thermostat for Potterton Diplomat 55/68?
The thermostat on my Potterton Diplomat 55/68 is not functioning correctly in that the water is either very hot or not warm enough. The original Ranco NCA 314133 is no longer available. A,Is there an alternative that can be used? or B,is it possible to repair the existing unit? and C, are second hand units available?. Any information gratefullu received .
John andrew
May 2009