The Kipp & Zonen CNR 4 net radiometer is produced as the standard instrument or with an integrated ventilation unit and heater.
The CNF 4 ventilation unit can also be bought as a kit for retro-fitting to a CNR 4 that was purchased without it. CNF 4 provides a clean air flow over all four of the CNR 4 radiometer domes and windows and is designed to operate under all weather conditions. The only part that needs maintenance is the air inlet filter, which should be checked at regular intervals and cleaned or replaced when necessary.
The integrated 10 W heating can be switched on by the operator when required. This raises the temperature of the domes and windows slightly above ambient to prevent the formation of dew and frost and to disperse precipitation. The ventilation fan and heater run from 12 VDC and can be operated by the accessory CVP 2 universal AC-DC power adaptor.
