worcester 240 hot water problem

[shaka]

Can anyone out there give some advise as boiler doing my head in,try to run bath after about 5min boiler goes off have to relight pilot, try to run bath again works fine for about a few minutes does the same.Re light boiler again this time run tap run for about 20 min hot water so turned off,waited turned on again lasts few mins goes off again, sounds sometimes like kettle boiling,is it just overheating need new stat had gas board last week they tried it worked fine,so need to get bath,might invest in shower, as heating working fine. With thanks.

 

[gas4you]

Sounds like overheat is cutting in and cutting boiler out!

If pronounced kettling noise it could be scaled up heat exchager

 

[shaka]

Thanks for reply should i get overheat stat renewed, dont wnat to realy call gas board out again as it may not cut out again for them.With thanks

 

[gas4you]

You really need an expert to visit you. Whilst anyone here can give professional thoughts none of us has obviously inspected your boiler

 

[shaka]

I will get gas board out again, hope it goes off when there,With thanks

 

[shaka]

Had Gas Board out again look at boiler hot water still cutting out after about half a bath, then pilot goes out they changed overheat stat i believe,also changed the pizo ignition why i don't know,but still got problem,worked as usual for ten mins when they arrived,then cut out,so he changed stat, worked for 20mins while he tested, i tried to run bath happening again,should i just bin boiler as im fed up now i phoned up gas board said have to wait till monday to come and fix. With thanks

 

[Timmyturtle]

Liverpool isnt hard water area is it?

 

[shaka]

No hard water,just dont know why it cannot be fixed properly,Any advise as am going to call someone out yellow pages as gas board no use. With thanks

 

[gas4you]

My guess would still be the DHW heat exchanger scaled up/partially blocked

 

[shaka]

Thanks ill inform engineer if one ever answers phone,are answer machines the norm so called 24 hrs call out dont answer. Ill wait till tmorrow,how much heat exchanger guesstimation. Thanks

 

[ScottishGasMan]

If its cutting out while the Hot Water Is running, Your Most Likely To find its the Domestic Hot water heat Exchanger, (as long as burner Pressures etc are set corect which we'll assume have been checked by the engeneer)

If its Just after the hot water is turned off it could be the pump overrun stat not keep ing the pump running for long enough after.

Is it a 240 With the fan or the balanced flue (big square flue)?

Ive seen this on them before checked everythings ok and found it to just be in desperate need of a service, ie the main heat exhanger was choked so not getting rid of the hot fumes, (balanced flues only)

 

[shaka]

Just to let forum no after all the answers given it was the water to water heat exchanger,guy had second hand one in his van swapped over worked fine he left it in till he orders new one as he said it would cost £157 plus vat for part im happy with that thanks for everones help.