3
You should consult the original equipment manufac-
turer for recommendations concerning the compat-
ibility of elastomers and plastics used in their system
and the new refrigerant. Although many system
components used with CFCs are also compatible
with Suva
®
refrigerants, there are exceptions that, if
not replaced, can cause refrigerant leakage or sys-
tem failure.
Field experience has shown that some systems
retrofitted directly from R-502 to Suva
®
HP62
or Suva
®
507 can have increased leakage due to
shrinkage of elastomers (o-rings, gaskets) follow-
ing removal of the R-502. This same situation
might exist in an R-22 retrofit. Replacement of
these elastomers may add additional cost and
time to the retrofit.
Retrofits of R-12 or R-502 systems with other alter-
native refrigerants such as HCFC-22 may require
more extensive modifications to the existing equip-
ment, such as replacement of the compressor with
multistage compressors or use of liquid injection.
For some systems this additional cost may be large.
Suva
®
refrigerants provide the service contractor
and equipment owner with a cost-effective way to
retrofit an existing system.
Note: Suva
®
refrigerants were not designed for use
in conjunction with other refrigerants or additives
that have not been clearly specified by DuPont or
the equipment manufacturer. Mixing Suva
®
refriger-
ants with other refrigerants, may have an adverse
effect on system performance. “Topping off” a
different refrigerant with any Suva
®
refrigerant is
not recommended.
Refrigerant Recovery Information
Most recovery or recycle equipment used for R-12,
R-502, or R-22 can be used for Suva
®
refrigerants.
Use standard procedures to avoid cross-contamina-
tion when switching from one refrigerant to another.
Consult the equipment manufacturer for specific
recommendations.
In the United States, DuPont will take back for
reclaim the Suva
®
refrigerants discussed in this
bulletin.
What to Expect Following a Retrofit
These tables show approximate system performance
changes following a retrofit. These values are gen-
eral guidelines for system behavior, and actual per-
formance will vary with each system.
Suva
®
134a is compared to R-12, Suva
®
HP62 and
Suva
®
507 are compared to R-502.
Disch. Suct. Disch. Refrig.
Suva
®
Press. Press. Temp. Cap’y.
Refrig. psi (kPa) psi (kPa) °F (°C) (%)
134a +10 –2 –10 –10
(69.8) (–13.8) (–5.6)
HP62 +20 Same –10 Same
(+137.9) (–5.6)
507 +30 Same –15 Same
(+206.8) (+8.3)
Suva
®
HP62 is compared to R-22 (evap. temp. =
0°F [–18°C]). Note: Suva
®
507 provides perfor-
mance very similar to HP62.
Disch. Suct. Compression Disch. Refrig.
Suva
®
Press. Press. Ratio Temp. Cap’y.
Refrig. psi (kPa) psi (kPa) (%) °F (°C) (%)
HP62 +45 +10 –5 –64 +6
(+310) (+69.8) (–36)
How to read these tables
Example: R-12 to Suva
®
134a retrofit. Discharge pressure
with 134a will be in the range of 10 psig higher than R-12
(using discharge pressure column above).
