Power loss to boiler Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[mikwillo]

I have had a problem with my Worcester 24i boiler for a few weeks where sometimes the heating comes on and sometimes it doesnt although when it didnt come on, you could hear it firing up like it had come on. There was also a problem with the hot water. Sometimes it would be hot and sometimes it wouldnt.

To get either the hot water or heating to come on I would have to switch the mains swith on and off and torn the dial a few times.

Now I cant get either to work. The fuse light is on but the power light on the boiler is off. Its as if the boiler is completely dead.

Is there anything that I can do or does it look like something has blown?

[htg engineer]

I don't understand why people get faults on their boilers and wait until it goes off completely before asking for help or getting an engineer out.

A relative recently asked me to have a look at his Worcester 24cdi, because like yours it was dead - nothing happening. They then said oh and it's been making a horrible noise for a few weeks, I asked if they could hear the noise outside and they said yes which pointed to the fan.

So replaced a fan for £95, but the fan had blown the pcb which was another £170. So for the sake of getting someone out whent the first fault appeared it cost them an extra £170.

With yours it could have been the pump, not circulating.
Fan not picking up enough speed to operate the air pressure switch
faulty air pressure switch
Sensors may have needed replacing
Diverter

Now it sounds like the PCB, could just be a 2amp fuse has blown or the PCB may need replacing.

To start fault finding you need power to the boiler maybe by replacing the PCB - but if something has blown the PCB installing a new one the same will happen - expensive mistake.

Htg

[mikwillo]

I know, I know. With the problem being intermittent I just thought I'd see how it went. I did take cover out 2 weeks ago but I cant claim in the first 28 days so I either have to try and fix it myself or get someone out to look at it.

What does the PCB look like and how can I tell if it needs replacing?

[htg engineer]

The PCB is located on the back of the front cover behind the thermostat dials etc.

To check the PCB you need to establish what power you have to the PCB and if there's any power going through the PCB to pump etc. There's normally 2amp fuses on the PCB, try testing these first - if you cant test them, replace them. You might be lucky it could just be a fuse that has blown, if it blows again try disconnecting pump then fan etc.

If both fuses are ok, and there's still no power to pump, fan etc then replace the board but remember whatever blew it - could blow it again. I would get an engineer out, explain the faults and let them repair it.

[mikwillo]

[quote="htg engineer"]The PCB is located on the back of the front cover behind the thermostat dials etc.

To check the PCB you need to establish what power you have to the PCB and if there's any power going through the PCB to pump etc. There's normally 2amp fuses on the PCB, try testing these first - if you cant test them, replace them. You might be lucky it could just be a fuse that has blown, if it blows again try disconnecting pump then fan etc.

If both fuses are ok, and there's still no power to pump, fan etc then replace the board but remember whatever blew it - could blow it again. I would get an engineer out, explain the faults and let them repair it.[/quote]

What is the average cost of getting an engineer out to fix this. Am I best going for someone like british gas or a local indepandant engineer? Are there any companies I should avoid?

Thanks for the advice.

[mikwillo]

I look the PCB out tonight and descovered that one of the fuses had blown. After replacing the fuse, the power light now comes back on. The hot water is working again but the heating is not.

Any ideas?

[Lauren Hill]

My Valiant combi boiler has suddenly stopped working, it wasn't giving me any trouble or making any strange noises. There seems to be no power going to it .... I changed the 3 amp fuse to a 13 amp as I didn't have a 3 amp around the house, which I will change but this shouldn't be a big deal right? I'm a bit confused about why no hot water or heating, what can I do to fix it? thanks

[htg engineer]

Change back to a 3amp fuse this protects the boiler. If you get a fault on the boiler it should blow the 3amp fuse if you have a 13amp fuse it'll blow pcb, fan, or pump etc before the fuse.

Any lights showing on boiler ? power indicator ?

Check pressure is between 1.0 and 1.5 bar if it drops below 0.5bar the boiler will not run.

reset boiler ? any manual resets ? check instructions.

If no luck with above - get an engineer

htg