3 replies to this topic

[Whitegoods]

On Saturday morning our trusty Zanussi FJ1214/B (914837001) was in mid-wash when the house RCD tripped. There wasn't much else running so we suspect the washer was the cause. My wife reset the RCD and the wash cycle continued to completion. She opened the door as normal but the clothes were still wet. I have since tried just to run the spin cycles (both of them, short and long) with no clothes in the washer. The pump runs but the drum does not spin. It does not even try to spin - nothing. It rotates immediately and strongly during the wash and distribution cycles. But it sits stationary through the spin cycle. By a process of elimination I have concluded that it's the timer. But before I order a new one (if I can find one) or set about fixing this one (if I can't) I'd really appreciate someone checking my thinking. So here goes:

1. It's not the motor. The machine turns fine at normal speeds - immediate start and 100% reliable. It doesn't run at all and doesn't seem to try - not even a twitch - on spin. Thumping the motor (as you would with worn brushes on a car starter) doesn't help.

2. It's not the speed controller. This uses only one triac (is this right ?) which is not dead, otherwise the motor wouldn't run at low speed. If the speed-set resistor network is on the controller pcb then I suppose it's possible that a resistor there has failed. But this is low-voltage circuitry (is this right ?) which tends not to blow resistors and furthermore it's not clear how that could have tripped the house RCD.

3. It's not the pump or its piping or the filter. When the pump runs the water comes out very strongly. When it's finished running there's no water visible in the drum. There was some fluff etc in the filter but not a huge amount - certainly not enough to block the flow - and the problem isn't fixed by cleaning the filter. Furthermore the problem isn't fixed by disconnecting the air pipe from the pressure sensor and that's how the rest of the machine would know that there was a problem with the pump/water piping.

4. It's not the pressure sensor or its air pipe. The washer fills and empties reliably and to the right level. I disconnected the air pipe and tried blowing down it. It didn't seem to be blocked. Blowing into the sensor I could hear the three switches click in sequence as the pressure rose. There was a report in another thread of a high-resistance leakage fault in the sensor which meant the machine thought there was still water in the drum when there wasn't. But I metered through the sensor's contacts at zero pressure and I could find no leakage. And the metering showed reliable electrical switching as the pressure rose.

So if it's not the motor or the speed controller or the pump or the water piping or the pressure sensor or its piping then all that's left is the timer, right ? If I've made some mistake in this then I'd really like to know. If you can recommend any further checks then that would be really welcome too. And if you could point me towards a wiring diagram for this machine then that would make it much easier for me if I decide to go any further with the fault-finding.

Thanks in advance,

Whitegoods

[Washerhelp (Andy)]

Something in the speed control pcb or timer could have blown when it tripped the electrics. The main suspect is the motor but not the only possibility. You would need to test the machine for low insulation using a megger which puts 500v dc through the machine. Without doing this you could get exactly the same problem even if you managed to replace the correct faulty part.

I wouldn't recommend fitting a timer. They are usually extremely expensive and you get no guarantee with them. I would estimate that about 90% of the time a user fits a timer it's been misdiagnosed. To be honest, with this fault I would either get an engineer in or scrap it. DIY repair could end up throwing a lot of money down the drain.

[Whitegoods]

OK, time to 'fess up. I was so convinced it wasn't the motor. It worked so reliably on 'wash' and so not-at-all on 'spin'. I got an engineer in (he's just left). He changed the brushes and cleaned the commutator. It works fine now. You live and learn.

Whitegoods

[Washerhelp (Andy)]

Many thanks for your update.