Description
A non return valve is a simple but important part of an air suspension compressor system. It is a one-way pneumatic valve designed to allow air to flow from the compressor into the air tank, while preventing stored tank pressure from feeding back towards the compressor head.
In American terminology this part is usually called a check valve. In the UK it is often called a non return valve. Both names refer to the same basic component.
When the valve is working correctly, the compressor does not have to restart against full tank pressure. This helps reduce compressor strain, reduces the chance of high-amperage starts, and can help extend the service life of the compressor.
This replacement valve is particularly useful where a VIAIR compressor has been left unused for a long period, as the original valve can sometimes begin to stick. A sticking or leaking non return valve can cause slow tank pressure loss, compressor restart issues, or unnecessary strain on the motor.
This is the 1/4 inch NPT version we commonly use and supply for VIAIR 444C style installations.
Confirmed / typical applications include:
VIAIR 380C compressors using a 1/4 inch NPT inline check valve
VIAIR 400C compressors using a stainless braided leader hose with inline check valve
VIAIR 444C compressors using a stainless braided leader hose with inline check valve
VIAIR 450C compressors using a 1/4 inch NPT leader hose with inline check valve
Other compatible compressors and air systems using a 1/4 inch NPT one-way valve in the compressor leader hose or outlet port
Please note that some VIAIR compressors and other air compressors use a larger 3/8 inch leader hose/check valve arrangement. This part is not the direct replacement for those versions. Also please note the direction of flow as shown in the picture – this NRV flows from the male thread to the female one. The reverse flow is also available. If in doubt, check the thread size on your existing leader hose and valve before ordering.
Specification:
Material: Nickel plated stainless steel
Thread: 1/4 inch Male NPT to 1/4 inch Female NPT
Maximum working pressure: 450 psi
Minimum start pressure: 1-3 psi
Operating temperature: -30°C to 100°C
Suitable for air suspension and other pneumatic air systems
Installation notes:
Use a suitable pneumatic thread sealant on the threads during installation. Do not rely on PTFE tape where it may break away and enter the air system. NPT threads seal by taper, so they should be tightened carefully and not overtightened.
