Hello all,
Could any1 tell me wot the object circled in pic actually is please?
wot its called,wot its 4,how important it is,etc etc ect?!
Any info u may hav about it at all wud b really helpful.
Fanku very much,
Vikki
(Pic is of my Saunier Duval THEMA F23E boiler)
Sorry the...