Alpha 24 Intec no heating. Div valve motor changed 3 weeks ago due to no HW

[armyash]

Hi guys,

Got a job to go to in a little while.

Customer said no HW previously, I changed the div valve motor and all has been fine. Received a phone call tonight now they have no heating. When they turn the heating on, the boiler fires and the temp shoots up and it goes off. No rads get hot.

I'm thinking its a circulation problem as the boiler fires but nothing gets hot.

Any advice before I go?

Thanks

 

[jonnyswamp]

Someone been messing and turned a primary iso off?
Pumps stuffed?
Stuck diverter?

 

[armyash]

I was thinking to check the pump first.

 

[kris]

Sounds like pump or really bad circulation problem , maybe gunked up boiler,,,

 

[armyash]

Just got back. Turned the heating up to max and it all fired up.

They normally have it on timed and they said sometimes the heating comes on and sometimes it doesn't. Could possibly be the programmer is faulty?

HW has been fine just the heating is playing up.

There was a bit of kettling coming from the pump. Bled it but ok.

All working fine when I left but I have a feeling that it will play up again soon.

What would you think was the problem? Timer or pump? Or even diverter valve itself??