Water Heater Frost Protection; Frost Protection Of The Heat Exchanger; Airflow Measurement - Change Of Coefficient K (Only Operation Mode Cav) - S&P CADB/T-N PRO-REG Instrucciones De Uso

13. WATER HEATER FROST PROTECTION

In models with Water Heater, the temperature of the water return is continually supervised by a probe,
in order to prevent it to freeze.
In case water temperature drops below 12°C, the water valve starts to open (if it already wasn't) and
Frost Risk alarm is activated.
If water temperature falls below 7°C, then fans are stopped and the alarm Water temp too low, system
off is activated. Till the temperature is not over 7°C, the unit will not turn on again.
Unit in OFF mode
When the unit is OFF, antifrost protection remains active trying to maintain a constant return water
temperature of 25°C.

14. FROST PROTECTION OF THE HEAT EXCHANGER

In case the exhaust air temperature drops below 5°C, the bypass will open to prevent the freezing of
the exchanger.
In the case that the inlet temperature (Outdoor air) goes down to -7ºC, the supply fan will stop.
15. AIRFLOW MEASUREMENT – CHANGE OF COEFFICIENT K (only operation mode CAV)
In order to obtain the actual fl ow by means of the pressure transmitter, the parameter K has to be
defi ned. It depends on the Heat Recovery Unit model as showed in the following table:
Model Coeffi cient K
CADB-N 05
CADB-N 08
CADB-N 18
CADB-N 30
CADT-N 45
CADT-N 55
CADT-N 80
58
60
84
131
104
207
252
63