Danfoss R401A, R401B, R409A, R409B, R134a Installation guide
Service on Household
Compressors
Refrigerators and Freezers
Using New Refrigerants
April 1996 CN.73.C3.02 1
Replaces CN.73.C2.02
1.0 Introduction
1.1 Blends
(mixtures of HFC)
1.2 R134a (HFC)
1.3 R600a (Hydrocarbon)
2.0 General
Within a foreseeable future , CFC refrigerants will become unobtainable . This is a situation that will
effect the service possibilities on R12 systems in household appliances. In new production of
household appliances R12 will be replaced by R134a or R600a.
Please note that this guide excludes service on commercial appliances.
Since the introduction of R134a, several “transitional substances” have appeared. They have a
low ODP number and are intended for service only.
These refrigerants are interesting because they do not presuppose the use of polyolester oil.
To ensure a satisfactory miscibility between refrigerant and oil, the application of R134a refrigerant
presupposes the use of an R134a compressor charged with polyolester (POE).
This will complicate the future servicing when R12 refrigeration systems are to be changed over to
R134a refrigerant, as it is difficult to prevent contamination b y residues of the original refrigeration
oil, typically mineral oil or alkyl benzene.
The presence of residual mineral oil or alkyl benzene is unfortunate because it does not become
part of the R134a/POE mixture but circulates independently through the system. The eff ect can be
negative if the system contains “oil pockets”. After some time, the oil circulating in the system can
collect in quantities which pass through the capillary tube relatively slowly. This will effect the
refrigerant injection into the evaporator momentarily.
This refrigerant is flammable and only allowed for use in appliances which fulfil the safety requirements laid down in amendment TS 95006 to IEC 335 - 2 - 24 (To cover potential risk originated
from the use of flamable refrigerants).
In principle there is no need to replace the refrigerant in operational hermetic refrigeration systems. Neither is there any point in replacing refrigerant when servicing, provided that the original
refrigerant is available either as new or reclaimed. A precondition here is of course that the legislation of the country concerned is not restrictive in this respect.
Changing over to an alternative refrigerant is not without problems. Close consideration should be
given to the economic justification of proceeding with the task. It is also appropriate to find out just
what the user expects in terms of the operation and lifetime of the repaired system.
The choice of refrigerant for servicing R12 systems is between the transitional substances (blends)
or R134a.
Among the refrigerant mixtures offered are R401A and R401B which are marketed by DuPont.
These blends are ternary mixtures (non-azeotropes) made of three single components, R22, R152a,
and R124. Corresponding mixtures are also marketed by Atochem, R409A (Forane FX 56) and
R409B (Forane FX57). They are based on the components R22, R142B, and R124 (table 1). The
mixtures are interesting because they do not presuppose the use of polyolester compressor oil.
They have a low ODP number and can be used for service when R12 refrigerant is prohibited.
ASHRAE
No.
R401A R22 - R152a - R124 53 - 13 - 34 Suwa MP39 0.03 0.22 6.4 Alkyl benzene
R401B R22 - R152a - R124 61 - 11 - 28 Suwa MP66 0.035 0.24 6.0 Alkyl benzene
R409A R22 - R142B - R124 60 - 15 - 25 Forane FX56 0.05 0.31 8.1 Alkyl benzene
R409B R22 - R142B - R124 65 - 10 - 25 Forane FX57 0.05 0.31 7.2 Alkyl benzene
R134a 0.0 0.28 0.0 Ester oil
Table 1. Refrigerants for servicing R12 systems
Components Composition%Trade name ODP GWP Temp.
glide
Oil type
2 CN.73.C3.02 April 1996
2.1 Servicing with blends The blends mentioned can be used for servicing, provided the following rules are observed,
The original compressor can be used, provided that it is intact. But the compressor oil must
be of the type alkyl benzene.
If the original compressor contains mineral oil it has to be changed to alkyl benzene. The
alkyl benzene must have more or less the same viscosity as the original oil.
A viscosity of about 30 cSt is a suitable choice for household refrigeration compressors.
Table 2 shows the oil types used in Danfoss compressors.
Compressor type Compressor
V
TL-A 115 2 - 4 Synthetic Unchanged
TL-A 220 2 - 4 Mineral Alkyl benzene
TL-A 220 5 Synthetic Unchanged
TLS-A 220 4 Mineral Alkyl benzene
TLS-A 220 5 Synthetic Unchanged
TLES-A 220 4 Mineral Alkyl benzene
TLES-A 220 5 Synthetic Unchanged
TFS-A 115 4 - 5 Synthetic Unchanged
TFS-AT 220 4 - 5 Synthetic Unchanged
TF-B 115 4 Synthetic Unchanged
TL-B 220 2.5 - 3 Mineral Alkyl benzene
TL-B 220 4 Synthetic Alkyl benzene
NLE-A 115 6 - 7 Synthetic Unchanged
NF-A 115 6 Synthetic Unchanged
NL-A 220 6 - 7 Mineral Alkyl benzene
NLE-A 230 6 - 7 Mineral Alkyl benzene
FR-A 115 7.5 - 8.5 Mineral Alkyl benzene
FR-A 220 7.5 - 10 Mineral Alkyl benzene
FR-A 220 11 V-Oil 7041 Unchanged
FF-AT 220 6 - 10 Mineral Alkyl benzene
FFS-A 115 7 - 9 Mineral Alkyl benzene
FF-BK 115 6.5 - 8.5 Mineral Alkyl benzene
FF-BX 115 6.5 - 8.5 Mineral Alkyl benzene
FR-B 220 6 - 11 Mineral Alkyl benzene
FR-H 220 7 V-Oil 7041 Unchanged
SC-A 115 12 - 15 Mineral Alkyl benzene
SC-A 220 12 - 15 Mineral Alkyl benzene
SC-A 220 18 - 21 V-Oil 7041 Unchanged
SC-AA 240 15 V-Oil 7041 Unchanged
SC-B 115/220 10 - 2 1 V-Oil 7041 Unchanged
SC-H 220 10 - 15 V-Oil 7041 Unchanged
SC-HH 220 10 - 15 V-Oil 7041 Unchanged
displacement
3
cm
Present oil type Oil type for blendVoltage
Table 2. Oil types
If the original compressor is defective, the choice is between an R12 compressor and an R134a
compressor. The refrigeration capacity should be about the same as that of the original compressor. The R12 compressor oil must be changed over to alkyl benzene oil, provided that the original
oil charge was mineral oil. The R134a compressor can be used directly charged with polyolester
oil.
The filter drier must always be replaced. The new filter drier must contain a desiccant of the type
XH9 (UOP) or Siliporite H3R (CECA)
The system components, especially the evaporator, will always contain some oil transferred from
the original compressor. This is not critical if the new compressor contains alkyl benzene. But if a
compressor containing polyolester is to be used, residues in the original oil must be kept to the
lowest possible.
April 1996 CN.73.C3.02 3
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