Worcester 24i rsf combi boiler not working

[Daz767]

Can anyone advise please.
My boiler was working fine last night, but not today, no heating or hot water.
The boiler comes on but no gas/heater ignition. The pressure is just over one bar, I can top this up with a cold water inlet, I have had to do this quite regularly recently.
Is it time to call an Engineer out, or is there anything else I can try?

 

[swbjackson]

Does it do anything when you call for heating or hot water? Are there any lights showing, flashing or steady?

It could be as simple as pushing the overheat reset but further information required.

Mike

 

[Daz767]

Thanks for replying so quick.
I have checked the reset button and it is ok, thats has happened before.
When I call for hot water or heating it seems like the pump starts up, but no ignition, the pump makes a noise as if working but I am not sure?

 

[Daz767]

Just to add, there is one red light on constant.

 

[diy]

Is the fan running

 

[swbjackson]

The 24i RSF has got the dual heat exchanger so the pump shouldn't run on hot water demand. Are you sure it's not the fan you can hear?

Mike

 

[Daz767]

I have just checked again.
When I put the heating on there is a vibrating sound from the pump as if it is running. I do not get any noise when I turn the hot tap on, but I get the same noise as the heating for a few seconds immediately after the hot tap is turned off.
I am not sure about the fan, can you tell me where the fan is?
Thanks.

 

[gas4you]

At the top of the boiler.

You should hear this kick in a few seconds after the pump, or when the hot water is demanded.

 

[Daz767]

When I call for hot water there is no noise, I cannot hear a fan running. I get a noise from the pump when the hot water is stopped?

 

[gas4you]

Needs to have fan terminals checked for 240VAC, if you feel safe and confident to check live 240AC.

 

[Daz767]

I am confident about checking 240v ac, I work as a print engineer, but I do not know much about boilers, do I have to unscrew and take off the plate which is under the lift off cover to check the fan terminals?
Thanks.

 

[Daz767]

I have checked the terminals to the fan, there is no voltage when the heating or hot water is called for. Is there a fuse on the main pcb?
Thanks.

 

[gas4you]

I believe so. Some pcb's have 1, others have 2. I am not that familiar with this precise model.

Go back to the point you can detect 240VAC then trace it through until you hopefully find the point where it breaks down.

Have you got the manual for the boiler?

 

[Daz767]

With the fan disconnected I get approx 115v ac when hot water is called for. with the load of the fan connected it drops to 0v ac I am not sure if this means the fan motor is faulty or the ac supply? It does not seem easy to get to the under side of the pcb to check either fuse or supply.
I think I will get an Engineer in to check it for me.
Thanks for all your help, I really do appreciate it.
Thanks, Daz.