Isar HE24 Problems :(

[wakar]

I have a Ideal Isar HE24 boiler that was installed under the warm front scheme and is just about 6.5 years old.

It has been showing an L:9 fault for the last 2 weeks. When it first started I could press the rest button and it would clear it and the boiler would run fine with DHW and CH working fine. However over the last week the L9 is more prominant and does not clear with the reset button.

I have increased the pressure to between 1 and 2 bars and bled the radiators, and reset.

If i leave the boiler off for a while and then switch it on, it tries firing up and the pressure goes to 2bars, but then dies out and I get the L9 error. If I reset it, it then also shows 0:E or 0:3 (cannot tell which one it is, either the digital 3 or capital E, as it has the vertial lines missing ) and then returns to the L9 error after a few minutes.

The Diverter valve, and heat exchange plate both have been replaced and this has not resolved it. Could it be the pump??

Please help as i have 3 small kids and not hot water/heating

Many Thanks in advance
Wakar

 

[swbjackson]

L9 and also 3 horizontal bars are an overheat error. Could also be a faulty thermistor.

 

[shambolic]

It's probably pump but you could have cooked the heat exchanger by continually pressing reset button.
As every time you reset the boiler will come on and try to get to full temperature before cut off which can cause excessive build up in hex leading to AAV melting and end panel on hex leaking.

 

[wakar]

It's probably pump but you could have cooked the heat exchanger by continually pressing reset button.
As every time you reset the boiler will come on and try to get to full temperature before cut off which can cause excessive build up in hex leading to AAV melting and end panel on hex leaking.

New heat exchanger was installed last night so that should be ok, as not reset since last night.. New pump to be ordered today