Baxi 105E Instant

[nogoodatfaultfinding]

Right guys,

Gone round to a boiler fault which at first appeared to be the Diaphram on the above mentioned Boiler however boiler also seemed to be overheating, changed diaphram which indeed was knackered.
Boiler Still Overheating only now instant however central heating works perfect.
Changed Plate Heat Exchanger which was all crapped up but boiler still instantly over heating on DHW.
I have checked the 3 port valve switch (Big Electric Block) which apears to be working fine.
Any Ideas?

Thanks
Chuck

 

[fela kuti]

check pump is turning for circulation.is there an air lock in the heat exchanger.
does the flame modulate before overheat if not dhw sensor at fault check the resistance

 

[glasgowgas]

i feel Agile lurking all over this one boy`s...

blah blah Combustion Chamber.....

im embarresed by your post blah blah....

 

[nogoodatfaultfinding]

Turned out to be the differential pressure switch (Which is a brass unit) behind and directly connected to the diaphram.
It was not opening to let out the stored preheat water in the vessel and hence the instant overheating.
Thanks anyway guys.