Steam Pressure Switches | McMaster-Carr

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24 Products

About Pressure-Relief Valves

Valve With Test Lever

Valve With Swivel Test Lever

For Use With: Steam
Temperature Range: -60° to 400° F

These valves meet ASME Code Section I for use with steam power boilers requiring pressure relief above 15 psi. They spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. For remote discharge, attach a drain line to the threaded relief port. Valves have a durable bronze body for a long service life.

EPR rubber seals provide better leak protection than brass seals.

Swivel test levers rotate 360° around the valve for use in areas with limited clearance.

For technical drawings and 3-D models, click on a part number.

Inlet			Relief Port
Pipe Size	Location	Maximum Pressure, psi	Pipe Size	Location	Overall Ht.	Test Mechanism	Test Lever Type	Valve Type	Specifications Met	Choose a Set Pressure, psi		Each
NPT Male Inlet and NPT Female Relief Port
Bronze Body—Brass Seal
1/2	Bottom	250	3/4	Side	6 1/2"	Lever	__	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	0000000
1/2	Bottom	250	3/4	Side	7 5/16"	Lever	Swivel	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
3/4	Bottom	250	1	Side	7 1/2"	Lever	__	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
3/4	Bottom	250	3/4	Side	7 5/16"	Lever	Swivel	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
1	Bottom	250	1	Side	7 5/8"	Lever	Swivel	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
1	Bottom	250	1 1/4	Side	8 1/2"	Lever	__	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
1 1/4	Bottom	250	1 1/2	Side	9 5/8"	Lever	__	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
1 1/2	Bottom	250	1 1/2	Side	9 5/8"	Lever	Swivel	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
1 1/2	Bottom	250	2	Side	10 5/8"	Lever	__	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
2	Bottom	250	2 1/2	Side	13 5/8"	Lever	__	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
Bronze Body—EPR Seal
1/2	Bottom	250	3/4	Side	6 1/2"	Lever	__	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
3/4	Bottom	250	1	Side	7 1/2"	Lever	__	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000
1	Bottom	250	1 1/4	Side	8 1/2"	Lever	__	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	0000000	000000

ASME-Code Fast-Acting Pressure-Relief Valves for Low-Pressure Steam

For Use With: Steam
Specifications Met: ASME BPVC.IV
Max. Temperature: 250° F

For use with low-pressure steam-heating boilers requiring pressure relief at 15 psi, these valves meet ASME Code Section IV. All spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. Body is bronze for durability and a long service life.

Vented relief ports exhaust discharge directly.

Threaded relief ports can be attached to a drain line for remote discharge.

For technical drawings and 3-D models, click on a part number.

Straight

Inlet				Relief Port
Pipe Size	Connection	Location	Maximum Pressure, psi	Connection Type	Location	Steam Flow Capacity, lbs./hr.	Set Pressure, psi	Overall Ht.	Test Mechanism	Valve Type		Each
Bronze Body—EPDM Seal
3/4	NPT Male	Bottom	15	Vent	Top	410	15	2 7/8"	Lever	Pop Safety	0000000	000000

Elbow

Inlet				Relief Port
Pipe Size	Connection	Location	Maximum Pressure, psi	Pipe Size	Connection	Location	Steam Flow Capacity, lbs./hr.	Set Pressure, psi	Overall Ht.	Test Mechanism	Valve Type		Each
Bronze Body—PTFE-Coated EPDM Seal
3/4	NPT Male	Bottom	15	3/4	NPT Female	Side	470	15	3 13/16"	Lever	Pop Safety	0000000	000000
1	NPT Male	Bottom	15	1	NPT Female	Side	640	15	4"	Lever	Pop Safety	0000000	000000
1 1/4	NPT Male	Bottom	15	1 1/2	NPT Female	Side	1,200	15	4 1/2"	Lever	Pop Safety	0000000	000000
1 1/2	NPT Male	Bottom	15	2	NPT Female	Side	1,900	15	5 1/4"	Lever	Pop Safety	0000000	000000
2	NPT Male	Bottom	15	2	NPT Female	Side	2,500	15	6 9/16"	Lever	Pop Safety	000000	000000
2 1/2	NPT Male	Bottom	15	2 1/2	NPT Female	Side	3,520	15	8 1/8"	Lever	Pop Safety	000000	000000
3	NPT Male	Bottom	15	3	NPT Female	Side	4,100	15	9 1/16"	Lever	Pop Safety	000000	000000

Fast-Acting Pressure-Relief Valves for Ultra-Low-Pressure Steam

For Use With: Steam
Max. Temperature: 250° F

Choose these valves for small steam-heating boilers requiring pressure relief between 5 psi and 12 psi. They spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. All have a bronze body for durability and a long service life.

Vented relief ports exhaust discharge directly.

Threaded relief ports can be attached to a drain line for remote discharge.

For technical drawings and 3-D models, click on a part number.

Straight

Inlet			Relief Port
Pipe Size	Connection	Location	Connection Type	Location	Overall Ht.	Test Mechanism	Valve Type	Choose a Set Pressure, psi		Each
Bronze Body—EPDM Seal
3/4	NPT Male	Bottom	Vent	Top	2 7/8"	Lever	Pop Safety	5, 6, 8, 10, 12	0000000	000000

Elbow

Inlet			Relief Port
Pipe Size	Connection	Location	Pipe Size	Connection	Location	Overall Ht.	Test Mechanism	Valve Type	Choose a Set Pressure, psi		Each
Bronze Body—EPDM Seal
3/4	NPT Male	Bottom	3/4	NPT Female	Side	3 13/16"	Lever	Pop Safety	5, 6, 8, 10, 12	0000000	000000
1	NPT Male	Bottom	1	NPT Female	Side	4"	Lever	Pop Safety	5, 6, 8, 10, 12	0000000	000000

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About Pressure-Relief Valves

ASME-Code Fast-Acting Pressure-Relief Valves for Steam

ASME-Code Fast-Acting Pressure-Relief Valves for Low-Pressure Steam

Fast-Acting Pressure-Relief Valves for Ultra-Low-Pressure Steam