Can I have both instantaneous & gas storage cylinder installed? Comments Off on Can I have both instantaneous & gas storage cylinder installed? 18 Jan 2016 Vote Up 0 Vote Down Answered Public Public Private Installations Anonymous asked January 18, 2016 Hi There, Can I have both instantaneous & gas storage cylinder installed? 1 answer Vote Up 0 Vote Down Public ⋅ January 19, 2016 Yes but there are much better ways to design your heating and hot water systems that utilise the gas and storage cylinder. #1 Please login or Register to Submit Answer