Hello, my sisters boiler was installed about 3 years ago along with CH system but last week wouldnt start showing an LF fault after searching around on the different forums and here i figured it must have been a blocked condensate pipe or s trap after removing the strap and a bucket of water from the condenser and cleaning out the strap (full of aluminium oxide crystals) putting it all back together the boiler fired up fine and stayed running for a full week.
seven days later she now has a different problem
she woke up to cold house and a flashing LE on the boiler i told her to switch it off and went round, turned it on and boiler when through the startup as normal and then fired up for ch it worked fine for about an hour or so and then shut off flashing the LE again, I reset the boiler i get number 5 and then a c and then straight away flashing le if i turn the boiler off and then on the pump comes on fan comes on but then i get 5 and then c a click and then a flashing le
but if i leave it off for 20 minutes or so it will start up as normal and run for anything from 20 minutes to an hour and a half until interrupted ie the central heating is up to temeperature or the hot water is used and then the next time it tries to fire up for ch it returns the same fault.
If i reset it same problem occurs, if i switch it on/off at boiler same problem but if i switch it on/off at the mains for a few minutes it will fire up again.
so far i have surmised that it probably is a fault within the electronics of the pcb and not something to do with heat as i first thought, but the LE fault does seem to be triggered during some test check prior to the central heating coming on because if i turn the boiler on and run the hot water straight away it works fine and the fault is not triggered until it shuts off dhw and tries to fire for central heating
so is there anything i can check for? has anyone had a similar problem? i suspected overheat thermostat and control thermistors how do i check these? does anyone know what this boiler checks/monitors prior to firing up for central heating? it might be worth adding that when i tested the voltage on the wires going to the thermistors that they seemed to be fluctuating from between 0.7 to 1.4 volts without being connected to the thermistors is this normal?
any help would be greatly appreciated thanks
seven days later she now has a different problem
she woke up to cold house and a flashing LE on the boiler i told her to switch it off and went round, turned it on and boiler when through the startup as normal and then fired up for ch it worked fine for about an hour or so and then shut off flashing the LE again, I reset the boiler i get number 5 and then a c and then straight away flashing le if i turn the boiler off and then on the pump comes on fan comes on but then i get 5 and then c a click and then a flashing le
but if i leave it off for 20 minutes or so it will start up as normal and run for anything from 20 minutes to an hour and a half until interrupted ie the central heating is up to temeperature or the hot water is used and then the next time it tries to fire up for ch it returns the same fault.
If i reset it same problem occurs, if i switch it on/off at boiler same problem but if i switch it on/off at the mains for a few minutes it will fire up again.
so far i have surmised that it probably is a fault within the electronics of the pcb and not something to do with heat as i first thought, but the LE fault does seem to be triggered during some test check prior to the central heating coming on because if i turn the boiler on and run the hot water straight away it works fine and the fault is not triggered until it shuts off dhw and tries to fire for central heating
so is there anything i can check for? has anyone had a similar problem? i suspected overheat thermostat and control thermistors how do i check these? does anyone know what this boiler checks/monitors prior to firing up for central heating? it might be worth adding that when i tested the voltage on the wires going to the thermistors that they seemed to be fluctuating from between 0.7 to 1.4 volts without being connected to the thermistors is this normal?
any help would be greatly appreciated thanks
