Vaillant boilers

[jase158]

Been to 2 radiator jobs this week and both were Vaillant boilers, both customers requested that boiler was filled to 1.8/ 1.9 bar.

one of the boilers come up with F75 code until I put pressure up.

Any ideas why Vaillant boilers are 1.8 bar when other boilers are 1 bar please?

 

[Barry98]

Cos it Says so in the book ?

 

[SafeGasInstall]

i remembre some one saying here is that they have a problem with pressure sensor , and if pressure drops below 1.5bar F75 comees up

 

[jase158]

ok cheers guys, never needed to read the manuals, but will take a look next time.

 

[Terrydoh]

Pressure should be set to 1 bar as normal, I don't know where you got 1.5 from

Customer asked you to fill to 1.5?

Just checked manual. 1 - 2 bar

I would have thought, unless you were struggling to get up to top rads, 1 bar would be preferable to allow for more expansion.

Still could be wrong

 

[GrahamM]

As far as I am aware, most of the vaillants I have worked on anyway, are no different to the norm and I normally go the the usual 1.5 bar. Round about middle of grey area on dial.
If you are getting the F75 fault when just bellow the 1.5 bar the pressure sensor is faulty.

The sensors are very sensitive to dirt and have replaced a few on newish boilers.

Would recommend a magnafilter or the like on any new vaillants.

 

[aquatekplumber]

very interesting discussion

plumbers in Finchley
plumbers in North London

 

[phpaul]

As far as I am aware, most of the vaillants I have worked on anyway, are no different to the norm and I normally go the the usual 1.5 bar. Round about middle of grey area on dial.
If you are getting the F75 fault when just bellow the 1.5 bar the pressure sensor is faulty.

The sensors are very sensitive to dirt and have replaced a few on newish boilers.

Would recommend a magnafilter or the like on any new vaillants.

its a common fault due to the position of the switch on the pipework esp in boilers fitted in lofts .
change the switch and i would recommend changing to solid copper pipes as the rubber sections have proved to be places for dirt to build up and can split.

 

[glenno1]

On some boilers the gauge can be adjusted(baxi is 1)