Dave Plowman (News) wrote:
In article
,
4square wrote:
In an open-vented system, anyone know how much water is used, by
evaporation from the tank, if any? level in my tank dropping slightly,
maybe slight lk somewhere I suspect.

Servowarm used to fit open systems with no water supply the tank. You had
to top up with a bucket when needed. Usually every few years. When mine
was open vented I used to turn off the cold water supply to the ball valve
- in case of a leak or whatever when away. Don't think I ever had to top
it up between inhibitor changes etc which required a drain down.

How often should inhibitor be changed?