Vaporless VMI-3300 3″ In-Line Check Valve

To prevent line leak detection (LLD) false alarm nuisance problems, the LLD requires a functioning check valve upstream of itself. Without adequate pressure upstream of the LLD, the unit will reset into the slow flow position every time the pump turns off. This does not mean that the LLD must have a functioning check valve in the STP head. Pressure must simply be maintained upstream of the LLD.

A failing check valve in a 3hp or 5hp STP requires a two-man crew and a crane to pull the STP in order to access the check valve, a very costly repair. The VMI-3300 3” In-Line Check Valve is a great retrofit solution to reduce service costs. The VMI-3300 installs in the STP discharge, the LD-3000 High Capacity Line Leak Detector installs in the outlet of the VMI-3300. Installed in this manner, the VMI-3300 maintains pressure upstream of the LLD. This economical solution means there is no need to replace a failed STP check valve.