Honywell timeswitch fault

[Peter.N.]

Hi folks

A friend of mine has a Honeywell ST9400 time switch on his heating system, sometime after it was installed it started intermittently switching from auto to manual and putting the heating on, he has now had it replaced four times, its OK for a few weeks and then starts doing it again.

The only possible cause I can think of is that it is fitted in the airing cupboard with the hot water tank and I am wondering if its getting to hot. Anyone else experienced ths problem?

Thanks

Peter

 

[simond]

We fit a hundred or so of these a year and have had a couple of failures.

They are designed to go in an airing cupboard.

4 with the same fault? I'd have to doubt it is a programmer fault, tbh.

 

[Peter.N.]

That's what I thought, any other suggestions?

Peter