i just isolated the boiler rather than draining the full system.
pulled a 2 prong pin out drain the excess water, and fitted my new prv.
then the reason the prv had gone faulty showed its ugly face - but thats another story
british jobs for british workers
February 2010
Automatic Answer
We may have found other answers which could help you.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix home heating systems.