30 inHg to 30 Psi Vacuum Glycerin Liquid Filled Low Pressure Gauge, 2.5" Dial Size, 1/4" NPT Lower Mount, Stainless Steel Case, for Air Conditioning Manifolds, HVAC, Air Pump Vacuum Test

Excellent Quality. Good damping of needle variations. Easy to install. Easy to read. Just what we needed on our commercial swimming pool pump inlets. It allows us to balance the pumps perfectly.All in all this is a great functioning gauge. Well worth a full 5 stars.

Used this gauge on my outdoor lawn sprinkler pump and it worked out very well. I checked the reading using another known good gauge on my air compressor to verify that the reading was fairly accurate, and both gauges did show the same pressure.I did install it without snipping the tip off the rubber relief valve, which I learned was the proper thing to do, and one hot day with the gauge in the full sun I saw the pressure had risen to 40 psi without the pump running. Apparently this is what happens when the gauge cannot relieve the internal pressure from the heat expansion. Easily corrected by simply squeezing the rubber valve edge away from the casing for a moment.

The SENCTRL 30 inHg Vacuum Silicone Oil Liquid Filled Low Pressure Gauge is a high-quality, precision instrument designed for measuring low-pressure and vacuum applications. With its oil-filled design, this gauge offers enhanced durability and accuracy, making it suitable for automotive, industrial, and mechanical applications. Below is a detailed review of the product based on its features, performance, and value.Features & Specifications:Vacuum Measurement Range: The gauge measures a vacuum pressure range of 30 inHg, which is ideal for low-pressure and vacuum systems in automotive, industrial, and laboratory applications. This range is sufficient for most systems that require precise monitoring of negative pressure or vacuum levels.Oil-Filled Design: The gauge is silicone oil-filled, which helps dampens vibrations and provides better protection for the internal components. This design also ensures greater accuracy in reading, especially when subjected to fluctuating pressures or vibrations in engine bays or industrial environments.Dial Size & Visibility: The 2.5-inch dial size provides a clear, easy-to-read display of the pressure measurement. The large dial makes it easier to read even from a distance or under low-light conditions, which is essential in many automotive and workshop settings.Lower Mount with 1/4" NPT: The gauge features a 1/4" NPT (National Pipe Thread) lower mount, which is a common size used for industrial and automotive applications. This ensures easy installation into existing systems, whether it's used for vacuum lines, oil pressure monitoring, or other low-pressure applications.Material and Construction: The gauge is made of high-quality materials, with a durable casing that can withstand the rigors of everyday use in demanding environments. The oil-filled silicone helps to protect the internal components from moisture, dust, and other environmental factors, which extends the life of the gauge.Accuracy and Durability: The liquid-filled design not only protects the internal mechanism but also helps improve accuracy by stabilizing the needle movement, ensuring steady readings even in dynamic conditions.Pros:Enhanced Accuracy: The oil-filled design ensures steady needle movement and reliable readings, even in systems prone to vibration or fluctuating pressures. This makes it ideal for precise vacuum pressure monitoring, especially in automotive applications.Long-Lasting Durability: The silicone oil protects the internals from damage caused by shocks, vibrations, and moisture, extending the life of the gauge. The oil also helps prevent the needle from sticking or jumping, providing more consistent readings over time.Clear and Easy-to-Read Dial: The 2.5-inch dial makes it easy to monitor pressure readings from a distance, which is useful for installations in tight spaces or hard-to-reach locations.Wide Range of Applications: The gauge’s 30 inHg vacuum range and 1/4" NPT lower mount make it suitable for a variety of low-pressure and vacuum applications, such as measuring vacuum pressure in engines, fuel systems, or even HVAC and laboratory environments.Protection from Environmental Factors: The oil-filled feature provides protection against moisture and dust, which is critical for maintaining accuracy and functionality in harsh environments like engine bays or industrial settings.Affordably Priced: Compared to other high-quality vacuum gauges on the market, the SENCTRL 30 inHg Vacuum Silicone Oil Liquid Filled Low Pressure Gauge offers excellent value for money, making it an affordable option for those who need reliable performance without breaking the bank.Cons:Size May Be Too Large for Some Installations: The 2.5-inch dial size might be too large for installations in very tight spaces, especially in automotive or machinery setups with limited room. Users with constrained installation areas may want to look for smaller, more compact options.Potential for Oil Leaks: While the oil-filled design offers many benefits, there is a risk of the oil leaking over time if the gauge is damaged or improperly installed. However, this is generally rare with quality gauges and can be mitigated with careful handling and proper installation.Not Ideal for High-Pressure Applications: This gauge is specifically designed for low-pressure and vacuum measurements. It would not be suitable for applications that require high-pressure readings, so users with high-pressure systems may need a different gauge.Conclusion:The SENCTRL 30 inHg Vacuum Silicone Oil Liquid Filled Low Pressure Gauge is an excellent choice for anyone looking for a reliable, accurate, and durable vacuum gauge for low-pressure systems. Its oil-filled design ensures stability and protection against vibrations, moisture, and shocks, which makes it well-suited for automotive, industrial, and other high-demand applications.The 2.5-inch dial offers easy-to-read pressure readings, and the 1/4" NPT lower mount ensures straightforward installation in most systems. With a vacuum pressure range of 30 inHg, it’s perfect for monitoring fuel systems, engine vacuum lines, HVAC systems, and more.While the gauge may be a bit large for some tight installations, its overall performance, accuracy, and durability make it a great value for the price. If you need a high-quality vacuum gauge for a low-pressure system or vacuum application, the SENCTRL 30 inHg is a solid and affordable choice.

High quality , easy to read face, time will tell the longevity of this gauge.

Great product, and inexpensive definitely recommend it

I used this on a reciprocating pump outlet. The glycerin dampens the oscillations very well, and will make this last much longer. Conventional gauges will get destroyed by these pressure fluctuations in no time.

This glycerin filled gauge seems to be excellent quality and very accurate. I have purchased three additional gauges (same brand and size with varying pressures and mounting configurations) since the purchase of this one as a testament to my satisfaction with this one. The 2.5-inch size is clear and easy to read.

Works great on pool filter and sturdier than original.