) RN (L/J) RN (L/J) RN (L/J) RN (L/J) RN (S/D) IL (S/D) IL
206 206 206 205 205 206 206 206 206 206 206 206
14/4 14/4 14/4 14/4 14/4 15/5.5 15/5.5 18/7.5 18/7.5 18/7.5 19/11 19/11
Max. flow rate, 40% antifreeze l/s
Ambienttemperature=40°C 13 13 13 11.7 11.7 17.2 17.2 21.7 21.7 21.7 26.1 26.1
Ambienttemperature=48°C 12.5 12.5 12.5 11.1 11.1 16.1 16.1 20.0 20.0 20.0 24.2 24.2
48°C
46°C
38°C
-10°C
0°C
3°C