Fault on ferroli falcon 2

Hello, I have a ferroli falcon 2 boiler (yes it is pretty old). A few days ago the hot water started going hot and cold when running.

Monitoring the boiler, the demand light works fine. When the water gets up to temperature every 10 seconds or so, the boiler stops for a fraction of a second then immediately restarts (which obviously takes a few seconds to start up again). This causes the water temperature to fluctuate. The demand light is on continually.

I've tried replacing the temp sensor on the dhw and the flow sensor. I also tried replacing the PCB. All resulted in exactly the same behaviour.

The heating works fine, with no cutouts the boiler runs perfectly so it is only the hot water that has a problem.

Any suggestions as to what the fault is?

Thanks

Taf

Time for a gas safe engineer sorry

ShaunCorbs said:

Time for a gas safe engineer sorry

Click to expand...

What would they do that I haven't done already?

Sorry, I'm a bit negative when it comes to calling out "gas safe" engineers. Unless you can recommend a good one in Gloucestershire?

Previous experiences (from gas safe engineers) include (but not limited to)...

Leaving live mains wires sticking out the bottom of the boiler
"Unable to get the manual for the boiler"
Inability to follow the diagnosis flow chart
Attempting to charge me 500 pound to replace a PCB which I said I could get for 80. They said, fine, give me 200 and the PCB and I will change it for you. Fault turned out to be the igniter in the chamber which was a free fix.
After repair, boiler made a terrible noise - was informed that "These boilers always sound like that". After they left, I took the cover off to find that the vent fan was hitting one of the rubber hoses. I just moved the hose and it was fine.
Boiler leaking after "repair".
Telling me about their family drug problems

Incidentally, some of the cases above were from a well known national company that will remain nameless.

Again - I realise not everyone is like that, it is just my personal experience. Happy to get recommendations...

I would suggest you contact gas safe to report shoddy work

We can’t advise as your not qualified sorry