Viessmann boilers

[kris]

See that too many times with no allowance for the extra expansion vessel on the bigger properties..

 

[cr0ft]

Why would pressure drop if expansion vessel capacity was undersized (without an associated spike to 3 bars when warming up)?

 

[Leo21]

Why would pressure drop if expansion vessel capacity was undersized (without an associated spike to 3 bars when warming up)?

If it's not big enough, it would spike.

 

[hammers4spanner]

Chuck some Fernox leak sealer in there, job done.

Aint that supposed to be PVA??

 

[tamz]

Aint that supposed to be PVA??

Not much difference imo. I'll shove a half litre of polybond in mine next time it drops and see how it goes 😉

 

[tamz]

Technical helplines can be useless, or amazing. Just count yourself lucky you haven't had to phone Vokera, they are always so rude! Maybe go old skool and resort to looking in the manual, the wiring diagram will soon tell you if there is a low pressure cut out or not.

Vokera in Glasgow are/were manned by ex engineers who know their stuff. They might seem a bit curt at times but i know if i was manning the phones for 90% stupid phone calls a day i'd be saying ffs.

 

[Leo21]

Aint that supposed to be PVA??

It does look like it, but I'll stick to Fernox. Just in case.

 

[bright spark]

Has any1 tried Plumb 7 leak sealer. Used it twice. Worked a treat both times