re: vaillant turbomax plus 282/2e combi boiler. Problem with c.h coming on when internal timer in 'off' and room stat turned down, disconnected external controls(room stat working correctly) c.h problem seemed to clear, now have intermittent d.h.w problem, cold water running out of hot taps at full flow only luke warm at a trickle, radiators getting warm at same time even when there is no demand for heating, turn on and off fault seems to clear, spindle seems to rotate on divertor valve(only checked this when all working o.k) and modulator all o.k, not sure if divertor valve sticking or faulty electronic board two faults may be connected please help.

grombel, February 2009

sounds to me like diverter valve, the modifed valve has a hole drilled in it about 8-10 mm original valve hole is 4-5mm

Andrew, March 2009

faulty diverter valve, classic fault heating cming on with no call, water pre-heat (green light on front panel) causing rads to come on with no call, boiler thinks its heating small amount of water in secondary heat exchanger but because valve is sticking is heating rads instead, turn pre-heat off by turning hot water dial down min, this will stop heating coming on when it shoulnt until valve is renewed

tojo, February 2009