Ferroli hot water problem

Friend of mine rents a house from a dodgy landlord..... he just went bankrupt, she's having problems with her ferroli boiler and his answer was "tough"
anyway.....

the problem is the hot water, it's a combi boiler, the central heating works ok, but when she turns the hot tap on, the boiler fires up, the water runs hot for a few minutes, then boiler will shut down, then it sometimes heats up again to shut down again.
I'm guessing it's some kind of thermal switch problem, anyone shed any more light on this?

Thanks in advance.

I have a Ferroli 102.
Had a similar problem & it was a Thermistor. there are 2 of them & it is best to change both.
That was the only problem I have had on the boiler in 8 Years.
JonB

Depends which ferolli it is. Usualy down to the sensors but quite often caused by the fan aswell on modenas.

Thanks for your replies,

I've been having a search round and the thermistors have cropped up a few times.
Not sure what type it is, I have a long serial number and think it's a Falcon. It actually says FER Industries on it, but I know that's ferroli.

The central heating works OK, so I was assuming everything on the "burn" side was ok, tried the usual running the tap at low speed to see if it's the pressure sensor, tried running hot water with heating off.... I did read about swapping the connections over on the heating and hot water sensors to see if that made a difference.... worth a try?