Might be worthwhile trrying house insurers. Central heating system is part of 'buildings' so you would need Accidental Damage cover on buildings for this to be covered as a matter of course. If no joy there you would have to pursue the power company. I any event you need them to explain what happened and why - even your own insurers would need an explanation. Also talk to your neighbours - have they had the same problem? You're more likely to be sucessful if you get together.