yes they can do it, and even if you do pay the full amount it can take nearly 2 weeks for them to turn it back on. i owe them around the same amount but when you get that final letter you really should be sorting it out with their credit department. they are usually ok with a minium payment agreement. i dont think you have a way of getting out of paying to get it back on. But maybe enquire about a prepay meter system for the future. I dont know how anybody is supposed to pay for heating bills in this country the price is ridiculous, it was costing us nearly 80e a week for gas during the cold months, here's hoping for a long hot summer. Good Luck.