Equilibar introduces a new Ultra Low Pressure Regulator that controls down to 0.3 in H20 (0.02 psig / 1 millibar(g)). Designed for static and very low flow applications, the patent pending LPR2 design extends the control range well below other commercially available regulators.
The LPR2 is now available with a bleed orifice option, which provides for more stability and responsiveness when lowering the setpoint pressure. The standard (very low bleed) option is still recommended for most bottled gas applications to minimize consumption.
Bleed Options:
Part # | Option: | Gas consumption (@ 5 in H20) | Typical applications |
---|---|---|---|
LPR2-NB | no bleed (standard) | <30 ml/min | Bottled gases (slow pressure reduction) |
LPR2-B | Bleed orifice | Approximately 250 ml/min | Instrument air (rapid pressure reduction; maximum stability) |
Outlet Ranges:
inH20 | psig | mbar(g) |
---|---|---|
0.3 – 7 | 0.01 – 0.25 | 0.75 – 17 |
1 – 10 | 0.04 – 0.36 | 2.5 – 25 |
1 – 28 | 0.04 to 1 | 2.5 – 70 |
Specifications:
Supply Pressure: | 5 – 30 psig [0.34 – 2.0 bar(g)] (stable, regulated) |
Ports: | 1/4″ NPT inlet/outlet |
Fluids: | Air and inert gases |
Major Materials: | Cast zinc, Polyethylene, Rubber |
Low Flow Test Results:
Sensitivity | +/- 0.01 in H20 (0.0004 psig) [0.025 mbar(g)] |
7 Day Stability | +/- 0.06 in H20 (0.002 psig) [0.13 mbar(g) |
Max Air Flow: | Approx 3 lpm (6 SCFH) at 30 psig supply pressure and 5 inH20 [12,5mbar] setpoint – see graph below |
Gas Consumption: | see bleed options above |
Relieving Sensitivity: | ~ 8 inH20 [20 mbar(g)] @ 1 SCFH [472 ml/min] at setpoint of 2 inH20 [5 mbar(g)] |

Low Flow / No Flow Applications
The LPR2 can be used as a stand-alone pressure source for applications requiring no flow or very low gas flow:
- Laboratory, research, scientific
- Pressure testing delicate membranes
Medium/High Flow Applications
Use in combination with Equilibar Precision Back Pressure Regulator
The driving force behind the development of the LPR2 is as a setpoint pressure source for the Equilibar Precision Back Pressure Regulator. These back pressure regulators can mirror the ultra low pressure from the LPR2 into much larger process streams, providing pressure control capabilities never before experienced in chemical processes.
- Vessel inert gas control
- HVAC
- Extrusion and blow molding cavity pressure control
Equilibar offers other precision solutions for the low pressure range including manual and electronic models.

Electronic Low Pressure Regulator The Equilibar QPV is available in ranges as low as 0 – 4 inH20 (0.14 psig / 10 mbar(g)) with extremely high sensitivity and resolution.
Contact Us for InformationSpecial Application Focus:
Precision Ultra Low Pressure Gas Supply System
Problem:
There are very few if any commercial regulators capable of precisely controlling gas pressure below 0.5 psig / 34 millibar(g) with varying flow rates.
Solution:
The LPR2 can be used in conjunction with an Equilibar precision back pressure regulator and a flow control valve to provide incredible precision and responsiveness. By venting any gas flow not required by the application, this system can accommodate forward or reverse gas flow at the application without loss of accuracy.
