HELP no HEATING -WORCESTER 280-new diverter valve problem

[gnvqsos]

After four days without central heating we thought we had solved the problem.Prior to repair we had hot water but no heating.When heating was demanded the boiler fired for 20-30 seconds before shutting off.I suspected this was a diverter valve fault.I had this replaced and also had a new fan fitted.

The engineer left us with the boiler running.However an hour later the heating shut down and neither hot water nor heating would come on.Opening the hot tap did not cause the boiler to fire up.The heating has now come back spontaneously.the fitter is away for the weekend but suggested I test the diverter valve manually but it seems stuck and I am reluctant to force it.Should a new valve move freely?Secondly can anyone suggest what may have caused the heating to shut down?

The engineer is popping back Monday morning but in the meantime I am scared to call for hot water as I suspect that may have caused the heating to shut down before.

 

[gnvqsos]

I have bumped my reply out of sheer desperation

 

[superdupergasman]

What is the pressure guage reading on the front of the boiler, it may have ran dry and overheated.

The pressure should read 1 - 1.5, if its not fill it upto this level.

There is a red overheat reset on the top of the boiler, reset this and away you go.

 

[gnvqsos]

I am afraid that the pressure gauge reads over 2 bar-thats assuming its accurate.I suppose I could raise the pressure further without doing any harm.

 

[superdupergasman]

No...no no no!!!! I said 1 - 1.5!!!!! 2 is ok...but no more when its cold


Try the red reset!

 

[gnvqsos]

I have sent the nominal pressure up to 3 bar and the heating has come on again.Could the expansion vessel need to be repressurised?

 

[Agile]

Was the entire diverter valve really replaced?

It rather sounds to me as if only the diaphragm was changed and the manifold part may be sticking.

Tony

 

[gnvqsos]

Thanks for your reply Agile.The fitter changed the complete unit and advised me that some people simply replace the top part only causing the manifold to corrode over the long term.I did feel that the new diverter valve did not operate at first and seemed stuck.I did try to manipulateit manually using the underside lever.It now seems to work as we can get both heating and hot water.Secondly I can hear the characteristic whirring of the motor when the hot tapis turned off.

I now find that the central heating temperature on the front fascia no longer clicks.Perhaps this will need replacing.On the positive side the house is warm and we arerunning the boiler all night at a low setting.