Baxi 105e instant

[Baxmax]

On power up boiler lights in hot water mode pre-heat off,C.H will not kick in because diff is activated although there is no call for dhw.
Isolate cold supply to boiler and diff goes to rest and C.H wor ks.
There are no leaks on D.H.W pipework and the differential assembly (complete) has been changed.
Any ideas ?

 

[scatmanjohn]

Any ideas ?

No, but i can't wait to see what is causing it

 

[namsag]

Had a normal 105 e they had crossed the hot and cold to boiler during bathroom swap pin came out (dont think all the time though)

Absolutely certain a hot pipe is not leaking under concrete floor

 

[Baxmax]

No pipe swapping,no pipework concealed...........

 

[baxpoti]

Check mixer taps/valves showers?

 

[Baxmax]

No mixer taps,electric shower

 

[Baxmax]

Cold fill washing machine

 

[cross thread]

MUST BE A LEAK, IS PIPWORK RUN IN A SOLID FLOOR? CAN YOU HERE WATER RUNNING THROUGH THE BOILER WHEN OFF?

 

[Vic Spanner]

Next door neighbour illegally tapped into there hot water supply whilst they where on holiday.

 

[Baxmax]

Mmmmmmmmmm

 

[ChrisR]

You, er, looked for dripping taps, puma stlyie?
Stick an iso valve in the hw out??
Use a T and pressure gauge to prove to the guy he has a leak?

 

[sambotc]

Is your central heating pressures ok?

Only thing i can think of if your sure the pipework is OK is a leak between HTG and HW on plate heat exchanger. Or wiring pcb shorting out diff switching.

 

[Baxmax]

Plate o.k no pressure rise, P.C.B changed.....
Somehow the diff pin is being energised.

 

[scatmanjohn]

The suspense is killing me

 

[ChrisR]

You have flow. As I see it you have to prove it isn't within the boiler. Can't see how it can be.

Can you turn a mixer on, like the shower, with a cap on the outlet. Might stop the flow, and if so you can eliminate a few things.