Hydronic Valves | McMaster-Carr

	For Use With For Use With

	Inlet Pipe Size Inlet Pipe Size

	Body Material Body Material

	Maximum Pressure Maximum Pressure

	Valve Type Valve Type

Air Release

Ball

	Inlet Gender Inlet Gender

Female

Male

	Maximum Temperature Maximum Temperature

	Minimum Temperature Minimum Temperature

	Activation Activation

Pressure Driven

Manual

	Relief Port Pipe Size Relief Port Pipe Size

	Overall Height Overall Height

	Valve Function Valve Function

Pressure Relief

On/Off

	Mounting Orientation Mounting Orientation

Vertical

Horizontal

Any Position

	Relief Port Connection Type Relief Port Connection Type

Pipe

Vent

	Relief Port Location Relief Port Location

Top

Side

	DFARS (Defense Acquisition Regulations Supplement) DFARS (Defense Acquisition Regulations Supplement)

DFARS Specialty Metals
COTS-Exempt

	RoHS (Restriction of Hazardous Substances) RoHS (Restriction of Hazardous Substances)

RoHS Compliant

RoHS Compliant with
Exemptions

	Maximum Steam Pressure Maximum Steam Pressure

15psi

125psi

15 psi @ 250° F

	Voltage Voltage

24V AC

120V AC

	REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) REACH (Registration, Evaluation, Authorization and Restriction of Chemicals)

REACH Compliant

	For Copper Tube Size For Copper Tube Size

1/2

3/4

	Specifications Met Specifications Met

NSF/ANSI

	Seal Material Seal Material

45 Products

About Actuated On/Off Valves

With Female Inlet

With Female Inlet
and Female
Outlet

With Female/Male or Male Inlet

These valves are often used to remove air pockets in cooling and heating systems to maintain consistent flow and prevent water surges that can damage equipment. All have a vented relief port to exhaust discharge directly.

Valves with female/male inlets have an inlet with both male and female threads, so they can be connected to both male and female adapters and equipment ports.

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

NPT Female Inlet and Relief Vent

Inlet
Pipe Size	Location	Relief Port Location	Max. Pressure, psi	Temperature Range, °F	Overall Ht.		Each
Brass Body—Vertical Mount
1/8	Bottom	Top	75	33° to 240°	4 3/8"	000000	000000
1/4	Bottom	Top	150	33° to 240°	4 3/8"	000000	00000

NPT Female Inlet, NPT Female Outlet, and Relief Vent

Inlet		Outlet
Pipe Size	Location	Pipe Size	Location	Relief Port Location	Max. Pressure, psi	Temperature Range, °F	Overall Ht.		Each
Brass Body—Vertical Mount
1/8	Bottom	1/8	Side	Top	75	33° to 240°	4 3/8"	000000	000000

NPT Female/Male Inlet and Relief Vent

Inlet
Female Pipe Size	Male Pipe Size	Location	Relief Port Location	Max. Pressure, psi	Temperature Range, °F	Overall Ht.		Each
Brass Body—Vertical Mount
3/8	3/4	Bottom	Top	125	33° to 353°	6"	0000000	0000000
1/2	3/4	Bottom	Top	150	33° to 240°	4 3/4"	000000	00000

NPT Male Inlet and Relief Vent

Inlet
Pipe Size	Location	Relief Port Location	Max. Pressure, psi	Temperature Range, °F	Overall Ht.		Each
Brass Body—Vertical Mount
1/8	Bottom	Top	50	33° to 240°	2 5/8"	0000000	000000
1/8	Bottom	Top	50	33° to 240°	3 3/4"	0000000	00000
1/8	Bottom	Top	75	33° to 240°	4 3/8"	000000	00000
1/4	Bottom	Top	50	33° to 240°	4"	0000000	00000
1/4	Bottom	Top	150	33° to 240°	4 3/4"	000000	00000
1/2	Bottom	Top	150	33° to 240°	3 1/8"	0000000	00000
3/4	Bottom	Top	150	33° to 240°	3 1/8"	0000000	00000
1	Bottom	Top	150	33° to 240°	3 1/2"	0000000	00000

Corrosion-Resistant Air-Release Valves for Water and Coolant

Max. Pressure: 90 psi
Temperature Range: See table

These valves are made of corrosion-resistant materials for use in wet conditions and harsh environments. They eliminate air pockets to maintain consistent flow and prevent water surges that can damage equipment. All have a vented relief port to exhaust discharge directly.

Valve with a Buna-N seal is for use in heating and cooling systems.

Valve with an EPDM seal is for use in cooling systems only.

Inlet
Pipe Size	Location	Relief Port Location	Temperature Range, °F	Overall Ht.		Each
NPT Male Inlet and Relief Vent
Nylon Body—Buna-N Seal
1/8	Bottom	Top	40° to 180°	5 1/4"	00000000	000000
Nylon Body—EPDM Seal
1/8	Bottom	Top	40° to 212°	5 1/4"	00000000	00000

Remote-Discharge Air-Release Valves for Water

Max. Pressure: See table
Temperature Range: 32° to 150° F

Unlike valves that release discharge directly, these have a threaded relief port to direct discharge away from your work environment. Often used to increase pump efficiency, they eliminate air pockets in your system to maintain consistent flow and prevent water surges that can damage equipment. All have a cast iron body to absorb vibration for reduced noise and wear in your pipeline.

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

Inlet		Relief Port
Pipe Size	Location	Pipe Size	Location	Max. Pressure, psi	Overall Ht.		Each
NPT Female Inlet and Relief Port
Cast Iron Body
3/8	Bottom	3/8	Top	150	5 3/4"	00000000	0000000
1/2	Bottom	3/8	Top	150	5 3/4"	00000000	000000
1/2	Bottom	1/2	Top	300	5 1/2"	00000000	000000
3/4	Bottom	3/8	Top	150	5 3/4"	00000000	000000
3/4	Bottom	1/2	Top	300	5 1/2"	00000000	000000
1	Bottom	3/8	Top	150	5 3/4"	00000000	000000
1	Bottom	1/2	Top	150	9"	00000000	000000
1	Bottom	1/2	Top	300	5 1/2"	00000000	000000
2	Bottom	1/2	Top	150	9"	00000000	000000
2	Bottom	1/2	Top	150	10 1/2"	00000000	000000

Corrosion-Resistant Remote-Discharge Air-Release Valves for Water

For excellent corrosion resistance in wet conditions and harsh environments, these valves have no metal parts. They eliminate air pockets to maintain consistent flow and prevent water surges that can damage equipment. All have a threaded relief port that can be attached to a drain line for remote discharge.

Inlet		Relief Port
Pipe Size	Location	Pipe Size	Location	Max. Pressure, psi	Temperature Range, °F	Overall Ht.		Each
NPT Female Inlet and Relief Port
PVC Body
1/2	Bottom	1/2	Top	150	32° to 140°	3"	00000000	000000
3/4	Bottom	3/4	Top	150	32° to 140°	3 1/2"	00000000	00000
1	Bottom	1	Top	150	32° to 140°	3 7/8"	00000000	00000
1 1/4	Bottom	1 1/4	Top	150	32° to 140°	4 1/2"	00000000	00000
2	Bottom	2	Top	150	32° to 140°	5 3/4"	00000000	000000

Key-Operated Air-Release Valves for Water

Max. Pressure: 150 psi
Temperature Range: 33° to 200° F

Turn the key to manually release air from radiators, heaters, and other hot water equipment. These valves have a vented relief port that exhausts discharge directly. Body is nickel-plated brass for good corrosion resistance.

Valve
Inlet						Replacement Key
Pipe Size	Location	Relief Port Location	Overall Ht.		Each		Each
NPT Male Inlet and Relief Vent
Nickel-Plated Brass Body
1/8	Bottom	Side	1"	0000000	000000	0000000	00000

Air-Release Valves for Drinking Water

Max. Pressure: 300 psi
Temperature Range: 33° to 225° F

Eliminate air pockets in your drinking water system with these valves. They meet NSF/ANSI 61, which designates them as safe to use with drinking water. They have a vented relief port to exhaust discharge directly.

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

Inlet		Relief Port
Pipe Size	Location	Pipe Size	Location	Overall Ht.		Each
NPT Female Inlet and Relief Port
Cast Iron Body
1/2	Bottom	1/2	Top	7"	0000000	0000000
1	Bottom	1	Top	9 1/2"	0000000	000000
2	Bottom	2	Top	12"	0000000	000000
3	Bottom	3	Top	12"	0000000	00000000

Air-Release Valves for Steam

Our only air-release valves for steam, these seal shut when steam enters the valve to prevent system contents from escaping through the relief port. They are commonly used to eliminate air pockets in steam mains and risers. All exhaust discharge directly through the vented relief port.

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

	Inlet
Max. Steam Pressure, psi	Pipe Size	Location	Relief Port Location	Temperature Range, °F	Overall Ht.		Each
NPT Male Inlet and Relief Vent
Brass Body
15	3/4	Bottom	Top	212° to 249°	6"	0000000	000000
125	3/4	Bottom	Top	212° to 353°	6"	0000000	000000

Air-Release Valves for Oil and Fuel

Max. Pressure: 400 psi
Temperature Range: -20° to 500° F

Use this valve to eliminate air pockets in systems for oil, diesel fuel, gasoline, and kerosene. Valve has a vented relief port to exhaust discharge directly. Body is 304 stainless steel for excellent corrosion resistance.

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

Inlet		Relief Port
Pipe Size	Location	Pipe Size	Location	Overall Ht.		Each
NPT Female Inlet and Relief Port
304 Stainless Steel Body
3/4	Bottom	1/2	Top	7"	0000000	0000000

Motor-Driven On/Off Valves with Solder-Connect Fittings

Valve Type: Ball
For Use With: Water, Steam
Seal Material : Buna-N Rubber
Specifications Met: C-UL Listed, UL Listed

Slide copper pipe into the solder-connect fittings on these valves and weld for a strong, permanent connection. They’re often used for remote on/off control in heating and cooling systems. All operate on electricity to automatically start and stop flow. Valves do not require a minimum pressure drop between the inlet and the outlet for operation. They are normally closed unless actuated. All are standard port, so they slightly restrict flow.

The actuator is directly mounted to the valve body to minimize movement and reduce wear. The manual override allows you to operate the valve during power outages.

Flow coefficient (Cv) is the amount of water (in gallons per minute) at 60° F that will flow through a fully open valve with a difference of 1 psi between the inlet and the outlet.

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

									Overall
For Tube OD	For Copper Tube Size	Flow Coefficient (Cv)	Max. Pressure	Max. Steam Pressure	Pressure Drop	Actuation Time, sec.	Temp. Range, °F	Valve Lg.	Lg.	Ht.		Each
Brass Body with Wire Leads
24V AC
5/8"	1/2	4	300 psi @ 250° F	15 psi @ 250° F	Zero Pressure Drop	9	35° to 250°	3 1/2"	3 11/16"	4 1/4"	00000000	0000000
7/8"	3/4	4	300 psi @ 250° F	15 psi @ 250° F	Zero Pressure Drop	9	35° to 250°	3 1/2"	3 11/16"	4 1/4"	00000000	000000
1 1/8"	1	4	300 psi @ 250° F	15 psi @ 250° F	Zero Pressure Drop	9	35° to 250°	3 1/2"	3 11/16"	4 1/4"	00000000	000000
120V AC
5/8"	1/2	3	300 psi @ 250° F	15 psi @ 250° F	Zero Pressure Drop	9	35° to 250°	3 1/2"	3 11/16"	4 1/4"	00000000	000000
7/8"	3/4	3	300 psi @ 250° F	15 psi @ 250° F	Zero Pressure Drop	9	35° to 250°	3 1/2"	3 11/16"	4 1/4"	00000000	000000
1 1/8"	1	3	300 psi @ 250° F	15 psi @ 250° F	Zero Pressure Drop	9	35° to 250°	3 1/2"	3 11/16"	4 1/4"	00000000	000000