The best cure is prevention .. the practices of burying service pipes min 750mm deep and keeping pipes away from eaves and outside walls generally appears to have been forgotten due to the relatively mild winters in recent decades .. now there are all sorts of problems cropping up as a result. With most house having loft insulation there is not as much heat transfer into the roofspace thus the temp will more easily get below freezing despite the heating being on. Better to put the insulation above the pipes/tanks if possible.
Anyway remedies would depend on the circumstances .. if a service pipe then not much you can do to thaw it.. just have to wait and make sure there is no leak when it does thaw .. check the meter regularly. If in the loft then I usually turn the water off drain what can be drained and get a heater up there and make a "tent" with a tarp or blankets nailed to the rafters around the area where the pipes/tanks are and just try to keep the temp above freezing. once its thawed turn the water on slowy and check for leaks .. Resist the temptation to use your blowlamp unless you take fire precautions .. extinguisher or fire blanket to hand.
I would be interested to know also how many condensing boilers have failed due to freezing conditions I have had a few locally but I believe it may be a big problem nationally .. all comments welcome!!
Happy New Year To all!!
