rads cold no indication of boiler fault HW fine (pls urgent)

[toocold]

Hi All

Bit of an urgent one being that time of year and can't get a plumber out until after xmas even on an emergency callout

I have just tried to turn on my CH for the first time this year as I have a number of guests coming for xmas dinner but even after an hour all the rads are stone cold and no fault codes coming from the boiler just a constand "c" indicating a call for CH is on and the boiler does sound like it's on also HW is fine and hot straight out of the tap

Any idea what it could be

Further info

Boiler is an Ideal Combi 35
Rad valves are all open on TRV's and lockshield
Flow pipe is warm return valve is hot but rest of the pipe is cold

Any further info needed please ask, desperate for guests not to to spend xmas in several layers

 

[toocold]

Sorry quick update and free xmas blooper for heating engineers

Had an aladdin isolation valve closed hidden behind the wahing machine from when we had a leak, inlet hose must of grabbed it when we had the washing machine pulled out to be fixed

still suprised the boiler didn't fault when there was no circulation

 

[John.g]

With CH selected on, if you open a hot tap does the boiler just fire up and provide HW?., when you close the hot tap does the boiler just stop firing?.

Have you got motorized zone valves?.