Can we replace open cap with lever PSV with closed cap with no manual lever PSV?

Yes, you can replace an open cap lever pressure safety valve (PSV) with a closed cap PSV that does not have a manual lever. However, it's essential to ensure that the new PSV meets the same pressure and flow specifications as the original and complies with relevant safety standards. Additionally, consider the implications of not having a manual lever for testing and maintenance, as it may affect operational safety and compliance. Always consult with a qualified engineer before making such changes.