Bard Wall Mounted Package Air Conditioners W12A2-A - Manual (Page 13)

Manual 2100-509E
Page 13 of 17
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THESE UNITS REQUIRE R-410A
REFRIGERANT AND POLYOL
ESTER OIL.
GENERAL:
1. Use separate service equipment to avoid cross
contamination of oil and refrigerants.
2. Use recovery equipment rated for R-410A
refrigerant.
3. Use manifold gauges rated for R-410A (800 psi/250
psi low).
4. R-410A is a binary blend of HFC-32 and HFC-125.
5. R-410A is nearly azeotropic - similar to R-22 and
R-12. Although nearly azeotropic, charge with
liquid refrigerant.
6. R-410A operates at 40-70% higher pressure than
R-22, and systems designed for R-22 cannot
withstand this higher pressure.
7. R-410A has an ozone depletion potential of zero,
but must be reclaimed due to its global warming
potential.
8. R-410A compressors use Polyol Ester oil.
9. Polyol Ester oil is hygroscopic; it will rapidly absorb
moisture and strongly hold this moisture in the oil.
10. A liquid line dryer must be used - even a deep
vacuum will not separate moisture from the oil.
11. Limit atmospheric exposure to 15 minutes.
12. If compressor removal is necessary, always plug
compressor immediately after removal. Purge with
small amount of nitrogen when inserting plugs.
TOPPING OFF SYSTEM CHARGE
If a leak has occurred in the system, Bard Manufacturing
recommends reclaiming, evacuating (see criteria above),
and charging to the nameplate charge. If done correctly,
topping off the system charge can be done without
problems.
With R-410A, there are no significant changes in the
refrigerant composition during multiple leaks and
recharges. R-410A refrigerant is close to being an
azeotropic blend (it behaves like a pure compound or
single component refrigerant). The remaining refrigerant
charge, in the system, may be used after leaks have
occurred and then “top-off” the charge by utilizing the
pressure charts on the inner control panel cover as a
guideline.
REMEMBER: When adding R-410A refrigerant, it must
come out of the charging cylinder/tank as a liquid to
avoid any fractionation, and to insure optimal system
performance. Refer to instructions for the cylinder that
is being utilized for proper method of liquid extraction.
SAFETY PRACTICES:
1. Never mix R-410A with other refrigerants.
2. Use gloves and safety glasses, Polyol Ester oils can
be irritating to the skin, and liquid refrigerant will
freeze the skin.
3. Never use air and R-410A to leak check; the
mixture may become flammable.
4. Do not inhale R-410A – the vapor attacks the
nervous system, creating dizziness, loss of
coordination and slurred speech. Cardiac
irregularities, unconsciousness and ultimate death
can result from breathing this concentration.
5. Do not burn R-410A. This decomposition
produces hazardous vapors. Evacuate the area if
exposed.
6. Use only cylinders rated DOT4BA/4BW 400.
7. Never fill cylinders over 80% of total capacity.
8. Store cylinders in a cool area, out of direct
sunlight.
9. Never heat cylinders above 125°F.
10. Never trap liquid R-410A in manifold sets, gauge
lines or cylinders. R-410A expands significantly at
warmer temperatures. Once a cylinder or line is full
of liquid, any further rise in temperature will
cause it to burst.
WARNING
Failure to conform to these practices
could lead to damage, injury or death.