I have a Worcester 26CDi EXTRA boiler,installed six years ago.
The condensate drain from the secondary heat exchanger appears to be obstructed causing a shutdown, presumably from "air pressure fault".
Having disconnected the plastic drain tube from the syphon and extended it I find that blowing back (by mouth) up the tube I encounter some resistance and can hear bubbling in the stainless steel box.
Allowing the tube to drain freely (with the boiler shut down) it discharges about two drops a second until it is empty - a couple of hours and about half a litre. Theboiler can then be started up and operates normally.
I have tried washing through with plain water from the monitoring port on the flue - with little success. Could someone please tell me:-
a) What is the chemical nature of the sludge in the stainless box?
b) What chemical flush is likely to loosen or dissolve it? (Presumably not an acid descaler as the condensate is already acid).
Thanks in anticipation. Egdiy.
The condensate drain from the secondary heat exchanger appears to be obstructed causing a shutdown, presumably from "air pressure fault".
Having disconnected the plastic drain tube from the syphon and extended it I find that blowing back (by mouth) up the tube I encounter some resistance and can hear bubbling in the stainless steel box.
Allowing the tube to drain freely (with the boiler shut down) it discharges about two drops a second until it is empty - a couple of hours and about half a litre. Theboiler can then be started up and operates normally.
I have tried washing through with plain water from the monitoring port on the flue - with little success. Could someone please tell me:-
a) What is the chemical nature of the sludge in the stainless box?
b) What chemical flush is likely to loosen or dissolve it? (Presumably not an acid descaler as the condensate is already acid).
Thanks in anticipation. Egdiy.