Refrigerant Piping Work - Daikin RXN15KEVJU Installation Manual

Outdoor Unit Installation
6.
Refi lling the refrigerant
Check the type of refrigerant to be used on the machine nameplate.
Precautions when adding R410A
Fill from the liquid pipe in liquid form.
It is a mixed refrigerant, so adding it in gas form may cause the refrigerant composition to change, preventing normal operation.
1) Before fi lling, check whether the cylinder has a siphon attached or not. (It should have something like "liquid fi lling
siphon attached" displayed on it.)
Filling a cylinder with an attached siphon
Stand the cylinder upright when
filling.
There is a siphon pipe inside, so the
cylinder need not be upside-down to
fill with liquid.
• Be sure to use the R410A tools to ensure pressure and to prevent foreign objects entering.
7.

Refrigerant piping work

7-1 Caution on pipe handling
1) Protect the open end of the pipe against dust and moisture.
2) All pipe bends should be as gentle as possible. Use a pipe bender for
bending.
7-2 Selection of copper and heat insulation materials
When using commercial copper pipes and fi ttings, observe the following:
1) Insulation material: Polyethylene foam
Heat transfer rate: 0.041 to 0.052W/mK (0.024 to 0.030Btu/fth°F (0.035 to 0.045kcal/mh°C))
Refrigerant gas pipe's surface temperature reaches 230°F (110°C) max.
Choose heat insulation materials that will withstand this temperature.
2) Be sure to insulate both the gas and liquid piping and to provide insulation
dimensions as below.
Gas side
O.D. 1/2 inch
(12.7mm)
Minimum bend radius
1-9/16 inch (40mm)
or more
Thickness 0.031 inch (0.8mm) (C1220T-O)
• Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
8
Gas pipe thermal
Liquid side
insulation
O.D. 1/4 inch I.D. 0.551-0.630 inch
(6.4mm) (14-16mm)
Thickness 0.393 inch (10mm) Min.
1-3/16 inch (30mm)
or more
Filling other cylinders
Turn the cylinder upside-down
when filling.
Rain
If no flare cap is
available, cover
the flare mouth
with tape to keep
dirt or water out.
Gas pipe
Liquid pipe thermal
insulation
I.D. 0.315-0.393 inch
(8-10mm)
Gas pipe
insulation
Wall
Be sure to
place a cap.
Inter-unit wire
Liquid pipe
Liquid pipe
insulation
Finishing tape
Drain hose
English