Vokera Excell combi boiler water overflow?

You tried to top up the system by letting water in. The pressure got high enough to operate the system overpressure relief valve, at around 3 bar. If you are regularly topping up it is very likely that you need to recharge your expansion vessel. Whilst you could do this yourself, it is not difficult, just need a car tyre type air pump, there are no gas safety elements and you can google the instructions., you might prefer to get a gas man to do it (will cost you -may try to tell you its obsolete, cant be fixed, need a new one etc)


Watch the system pressure as the central heating goes from cold to hot - if it increases much you do need to pump the vessel up.

The overflow is the normal, safe, response to what you did (over pressurise the boiler). Dont worry.

c#
April 2011