Can anyone help? CH was coming on only on the 1st and 2nd programmed times but would not come on the 3rd programmed time.(honeywell st6400c) Did this for about a week and then heating would not come on at all (Despite this, hot water has been going on and off fine). Just had 3 port diverter valve replaced... heating came on straight away after switching everything back on, i then turned the thermostat down in the hall and as you would expect, the heating turned off. Now i'm trying to get more heat, but heating will not come back on again. Again, HW working perfectly fine. Any ideas?? Could it be a faulty programmer given it was working morning afternoon but not the evening (3rd) set time?
Hi Htg... hope you didnt get me wrong.... i had a valve from a while back as i had problems which turned out to be he PCB on the boiler, so the valve was never used. I guess out of desperation i thought i would change the head, seeing as it was sitting there in its box!!.... Any how, still not working sadly!!!!!! :cry:
I have now borowed a multimeter.... could you tell me what to test so at least i can know whether or not it is the programmer????
As for getting an engineer, i've had 2 out who looked at the system and told me everything was as it should be :? ..... i never saw either of them get a meter out though!!... Thats why i have resolved myself to trying to fix it myself as i seem to be the only one i can rely on just now.