Problem with boiler programmer

[Morten225]

Wondered if anyone could help me out on this one...any suggestions greatly appreciated.

I have (for my sins) an Ariston EuroCombi SX20 MFFICE with manual programmer/timer (part 569294). The programmer/timer is not keeping good time and, generally, running slow - it's actually erratic. Sometimes okay, usually slow, sometimes fast.

Now I imagine that I probably need a new clock/programmer but they're a bit pricey so I'd like some more evidence - particularly since the control PCB was changed a few months back and I'm not sure that it has worked since that point.

So I disconnected the output connections to see if it would run as a clock but it then ran fast. Does anyone know if disconnecting the output connections of a programmer should make a difference to its behaviour. I guess my question is really whether they require a fixed output resistance to drive into - this would seem a bit of a risky approach to use in manufacture since much scope for things going wrong.

I realise that this is a bit of a specific one but any help or suggested tests appreciated.

 

[ChrisR]

Not complicated, it's broke.
You can get an external timer for under £25 - and keep it for when you get a decent boiler!

 

[Morten225]

Not complicated, it's broke.
You can get an external timer for under £25 - and keep it for when you get a decent boiler!

Thanks for the reply

...yeah, I'm sort of coming out of denial about that - it's not helped by being a bit gobsmacked that such a basic device can fail on a 10 year timescale...still stranger things happen at sea.

do you have experience / anything in mind re and external timer - I hadn't thought of that. Are you meaning this kind of thing?

http://www.maplin.co.uk/Module.aspx?ModuleNo=339222
(although the power rating is probably higher than what I need)