Hi Colin, you're probably better of just fitting an immersion heater element straight into your tank. There's some good threads about it on here. That's how I came to fit mine. It cost me under £100 for all the bits but it has been worth it. I just plug it in for a few hours on a timer in the early hours, then I'm set for the day. Use it when I feel like it. Cheaper than the lpg set up but they can heat water instantly and much hotter than an immersion set-up.