Hi. I have a hot press immersion which I switch on at night time for about an hour on night rate to have hot water for the morning. It has broken down three times in the last 11 years since I bought the the house new. Anyway I'm thinking of getting a valve installed so I can use the gas instead. Recently I have seen someone getting a new zoned gas system in their apartment for heating hot water and it seems a faster way of heating water. Is gas cheaper than electric ? Sorry If this is a basic question, I thought I read somewhere that gas is more efficient? I'm not keen on handing over 2 k for the zoned version but how much would it cost to do the valve approximately ? Fed up of electric immersion failure in the morning and impossible to get an electrician where I live.