We have a Chromalox ebd-2 unit for heating our 2000sq foot home using in floor heating. This week the system started making a tapping sound and today I noticed a weird smell and the pipes around the unit hissing there was water on the floor below the unit. The temp gauge was reading as high a possible and it was dumping heat to parts of the house where the heat was not even on. A furnace guy came yesterday and replaced the circulator but this happened again today. Any suggestions?