Mitsubishi Electric ECOV-X37VA Manuel D'installation page 26

7-1-3. Pipe size
Select the size of the suction pipe and liquid pipe according to the diameter of the connection port of the condensing unit,
not of the evaporator.
Select the size of the suction pipe in consideration of oil return and pressure loss.
Model Suction pipe [mm (in)] Liquid pipe [mm (in)]
ECOV-X37VA
ECOV-X55VA
The pipe sizes shown above are standard pipe sizes.
The design pressure of the liquid pipe and the suction pipe is 8.0 MPa. Use pipes that can withstand the above design pres-
sure.
For ECOV-X55VA, when the pipe length is 30 m or longer, use a liquid pipe having a diameter of one size larger.
7-1-4. Height difference between devices
When the unit is installed in a high place, ensure there is enough space for transporting a heavy load such as a refrigerant
cylinder during servicing or test runs, and install the service valve at the most appropriate place for servicing.
Loop for preventing the
liquid backflow while the
unit is stopped
Suction pipe
Liquid pipe
Unit
Insulate the en-
tire length of the
suction pipe.
Service valve
(Fully open except for servicing)
Sight glass
Dryer Downward inclination (1/200
Safety valve
to 1/250) toward the unit
7-1-5. Supporting the pipes
Support the pipes in proper distance. Install a bent pipe or a slide valve (horizontal loop) to absorb expansion and contraction
of the pipes that is caused by temperature fluctuation.
7-1-6. Notes on contaminants while flaring the pipes
Follow the instructions below to prevent abrasive components contained in sandpaper and cutting tools from entering the
refrigerant circuit because those components can cause failures of the compressor and valves.
• To deburr pipes, use a reamer or other deburring tools, not sandpaper.
• To cut pipes, use a pipe cutter, not a grinder or other tools that use abrasive materials.
• When cutting or deburring pipes, do not allow cutting chips or other foreign matters to enter the pipes.
• If cutting chips or other foreign matters enter pipes, wipe them off the inside of the pipes.
Purge the pipes of dust with nitrogen gas or dry air before connecting the pipes. (Do not use the tools that generate a large
amount of shaving particles, such as saw and grind stone.)
7-2. Installation of suction pipe
7-2-1. Installing the horizontal pipe
Install the horizontal pipe in such a way that it has a downward inclination (at least 1/200) towards the unit.
WT09614X03_GB
ø15.88 (5/8) ø9.52 (3/8)
ø15.88 (5/8) ø9.52 (3/8)
Solenoid valve <liquid> must
be attached closer to the ex-
pansion valve than the unit.
Evaporator
S
Trap for preventing liquid
accumulation in the tem-
perature sensing valve
Strainer
Insulate the entire
length of the liquid pipe.
Service valve
Unit
(Fully open except for servicing)
Sight glass
Dryer
Safety valve
Insulate the en-
Loop for pre-
tire length of
venting the liquid
the liquid pipe.
backflow while
the unit is
stopped
S
Evaporator
Strainer
Trap for preventing liquid ac-
cumulation in the tempera-
Solenoid valve <liquid> must be attached
ture sensing valve
closer to the expansion valve than the unit.
26
Suction pipe
Liquid pipe
Insulate the entire length
of the suction pipe.
Flow rate at least 6 m/s
Oil return trap