Worcester Heatslave 9.24 DHW problem

[wales1973]

HeatSlave 9.24 BF 47 311 02

Problem with my heatslave combi boiler. Whenever I draw the DHW, within a couple of minutes the pilot light and burners shut down, which turns off the DHW and CH. The gas supply to the cooker remains unaffected.

A plumber mate is going to have a look but asked if I had a sevice manual or an exploded diagram.

I've tried www.gotoplumbing.co.uk but as I'm not registered there I can't access the pdf files. Does anyone know where else I can download one? Also any thoughts on what the problem might be so I can offer suggestions?

Many thanks in advance.

 

[Agile]

If he is a competent boiler engineer he should not need to manuals to identify a simple fault like yours.

Its likely to be caused by overheated.

Tony

 

[wales1973]

Thank you for the reply, Tony.

What solutions would you generally recommend for the overheating?

 

[ChrisR]

Solutions involve symptoms, knowledge, thought, diagnosis...!
For a start does the heating work?! We aren't psychic, but it's standard problem which probably wouldn't be hard for a boiler man to fix if faced with the beast.

 

[wales1973]

Solutions involve symptoms, knowledge, thought, diagnosis...!
For a start does the heating work?! We aren't psychic,

I thought I'd explained the symptoms in my post. I apologise if I used the wrong abbreviations in my original post:

Whenever I draw the DHW, within a couple of minutes the pilot light and burners shut down, which turns off the DHW and CH. The gas supply to the cooker remains unaffected.

Essentially: Whenever I turn on the domestic hot water, after a couple of minutes, the boiler gets very hot and the pilot light and burners shut down, which turns off the domestic hot water and central heating. The gas supply to the cooker remains unaffected.

I hope that explains the symptoms in a more clear manner.

 

[ChrisR]

DIfferent level of analysis needed - like does it actually overheat?
Can you relight the pilot straight away?
is it easy to do?

We need to be able to work out the exact sequence of boiler internal operations which lead to the trauma

 

[wales1973]

does it actually overheat? It seems to, yes. When the burners light up as the DHW is drawn, the boiler (under the panel) gets incredibly hot to touch and then, after a couple of minutes, the burners shut down and the pilot light goes out.

Can you relight the pilot straight away? It does light but it doesn't stay lit. The only way it does, is to leave the boiler cool down, then I have to hold the grey button in for a couple of minutes, then very slowly leave my finger go - as I'm slowly releasing, then the burners re-ignite and it'll mostly stay lit until I try to draw the domestic hot water again. Also it shuts down in the night if the radiators are on anything over a medium setting.

I hope that helps, and thanks for replying Chris.

 

[wales1973]

Hi, I'm really sorry to bump this again, but just in case anyone who's on this evening may have seen a boiler with these symptoms before, and has any idea of what could be the problem.

When I tried running a bath for my daughter this evening, she stayed upstairs ready to turn the hot water off when it ran cold, while I watched the boiler to see what was happening - the boiler started getting hot from the bottom up and the burners flamed bright red. Then after a couple of minutes the pilot light and burners shut down. The central heating also goes off at the same time.

 

[cjb1971]

is the flu clear of any obstructions?

 

[wales1973]

Thank you for the reply, cjb, but I don't know how to check the flu for obstructions.

 

[namsag]

9.24 circa 1984 it is the calorifier on the front (usually black)that is scaled up prob needs replacing as the water ways are really tight and descaler wont get all the way through(approx 27feet of tightly coiled pipe within). If your really lucky it is the hot water sensor but this is rare

 

[wales1973]

Thanks for that information namsag. Would you have any idea how much a new calorifier costs, and roughly what sort of sum an engineer may charge to fit it?

Christ, I've just had a quick google and the first site I found selling calorifiers, shows costs between £300 and £600, is that right??

 

[namsag]

We had a couple of hundred on contract and 15 year ago they where about 200 quid only take about half hour to change if memory serves me right.. boiler of this age parts are getting short.

Make sure you have the right part number as pretty certain 9.24 electronic and old permenant pilot ones had several different parts

 

[wales1973]

I'll just keep my fingers crossed that it's simple and maybe the hot water sensor. I can only hope.

Do you think that's what Agile was thinking when he first posted? :

If he is a competent boiler engineer he should not need to manuals to identify a simple fault like yours.

Its likely to be caused by overheated.

Tony

 

[namsag]

To be honest wales most people on here have not got a clue what Agile is thinking half the time not even him. He usually forgets that it is a DIY site.

But yes thats what he is getting at