cold tank back filling.

[paulga]

Thanks for all your info, i finally tried sucking water up the hot water vent pipe this morning, to get rid of any air locks, and got a phone call this evening from the customer to say that the over flow hasn't leaked all day !!! (surely not that simple), but now i find myself thinking "how did the air get in there in the first place". Think i'll have to start a new thread.