Service Manual
6
Use a vacuum pump with a reverse ow check
valve.
Vacuum pump oil may ow back into refrigerant cycle and
that can cause deterioration of refrigerant oil, etc.
Use the following tools specically designed for
use with R410A refrigerant.
The following tools are necessary to use R410A refrigerant.
Tools for R410A
Gauge manifold Flare tool
Charge hose Size adjustment gauge
Gas leak detector Vacuum pump adaptor
Torque wrench Electronic refrigerant
charging scale
Handle tools with care.
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
Use the specied refrigerant only.
Never use any refrigerant other than that specied.
Doing so may cause a burst, an explosion, or re when the
unit is being used, serviced, or disposed of.
Correct refrigerant is specied in the manuals and on the
spec labels provided with our products.
We will not be held responsible for mechanical failure,
system malfunction, unit breakdown or accidents caused
by failure to follow the instructions.
Do not use a charging cylinder.
If a charging cylinder is used, the composition of refriger-
ant will change and the eciency will be lowered.
Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a ame, poisonous gases will be released.
Cautions for units utilizing refrigerant R410A
2-2. CAUTIONS RELATED TO R410A REFRIGERANT
Make sure that the inside and outside of refriger-
ant piping is clean and it has no contaminants
such as sulfur, oxides, dirt, shaving particles, etc.,
which are hazard to refrigerant cycle.
In addition, use pipes with specied thickness.
Contamination inside refrigerant piping can cause deterio-
ration of refrigerant oil, etc.
Store the piping indoors, and keep both ends of
the piping sealed until just before brazing.
(Leave elbow joints, etc. in their packaging.)
If dirt, dust or moisture enters into refrigerant cycle, that can cause
deterioration of refrigerant oil or malfunction of compressor.
The refrigerant oil applied to are and ange
connections must be ester oil, ether oil or
alkylbenzene oil in a small amount.
If large amount of mineral oil enters, that can cause deterio-
ration of refrigerant oil, etc.
Charge refrigerant from liquid phase of gas
cylinder.
If the refrigerant is charged from gas phase, composition
change may occur in refrigerant and the eciency will be
lowered.
Do not use refrigerant other than R410A.
If other refrigerant (R22, etc.) is used, chlorine in refrigerant
can cause deterioration of refrigerant oil, etc.
OBH702H