Worcester 28 CDi combi problem with the hot water

[armyash]

Hi guys,

A customer has explained the following to me and wants it repaired, any help appreciated.

28 CDi combi boiler, when there is demand for hot water it's ok for a short period then the boiler will shut off causing the water to go cold. Then it will fire up again and the water will be too hot.

I could ask in work but need to appear to be doing my own research

Any ideas? It is the older model, this guy has had the boiler for 9 years.

 

[tom609]

I guess his centralheating is on if thats the case its the latent heat in the boiler i would say the diverter valve is gettingg tired though could be a sensor check that the micro switch is being proved that will give you some idea then

 

[armyash]

Thanks for the info!

Anyone else have anything they can add? The more suggestions I get the more confident I will feel!

 

[vern]

Hi guys,

A customer has explained the following to me and wants it repaired, any help appreciated.

28 CDi combi boiler, when there is demand for hot water it's ok for a short period then the boiler will shut off causing the water to go cold. Then it will fire up again and the water will be too hot.

I could ask in work but need to appear to be doing my own research

Any ideas? It is the older model, this guy has had the boiler for 9 years.

Check high and low burners pressure's Ash, sounds like its not modulating down, so is getting too hot, then the cycle starts again!

 

[Whyme]

like tom says sounds very diverter diaghram related, if it starts too get get hot that usually says the micro switch is ok, are they the boilers with a little black plastic boot that activates the micro switch? if so make sure the diverter rod is pushing it out far enough to keep the switch ( black box on the end) in long enough to fire. if not its definaitly the diaghram inside.

 

[Roger Welton]

I'd be thinking the plate is probably fouled, providing the m/switch is made

 

[Whyme]

I'd be thinking the plate is probably fouled, providing the m/switch is made

Good call.

 

[vern]

I'd be thinking the plate is probably fouled, providing the m/switch is made

Yep could be if all basics are correct

 

[armyash]

Excellent, thank you all. After a search on the internet these are also the possible faults i was seeing being mentioned. Feel more confident getting the info from this forum though!