Danfoss EVRS 3-20, EVRST 10-20 Data sheet

Data Sheet

Solenoid valve
Type EVRS 3-20 and EVRST 10-20

Stainless steel solenoid valves used in liquid, suction, hot gas and oil return lines

EVRS and EVRST are valves made of stainless
steel.

• EVRS 3 is direct operated.

• EVRS 10, 15 and 20 are servo operated.

• EVRST 10,15 and 20 are forced servo
operated.

The valves are used in liquid, suction, hot gas
and oil return lines with ammonia or
uorinated refrigerants.

EVRS 3 and EVRST are designed for keeping
open at a pressure drop of 0 bar.

EVRS/EVRST 10, 15 and 20 are equipped with
spindel for manual opening.

EVRS and EVRST are supplied as components,
i.e. valve body and coil must be separately
ordered.

Features

• Stainless steel valve body and connections

• Max. working pressure 50 barg

• Applicable to HCFC, HFC, R717 (Ammonia)
and R744 (CO2)

• MOPD up to 38 bar with 20 watt a.c. coil

• Wide choice of a.c. and d.c. coils

• Designed for temperatures of media up to
105°C

• Manual stem on EVRS and EVRST 10, EVRST
15 and EVRST 20

• Classication: DNV, CRN, BV, EAC etc. To get
an updated list of certication on the
products please contact your local Danfoss
Sales Company.

72886419420en-000601

Danfoss

32F418.11.15

37

36

4
16

28
49

51

18
29

Danfoss

32F417.11.15

24

4

16

18

28

49

29

Danfoss

32F419.13.13

28

14

8

6

16

45

5

EVRST EVRS

53

44

49

29

83

84

73

45

43

28

16

4

82

80

18

40

Pg13.5

20

36

Danfoss

32F476.11.12

4.

16.

18.

20.

24.

28.

29.

36.

40.

43.

44.

45.

49.

51.

53.

73.

80.

82.

83.

84.

Coil

Armature

Pilot valve plate

Earth terminal

Connection for exible steel

hose

Gasket

Pilot orice

DIN plug

Terminal box

Valve cover

O-ring

Valve cover gasket

Valve body

Cover

Manual operating spindle

Equalization hole

Diaphragm

Support washer

Valve seat

Main valve plate

Solenoid valve, Type EVRS 3-20 and EVRST 10-20

Function

Figure 1: EVRS 3, pipe thread

Figure 3: EVRS / EVRST 10 and 15

Figure 2: EVRS 3, weld

Figure 4: EVRS / EVRST 20

The solenoid valve design is based on three dierent principles:

1.

Direct operation

2.

Servo operation

3.

Forced servo operation

1. Direct operation

EVRS 3 is directly operated. The valve opens direct for full ow when the armature (16) moves up into the magnetic
eld of the coil. This means that the valve operates with a min. dierential pressure of 0 bar. The valve plate (18)

made of teon and is tted direct to the armature (16).

Inlet pressure acts from above on the armature and with it the valve plate. Thus, inlet pressure, spring force and the
weight of the armature act to close the valve when the coil is currentless.

2. Servo operation

© Danfoss | Climate Solutions | 2021.03 72886419420en-000601 | 2

Solenoid valve, Type EVRS 3-20 and EVRST 10-20

EVRS 10, 15 and 20 are servo operated with a "oating" diaphragm (80). The pilot orice (29), which is of stainless
steel, is placed in the centre of the diaphragm. The teon pilot valve plate (18) is tted direct to the armature (16).
With the coil currentless, the main orice and pilot orice are closed. The pilot orice and main orice are held
closed by the weight of the armature, the armature spring force and the dierential pressure between inlet and
outlet sides.

When current is applied to the coil the armature is drawn up into the magnetic eld and opens the pilot orice. This
relieves the pressure above the diaphragm because the space above the diaphragm becomes connected to the
outlet side of the valve. The dierential pressure between inlet and outlet sides then presses the diaphragm away
from the main orice which opens to full ow. Thus a certain minimum dierential pressure is necessary to open the
valve and keep it open. For EVRS 10, 15 and 20 valves this dierential pressure is 0.05 bar. When current is switched
o, the pilot orice closes. Then the pressure above the diaphragm rises, via the equalization holes (73) in the
diaphragm, to the inlet pressure and causes the diaphragm to close the main orice.

3. Forced servo operation

EVRST 10, 15 and 20 are forced servo operated solenoid valves. Forced servo operation diers from servo operation
in that in a forced servo operated valve the armature and the diaphragm are connected by a spring. Thus the
armature helps to lift the diaphragm (80) and keep it lifted so that the pressure drop in the open valve is the least
possible. These types of valves therefore require no dierential pressure to keep them open.

© Danfoss | Climate Solutions | 2021.03 72886419420en-000601 | 3

Solenoid valve, Type EVRS 3-20 and EVRST 10-20

Media

Refrigerants

Applicable to HCFC, HFC, R717 (Ammonia) and R744 (CO2).

New refrigerants

Danfoss products are continually evaluated for use with new refrigerants depending on market requirements.

When a refrigerant is approved for use by Danfoss, it is added to the relevant portfolio, and the R number of the
refrigerant (e.g. R513A) will be added to the technical data of the code number. Therefore, products for specic
refrigerants are best checked at store.danfoss.com/en/, or by contacting your local Danfoss representative.

© Danfoss | Climate Solutions | 2021.03 72886419420en-000601 | 4

Type

Opening dierential pressure ∆p bar

kv value

(2)

m3/h

Max. working

pressure Ps

Min.

Max. (MOPD) liquid

(1)

10 W a.c.

12 W a.c.

20 W a.c.

20 W d.c.

EVRS 3

0.021253814

0.23

50 bar(g)

EVRS 10

0.0521253818

1.5

EVRST 10

0.014213816

1.5

EVRS 15

0.0521253818

2.7

EVRST 15

0.014213818

2.7

EVRS 20

0.0521253813

4.5

EVRST 20

0.014213813

4.5

Type

Rated capacity

(3)

kW

Liquid

Suction vapour

Hot gas

R717

R22

R134a

R404A

R410A

R717

R22

R134a

R404A

R410A

R717

R22

R134a

R404A

R410A

EVRS 3

21.8

4.6

4.3

3.2

4.5

6.5

2.1

1.7

1.7

2.3

EVRS/EVRST 10

142

30.2

27.8

21.1

29.793.4

2.5

3.1

4.3

42.6

13.91111.3

14.9

EVRS/EVRST 15

256

54.4

50.13853.5

16.1

6.2

4.4

5.5

7.7

76.7

24.9

19.8

20.3

26.7

EVRS/EVRST 20

426

90.6

83.5

63.3

89.1

26.9

10.3

7.3

9.212128

41.5

32.9

33.9

44.5

Type

R 744 Rated capacity kW

(4)

Liquid

Suction

EVRS 3

6.65

-

EVRS/ EVRST 10

43.3

6.9

EVRS/ EVRST 15

78

12.4

EVRS/ EVRST 20

130

20.7

Type

Liquid capacity Q

e

kW at pressure drop across valve ∆p bar

0.1

0.2

0.3

0.4

0.5

EVRS 3

17.8

25.1

30.8

35.6

39.8

EVRS/EVRST 10

116.0

164.0

201.0

232.0

259.0

EVRS/EVRST 15

209.0

295.0

362.0

418.0

467.0

EVRS/EVRST 20

348.0

492.0

603.0

696.0

778.0

Solenoid valve, Type EVRS 3-20 and EVRST 10-20

Product specication

Technical data

Temperature of medium

-40 °C / +105 °C for 10 or 12 watt coil. Max. 130 °C during defrosting. -40 °C / +80 °C for 20 watt coil.

Ambient temperature and enclosure for coil: See "Coils for solenoid valves", lit.no. AI237186440089

Table 1: Technical data

(1)

(1)

MOPD for media in gas form is approx. 1 bar greater.

MOPD for media in gas form is approx. 1 bar greater.

(2)

(2)

The kv value is the water ow in m3/h at a pressure drop in the valve of 1 bar, ρ = 1000 kg/m3.

The kv value is the water ow in m3/h at a pressure drop in the valve of 1 bar, ρ = 1000 kg/m3.

Table 2: Rated capacity

(3)

(3)

Rated liquid and suction vapour capacity is based on evaporating temperature te = -10 °C, liquid temperature ahead of valve tl = +25 °C, and

Rated liquid and suction vapour capacity is based on evaporating temperature te = -10 °C, liquid temperature ahead of valve tl = +25 °C, and
pressure drop across valve ∆p = 0.15 bar. Rated hot gas capacity is based on condensing temperature tc = +40 °C, pressure drop across valve ∆p

pressure drop across valve ∆p = 0.15 bar. Rated hot gas capacity is based on condensing temperature tc = +40 °C, pressure drop across valve ∆p
= 0.8 bar, hot gas temperature th = +60 °C, and subcooling of refrigerant ∆t

= 0.8 bar, hot gas temperature th = +60 °C, and subcooling of refrigerant ∆t

sub

sub

= 4 K.

= 4 K.

Table 3: Rated capacity

(4)

(4)

Rated liquid and suction vapour capacity is based on evaporating temperature te = -40 °C, liquid temperature ahead of the vale tl = - 8 °C and

Rated liquid and suction vapour capacity is based on evaporating temperature te = -40 °C, liquid temperature ahead of the vale tl = - 8 °C and
pressure drop across the valve ∆p = 0.15 bar For other condition please refer to DIR-Calc or contact your local Danfoss oce.

pressure drop across the valve ∆p = 0.15 bar For other condition please refer to DIR-Calc or contact your local Danfoss oce.

Capacity

Liquid capacity Ql kW

Table 4: R717 (NH3)

© Danfoss | Climate Solutions | 2021.03 72886419420en-000601 | 5

Type

Liquid capacity Qe kW at pressure drop across valve ∆p bar

0.1

0.2

0.3

0.4

0.5

EVRS 3

3.8

5.3

6.6

7.6

8.5

EVRS/EVRST 10

24.7

34.9

42.7

49.3

55.1

EVRS/EVRST 15

44.4

62.8

76.9

88.8

99.2

EVRS/EVRST 20

73.9

105.0

128.0

148.0

165.0

Type

Liquid capacity Qe kW at pressure drop across valve ∆p bar

0.1

0.2

0.3

0.4

0.5

EVRS 3

3.5

4.9

6.0

7.0

7.8

EVRS/EVRST 10

22.7

32.2

39.4

45.5

50.8

EVRS/EVRST 15

40.9

57.9

70.9

81.8

91.5

EVRS/EVRST 20

68.2

96.5

118.0

136.0

153.0

Type

Liquid capacity Qe kW at pressure drop across valve ∆p bar

0.1

0.2

0.3

0.4

0.5

EVRS 3

2.6

3.7

4.6

5.3

5.9

EVRS/EVRST 10

17.2

24.3

29.8

34.4

38.5

EVRS/EVRST 15

31.0

43.8

53.7

62.0

69.3

EVRS/EVRST 20

51.7

73.0

89.5

103.0

116.0

Type

Liquid capacity Qe kW at pressure drop across valve ∆p bar

0.1

0.2

0.3

0.4

0.5

EVRS 3

3.7

5.3

6.4

7.5

8.3

EVRS/EVRST 10

24.3

34.44248.6

54.3

EVRS/EVRST 15

43.7

61.8

75.6

87.5

97.7

EVRS/EVRST 20

72.9

103

126

146

163

t

v

°C

-100+10

+20

+25

+30

+40

+50

R717 (NH

3

)

0.84

0.88

0.92

0.9711.03

1.09

1.16

R22, R134a

0.76

0.81

0.88

0.9611.05

1.16

1.31

R404A

0.7

0.76

0.84

0.9411.07

1.24

1.47

R410A

0.73

0.79

0.86

0.9511.06

1.23

1.47

Type

Pressure drop

across valve ∆p

bar

Suction vapour capacity Q

e

kW at evaporating temperature te °C

-40

-30

-20

-100+10

EVRS/EVRST 10

0.1

3.4

4.5

5.9

7.3

8.9

10.6

0.15

4.0

5.4

7.0

9.0

10.9

13.0

0.2

4.5

6.1

7.9

10.0

12.6

15.0

EVRS/EVRST 15

0.1

6.1

8.1

10.7

13.2

16.0

19.1

0.15

7.2

9.7

12.5

16.1

19.6

23.4

0.2

8.0

11.0

14.2

18.0

22.6

27.0

Solenoid valve, Type EVRS 3-20 and EVRST 10-20

Table 5: R22

Table 6: R134a

Table 7: R404A

Table 8: R410A

 NOTE:

Capacities are based on liquid temperature tl = + 25 °C ahead of valve, evaporating temperature te = -10 °C, and
superheat 0 K.

Correction factors

When sizing valves, the table value must be multiplied by a correction factor depending on evaporating
temperature te.

Table 9: Correction factors

Suction vapour capacity Qe kW

Table 10: R717 (NH3)

© Danfoss | Climate Solutions | 2021.03 72886419420en-000601 | 6