Follow along to find information on the F340e and F680e check valve.
 

The check valve improves pump performance by preventing back flow and reducing pressure fluctuations/spikes. This reduces surging at the applicator.
 

The check valve should be used with highly compressible gypsum based materials. With high density, Portland cement based materials the check valve can be removed. The back flow caused by highly compressible gypsum based materials is experienced much less with high density materials. With high density materials, the restriction of the check valve can reduce pump performance more than the check valve can improve performance. The check valve can be replaced with a 1.5" NPT nipple fitting.