Biasi Riva HE. They built a boiler you cant service.

[Armitage Shanks]

I diagnosed the problem in 2 mins, magnetic proximity switch not energised for DHW. Ok, lets clean the flow switch. Errrrrrrrrrrr, none of my 65 spanners or sockets fit the top nut, to big for 17mm, too small for 18mm. Out of curiosity I call tech, they say" oh ye, its a problem, throw the whole hydralic block away and fit a new one". The DHW gauze filter is in there and should be cleaned as part of a service.
I did actually manage to remove the plunger assembly in the end after much cussing and removing other components to give more space for a pair of stilsons. Whilst I had the part out I also filed the brass nut to fit a 17mm ring spanner, so in future it will be easy to service the filter and plunger.
Well done Biasi, I wont be recomending any of your products any time soon.
Any other engineers had the misfortune to come across this one?

 

[leelister6]

What about imperial spanners? Would any of them fit?

 

[Armitage Shanks]

No, and like I said, biasi tech confirmed NO SPANNER WILL FIT. Obviously , being european, all other nuts on the boiler are metric.Ive not seen this in 40 years of playing with boilers!

 

[Nostrum]

The least they could have done was sell you a 'special tool' that fit's it! Binning parts for fun, what a joke

 

[leelister6]

Tickle a 17mm spanner with the angle grinder

 

[Nostrum]

Shouldn't have to though, which is the point I guess?

 

[leelister6]

Depends on how many Biasi boilers you may work on! Can pick a set of cheap spanners up for a couple of quid, saves stripping a boiler to get a nut off

 

[Armitage Shanks]

The trouble is, the nut is about 17mm across flats, the thread is about 30mm dia, and a thread that size , left for a few years aint gonna shift with the torque you can apply through a 17mm nut made of brass, thats why it has to be a stilson butchery job. Its a **** design, cant beleive no one else has seen this prob?

 

[Billy Bob Bob]

exactly the same problem on a ariston microgenus HE

 

[SimonJohns]

Couldn't you get a cheap 17mm and grind it to size?