potterton performa 30 HE?
Hi water working fine but when central heating is turned on upstairs radiators work ok but downstairs nothing. Temperature on the boiler goes up to max very quickly and flow pipe is red hot, pump and trv's have been replaced and diverter valve checked. No fault lights showing . drain water downstairs and rad gets warm but cools as soon as draincock is closed Any help please
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Tom, December 2013
