c/heating system drained + refilled now not working

[dscott@live.co.uk]

Hi there,
i was changing a radiator in the bathroom and drained the system as i needed to move pipes and change valves etc but in the middle of doing this someone flicked the heating on in the house while the system was drained and now the radiators in the house arent heating.the hot water is fine but the boiler is only coming on for a short time then cutting out.the water pump seems fine as its vibrating as normal but no heat to rads.can anyone help? its an oil boiler with an open vented heating system????

[plumbbob]

If the hot water is fine, then the most logical explanation is the system is airlocked. Switch the system to CH only and switch on. Check in the airing cupboard to make sure you have not missed any bleed valves.

If you live in a bungalow and the pipes are in the loft, check up there as there are often valves sticking up in the loft.

[htg engineer]

If you're having problems clearing the airlock, try draining down again and refilling.