ideal isar L9 problem. surprise, surprise! :(

[baldy874]

hi. i wonder if anyone can shed any light.

i have an ideal isar he30. error code, L9. on reset it went onto 3 horizontal bars which according to the book, they do this until the heat exchanger drops below 50.

i've read a load of posts here, and so far i have drained the boiler down, removed the condense trap and cleaned. all fine. removed plate exchanger and washed through, but that was all clear too.

not sure if my multimeter is pants because i can get any readings from the dry fire thermistor or the control thermistor.

fired it back up and it went straight onto L9 again and fan went beserk and all got rather hot, rather quickly,

any ideas please? got the wife whining she's cold already!

 

[diamondgas]

Put some water in the system!!!

Re-pressurise to at least 1 bar.... You GSR?

 

[baldy874]

pressurised to just over 1 bar.

not GSR. fairly competent and know my limits.

 

[diamondgas]

Then next sage is check the pump is working and the boiler is filled with water ... AAV open etc!

🙂

 

[baldy874]

pump appears to be running ok. AAV not touched. all went cold when i filled it back up and pressure went down to half a bar when i opened isolators, so assume all full with water.

 

[diamondgas]

re-pressurised to 1 bar for sure ... if the aav is open then 't' will run untill hot water pre-heat is satisfied then the boiler will change to 'c' and circulate through heating ... what stage does the boiler shut off to L-9?

 

[baldy874]

just drained down and refilled again.

fired it up, went onto "d", burner light came on, heated up very quickly then went onto L9 in about 20 seconds.

 

[baldy874]

oh. on fire up display went "0" - "5" first before "d" and burner light.

 

[diamondgas]

Definitely sounds like the heat exchanger is dry ... 'd' is hot water demand .. same a 't' as far as the diverter is related ... I'd be checking the aav to make sure its open .. a nightmare of a position to be honest!!!

If you're sure the pump is running then then it sounds like water is not! Could be pump impeller has dislodged? Unusual!!!!

 

[stevetheplumber]

should show three vertical bars to represent the prison cell the designers of these boiler should be in

 

[Billy Bob Bob]

sounds like a pump,air,circulation issue getting hot water?

 

[baldy874]

wierd.

got some air out of the AAV but still goes to "d" and fires the burner on start up? hot taps all bled btw.

 

[baldy874]

and yes, the designers of this trash should be locked up! i've read about a LOT of problems with them.

 

[diamondgas]

Alas until you get the water to heat up the integral plate hex you are at a loss ... Unless you can remove the actuator and mess with the diverter?

 

[baldy874]

aye. will whip that out next. just had pump out and quicklt flicked power on for a couple of seconds. pump 100% working.

cant understand why as soon as i turn it on, it's calling for hot water and firing up?

 

[SimonJohns]

aye. will whip that out next. just had pump out and quicklt flicked power on for a couple of seconds. pump 100% working.

cant understand why as soon as i turn it on, it's calling for hot water and firing up?

They have a built in preheat. If Hws thermister says cold it will heat that first

 

[baldy874]

They have a built in preheat. If Hws thermister says cold it will heat that first

i see. so if the thermistor is toast it will think it's calling for DHW?

 

[SimonJohns]

No of that's toast it just won't work

 

[baldy874]

would a toasted thermistor cause it to demand hot water first on fire up pre heat?

if i recall, it normally goes to "t" then stright to "0" and ready for action.

 

[SimonJohns]

It's 12:20. Call a GSR in the morning.