Lennox AIRCOOLAIR KNCK 24E Installation, Operation & Maintenance Manual page 16

PRECAUTIONS TO BE TAKEN IN THE USE OF R-407C Refrigerant:
R-407C Refrigerant is used in the unit; therefore, the following precautions characteristic of this gas
should be taken:
- The Vacuum Pump must have a Check Valve or Solenoid Valve.
- Pressure Gauges and Hoses for the exclusive use with R-407C Refrigerant should be used.
- The charge should be carried out in the Liquid Phase.
- Always use scales to weight-in charge
- Use the Leak Detector exclusive for R-407C Refrigerant.
- Do not use mineral oil, only synthetic oil to ream, expand or make connections.
- Keep pipes wrapped before using them and be very thorough about any possible dirt (dust, filings,
burrs, etc.).
- When there is a leak, gather what is left of the charge, create a vacuum in the unit and completely
recharge with new R-407C Refrigerant.
- Brazing should always be carried out in a nitrogen atmosphere.
- Reamers should always be well sharpened.
TABLE 2: CHARGE OF REFRIGERANT R-407C PER METER OF COPPER LINE
MODEL 24E
MODEL 32E
MODEL 38E
MODEL 43E
MODELS 48D / D2
MODELS 64D / D2
MODELS 76D / D2
MODELS 86D / D2
NOTE:
As an option