Non-Return Valves

The valve block contains 3 non-return valves. Non-Return Valve No. 1 (NRV1) retains compressor air pressure by preventing flow back to compressor. Non-Return Valve No. 2 (NRV2) prevents loss of pressure in system if reservoir pressure drops. It also ensures correct flow through inlet valve. Non-Return Valve No. 3 (NRV3) ensures correct flow through exhaust valve.