Central heating cuts out after 30 seconds, hot water is fine

[simonds]

I have an Ideal Classic FF360 boiler where the central heating works for 30-60 seconds then cuts out. The hot water works like a dream. I have bled the radiators but that has not cured the problem. Any help would be appreciated.
Thanks

 

[borntofly75]

I have exactly the same issue. The thermostat is turned to 25 and is calling for heat. Boiler kicks in for 30 to 60 secs and then cuts out. It has been serviced every year and passes.

Any ideas

 

[acecharly]

Sounds like its going to lockout. Is the pump working. Overheat stat. Blockage. to name a few.

Call in an engineer there are too many things to make a guess without having a look.

 

[glenno1]

As said above,it could be a few things and would need to be traced by a competent engineer

 

[Millsy 82]

What boiler is it?

 

[borntofly75]

Ideal classic ff360

 

[Millsy 82]

Does heating and hot water work together?

 

[borntofly75]

The heater and hot water both work. Not sure at the same time. The boiler seems to fire for longer if only heating water not central heating.

 

[TBServices]

I'm guessing your system is fully pumped on a y/s plan (if it isnt, its wrong). If the HW is working that would suggest the pump is working but there is a lack of circulation in the CH system. Possibly due to a blockage or a valve not opening. Id suggest you need an engineer to diagnose the problem properly.

 

[RoryD]

Could be sensors, Blockage and, if it is a y plan the cylinder stat "pulling" the CH to off (obviously if it's faulty). The way to counter this is to turn the cylinder stat right down to off - only temporarily. It's not an everyday occurance but I have known it quite a few times.

 

[borntofly75]

It is a s plan system with 28mm and 22mm valves

 

[RoryD]

It is a s plan system with 28mm and 22mm valves

I'd be checking to see if the valve is making and staying on the microswitch, use a screw driver (insulated)