Could someone please advise possible cause of dirty, black water in F&E tank. This tank is also overflowing with a small drip coming out of the overflow pipe. I recently replaced the hot water cylinder (thought the coil inside the cylinder was leaking) and installed new upstairs radiators also. Flushed the completed system through also. (Downstairs radiators are old) The CH system is oil fired, gravity fed and is approx 30 yrs old. The boiler was exchanged about 15 yrs ago. The bathroom shower comes off mixer tap fed by mains cold and hot water from cylinder. Just fitted a one-way valve to the hot feed to the mixer tap just in case of back flow. I cant detect any water entering the F&E tank via the vent pipes. Also isolated the cold water feed by tying up the ballcock - I assume it's entering back up through the feed pipe? I guess the coil in the new cylinder could be leaking but being new I have my doubts.
Any suggestions would be appreciated......?
Any suggestions would be appreciated......?