Daikin RXYTQ20U7YF [88/152] Charging refrigerant

18 | Piping installation

Installer and user reference guide

RXYTQ8~16U7YF

VRV IV+ heat pump for high ambient temperatures

4P561157-1A – 2020.10

▪ Make sure to insulate the connection piping and refrigerant branch kits entirely.

▪ Be sure to insulate the liquid and gas piping (for all units).

▪ Use heat resistant polyethylene foam which can withstand a temperature of 70°C

for liquid piping and polyethylene foam which can withstand a temperature of

120°C for gas piping.

▪ Reinforce the insulation on the refrigerant piping according to the installation

environment.

Ambient temperature Humidity Minimum thickness

≤30°C 75% to 80% RH 15mm

>30°C ≥80% RH 20mm

▪ If there is a possibility that condensation on the stop valve might drip down into

the indoor unit through gaps in the insulation and piping because the outdoor

unit is located higher than the indoor unit, this must be prevented by sealing up

the connections. See below figure.

a Insulation material

b Caulking etc.

18.4 Charging refrigerant

18.4.1 Precautions when charging refrigerant

WARNING

▪ ONLY use R410A as refrigerant. Other substances may cause explosions and

accidents.

▪ R410A contains fluorinated greenhouse gases. Its global warming potential (GWP)

value is 2087.5. Do NOT vent these gases into the atmosphere.

▪ When charging refrigerant, ALWAYS use protective gloves and safety glasses.

NOTICE

If the power of some units is turned off, the charging procedure cannot be finished

properly.

NOTICE

In case of a multiple outdoor system, turn on the power of all outdoor units.

NOTICE

Be sure to turn ON the power 6 hours before operation in order to have power

running to the crankcase heater and to protect the compressor.