FER Falcon problem

[Negsy]

Problem with an FER Falcon boiler, in CH mode. HW all ok.

The boiler starts up ok initially but after it goes into CH standby it will not re-ignite (it doesn't even seem to try). afetr a few minutes it locks out.

I would be gratefull for any help.

 

[Agile]

If it goes into an ignition lockout then it may well need a gas registered engineer to investigate.

It might well be a PCB fault though.

I suppose you could measure the sensor resistances first.

Tony

 

[Negsy]

If it goes into an ignition lockout then it may well need a gas registered engineer to investigate.

It might well be a PCB fault though.

I suppose you could measure the sensor resistances first.

Tony

Thanks Tony,

Which sensor should I check?

I am ok with the electrics but if it comes down to the gas side I will get somebody in. I have a wiring diagram, but would prefer a schematic showing the internal detail, but failing this any information would be appreciated.

N.

 

[Agile]

There are two temperature sensors, one on the DHW pipe and one on the CH flow pipe.

You should turn the boiler of for a couple of hours and the sensors should be the same and probably aboiut 10k at room temperature.

But its likely to be something combustion related.

As always you will need a competent boiler engineer not a gas qualified plumber who will just want to fit a new boiler.

Tony

 

[ollski]

Problem with an FER Falcon boiler, in CH mode. HW all ok.

The boiler starts up ok initially but after it goes into CH standby it will not re-ignite (it doesn't even seem to try). afetr a few minutes it locks out.

I would be gratefull for any help.

It won't try for about 3 minutes after the last heating or hw demand which probably accounts for that part of the problem.

 

[Agile]

Thats right but they dont usually just go into lockout after teh CH delay period.

I have encountered PCB faults where they just stay on the delay without coming back to CH ( unless the DHW is used ).

Probably an electrolytic on the PCB dried out.

Tony

 

[Negsy]

Problem with an FER Falcon boiler, in CH mode. HW all ok.

The boiler starts up ok initially but after it goes into CH standby it will not re-ignite (it doesn't even seem to try). afetr a few minutes it locks out.

I would be gratefull for any help.

It won't try for about 3 minutes after the last heating or hw demand which probably accounts for that part of the problem.

Yes that fits. After about 3 mins the red light (CH standy) goes out and the CH green light comes on. about another minute or so and the lock out light comes on.

N.

 

[bengasman]

You sometimes get funny faults on these from the sensor connectors. Not sure if they come loose or get a bit dirty or corroded.
You can try undoing and redoing them a couple of times.

 

[Negsy]

Thats right but they dont usually just go into lockout after teh CH delay period.

I have encountered PCB faults where they just stay on the delay without coming back to CH ( unless the DHW is used ).

Probably an electrolytic on the PCB dried out.

Tony

This sounds like it could be the problem.

I think, but will check, that CH works ok if HW is running. There were times where things worked fine but i didn.t work this through.

Needs a few more clarification checks = will go through tomorrow

 

[Negsy]

Problem solved (I think).

I took all the plug leads off the two circuit boards and replacedc them just in case of high resistance connections.


I then checked the two sensors - HW= 9.5k CH = 6.6k, so possible future problem here - BUT the lead was disconnected from the CH sensor very poor connector THIS seems to be the problem, may happen again so I will sort out a better connection.


Thanks for all the help.