Danfoss EVT Data sheet
Data Sheet
Solenoid Valve
Type EVT
EVT high pressure range is a direct or servo
operated solenoid valve specially designed to
t into CO2 transcritical refrigeration systems.
They can be applied in following applications:
• EVT 1.2 direct operated for oil return, pressure
equalization/relief control, high pressure hot
gas bypass/dump and hot gas defrost.
• EVT 2.0 and 3.0 servo operated for high
pressure hot gas bypass/dump and hot gas
defrost application.
EVT valves and coils are sold separately.
Features
• Direct and servo operated mini piston
solenoid valve with compact construction
• Simple and fast mounting of Danfoss Clip-on
coil
• Designed for media temperature up to 150°C
• Working pressure up to 140 bar with standard
coils
• Copper solder connections for brazing
• Stainless steel connections for Swagelok
ttings
• Body material in ECO brass (lead free < 0.1%)
• Robust design ensures long lifetime
• Supplied in version normally closed (NC)
• In accordance with
◦ RoHS II
◦ REACH
◦ LVD and PED
AI383432144920en-000101
Features
EVT
EVT
Connection
Copper
Stainless steel
DN [mm]
1.2 – 3.0
1.2 – 3.0
Connection
ODF 3/8”
ODM 6mm
Max. working pressure [bar]
140
140
Function
NC
NC
Solenoid Valve, Type EVT
Portfolio overview
Table 1: Portfolio overview
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Valve housing
Cover
Armature assembly
Gasket
Armature spring
Seat plate
Coil O-ring
Solenoid Valve, Type EVT
Functions
Normally closed (NC)
Direct operated
EVT 1.2 is direct operated. This means that the valve can operate at 0bar dierential pressure.
Coil voltage disconnected (closed):
When the voltage to the coil is disconnected, the armature (3) with the seat plate (6) is pressed down against the
valve orice by the closing spring (5) and inlet pressure. The valve will be closed for as long as the coil is
disconnected.
Coil voltage connected (open):
The valve opens directly for full ow when the voltage is applied to coil, the armature (3) with seat plate is lifted
clear of the valve orice. The valve will be open for as long as there is voltage to the coil.
Figure 1: Direct operated
Servo operated
EVT 2.0 and 3.0 is servo operated piston solenoid valves. The servo piston principle results in a fast operating and
compact valve that can open against a high dierential pressure.
Coil voltage disconnected (closed):
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Valve housing
Cover
Armature assembly
Gasket
Armature spring
Seat plate
Piston assembly
Guide pin
Coil O-ring
Solenoid Valve, Type EVT
When the coil is disconnected, the armature (3) with seat plate (6) is pressed down against the pilot orice by the
armature spring (8). Via the equalization orice in the piston (5), the pressure above the piston rises to the same
value as the inlet pressure and the piston closes the main orice. The valve will be closed for as long as the coil is
disconnected.
Coil voltage connected (open):
When current is applied to the coil, the armature (3) is drawn up into the magnetic eld and opens the pilot orice.
This relieves the pressure above the piston (7), i.e. the space above the piston becomes connected to the outlet side
of the valve. The dierential pressure between inlet and outlet sides then presses the piston away from the main
orice and now the main orice opens for full ow. Therefore, a minimum dierential pressure of 2 bar is necessary
to open the valve and 0.4 bar to keep it open.
Figure 2: Servo operated
© Danfoss | Climate Solutions | 2021.08 AI383432144920en-000101 | 4
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