Bürkert 455625 Type 0290 is a servo-assisted 2/2-way diaphragm valve designed for reliable fluid control. The valve opens without differential pressure, facilitated by the fix-coupling of the diaphragm to the magnetic core. An integrated 'soft-kick' function ensures gentle opening. The 455625 variant features a 1 1/2" NPT brass body, FKM seals, and operates at 24V AC/DC. Kick and drop electronics are moulded into the epoxy solenoid coil for reduced electrical power consumption.

General Technical Data

Feature	Specification
Orifice	DN 12...DN 50 (Standard variant)
Circuit function	A (Normally closed)
Body material	Brass, stainless steel 1.4581
Seal material	NBR, FKM, EPDM
Coil material	Epoxy (Thermal insulation class H)
Duty cycle	100% continuous operation
Voltage tolerance	±10%
Degree of protection	IP65 with cable plug
Installation position	As required, preferably with actuator upright

Operating Conditions

The 455625 variant with FKM seals is suitable for per solutions and hot oils with additives, with a permissible medium temperature of 0 °C to +90 °C (with high-performance electronics). Maximum ambient temperature is +55 °C (up to +70 °C depending on switching cycles).

Approvals and Conformities

Depending on the specific configuration, the Type 0290 series supports various approvals:

• North America: UL Listed / UL Recognized (UL 429), CSA (CAN/CSA-C22.2 No. 139-19).
• Drinking Water: Materials comply with UBA assessment principles; WRAS/WRC approval available for specific seal materials.
• Fuel Gases: Complies with Regulation (EU) 2016/426 and DVGW DIN EN 161 (variable code PO17).

Material Specifications

No.	Element	Material
1	Coil	Epoxy
2	Stopper	Stainless steel 1.4105, 1.4113 or 1.4523
3	Shading ring (AC only)	Brass variant: copper; Stainless steel variant: silver
4	Spring	Stainless steel 1.4310
5	Magnetic core	Stainless steel 1.4105 or 1.4113
6	Core guide tube	Stainless steel 1.4303
7-9	O-ring	NBR, FKM, EPDM
10	Diaphragm plate	Brass variant: CuZn37; Stainless steel variant: 1.4401
11	Diaphragm	NBR, FKM, EPDM
12	Body	Brass or stainless steel 1.4581
13	Pilot valve seat	Brass variant: MS; Stainless steel variant: 1.4401
14	Seat seal	NBR, FKM, EPDM

Dimensions

Threaded Variant

Note: Dimensions in mm. The dimensions D1 and F1 apply to G thread. The dimensions D2 and F2 apply to NPT thread.

DN	A	B	G (D1)	G (F1)	NPT (D2)	NPT (F2)	E	L	SW	J	H
12	80	94	G 1/2	14	NPT 1/2	13.7	40	74.5	27	81	40
20	106	122	G 3/4	16	NPT 3/4	14	60	100	32	93	49
25	110.5	131	G 1	18	NPT 1	16.8	70	115	41	98	49
32	120	145	G 1 1/4	20	NPT 1 1/4	17.3	85	126	50	106	49
40	124	154	G 1 1/2	22	NPT 1 1/2	17.3	85	126	60	106	49
50	176	211	G 2	24	NPT 2	17.6	115	164	70	133	72

Flange Variant (DIN EN 1092-1)

DN	A	B	C	E	∅ G	L	M	K	J	H
25	110.5	170.5	68	70	120	160	14	85	98	49
32	120	190	78	85	140	180	18	100	106	49
40	126	201	88	85	150	200	18	110	106	49
50	176	258.5	102	115	165	230	18	125	133	72

Installation and Safety

Safety Instructions

• High Pressure: Before loosening lines or valves, switch off the pressure and vent the lines.
• Electrical Voltage: Before accessing the device or the system, switch off the power supply and secure it to prevent reactivation.
• Hot Surface: Keep the device away from highly flammable substances and do not touch with bare hands during continuous operation.

Installation Recommendations

For safe operation of the solenoid valve, a dirt trap (≤400µm) must be installed before the valve inlet. For devices with approval according to the European Gas Appliances Directive, installation of the filter is mandatory.