Danfoss R134a User Manual

Operating conditions
SM084 to 185
SY185 to 380
R22
Motor supply SM / SY / SZ scroll compressors can be operated
at nominal voltages as indicated on “Motor
voltage code” section. Under-voltage and over-
voltage operation is allowed within the indicated
voltage ranges. In case of risk of under-voltage
operation, special attention must be paid to
current draw.
The operating envelopes for SM / SY / SZ
scroll compressors are given in the gures
below, where the condensing and evaporating
temperatures represent the range for steady-
state operation. Under transient conditions, such
as start-up and defrost, the compressor may
operate outside this envelope for short periods.
The gures below show the operating envelopes
for refrigerants R22, R407C, R134a, R404A, R507
and R513A.
The operating limits serve to dene the
envelope within which reliable operations of the
compressor are guaranteed:
• Maximum discharge gas temperature: +135°C
• A suction superheat below 5 K (10 K for R407C)
is not recommended due to the risk of liquid
ood back
• Maximum superheat of 30 K
• Minimum and maximum evaporating and
condensing temperatures as per the operating
envelopes.
SM / SY / SZ compressors can be applied from
-35°C to +63°C (for SM/SZ084 to 185) and +53°C
(for SY/SZ 240 to 380) ambient temperature. The
compressors are designed as 100 % suction gas
cooled without need for additional fan cooling.
Ambient temperature has very little eect on the
compressor performance.
In case of enclosed tting and high ambient
temperature it’s recommend to check the
temperature of power wires and conformity to
their insulation specication.
In case of safe tripping by the compressor
overload protection the compressor must cool
down to about 60°C before the overload will
reset. A high ambient temperature can strongly
delay this cool-down process.
Although the compressor itself can withstand
low ambient temperature, the system may
require specic design features to ensure safe
and reliable operation. See section ‘Specic
application recommendations’.
Application envelope at
dew temperatures
Compressor ambient
temperature
High ambient temperature
Low ambient temperature
70
65
60
55
50
45
40
35
30
-25 -20 -15 -10
-5
0 5 10 15 20
Condensing temperature (°C)
Evaporating temperature (°C)
S.H. = 30 K
SUPERHEAT
S.H. = 11.1 K
S.H. = 5 K
26 AB237986441643en-010801
Application Guidelines

Danfoss R134a Specifications

General

Brand	Danfoss
Model	R134a
Category	Air Compressor
Language	English