On Oct 22, 1:54 pm, Drake wrote:
Hi,
My Chaffateaux Britony 80 combi boiler has a recurring problem (as
mentioned in an earlier post). A Chaffateaux tekkie thinks its the
diverter valve. It's not easy to get detailed advice from him because
I'm not a registered engineeer.

So how do these 3-way valves work?

It's a 3-way diverter valve, 1 inlet, 2 outlets. The water goes to
either the CH or HW plate heat exchanger.

The actuator is usually a hydraulic diaphragm connected to the HW
supply system. Opening a tap causes a drop in pressure on one side of
the diaphragm, which is pushed by the pressure on the other side,
operating 3-way valve. There are electric diverter valves (e.g.,
Honeywell) but they're far too slow for this application.

There's usually an electric switch on the actuator, which fires the
boiler when the valve is in the HW position.



Electrically, or by some other
means? What sort of fault could cause it to acasionally malfunction
for seveal days on end and then clear up for a few days?

Thank you,

Drake