Morning, I’m in need some advice. We live in a 7 year old new build with an ideal logic heat 15 boiler with iflo controller and thermostat in the hallway. Hot water tank with expansion tank in the airing cupboard upstairs - no cold water tank. Trying to preempt questions from what I’ve read elsewhere - although it sounds like a problem with the 3 way switch?? Our central heating will only come on when the hot water is active. The thermostat only “clicks” when the hot water is switched on - although it will still “click” after the water has been switched off (doesn’t “click” if the hot water hasn’t been switched on at the same time) HW on - heating works as expected HW off - heating doesn’t work and there is no “click” when I turn the thermostat up/down HW on, heating on at the same time then HW off - heating works as expected Hopefully this makes sense. Do I need an electrician or a plumber? Or any other suggestions as to what the problem is? Thanks in advance Neil
Sorry yes you are right (read too much last night and brain isn’t working fully yet) I’m only guessing from reading across the internet about heating only working when hot water is on. I don’t know what the problem is but I can’t find any information about the fact it all works fine when hot water is active (and then switched off.)
Try this little DIY test. Have the room stat at max. Does your heating come on, it should but if it does not then; Go to the stat on the hot water cylinder. Note its setting. Turn the cylinder stat up, you might/should hear it click and your boiler should come on. OR you could run off some hot water and see if the the boiler now heats the cylinder AND the heating. If it does do both, then the problem looks to be with the 3 port valve. If it is this valve, it could be a couple of things. Could be just sticking and failing to move to the required position. Might be the valve head motor, cost about £20 from SF ( part No. 28670 ) Good luck.
Thank you for your help so far... Hot water on, boiler firing up and tank making noises. Radiators are not warming up. I’ve taken some pics and the only cold pipe is below the iflo zone valve actuator, everything else was hot.
It’s a basic s plan system. A multimeter is probably required to diagnose the fault. When you turn the heating on by itself does the black plastic bit on top of the iflo valve retract inside the valve?
Hi Mike, thanks for the help. Had to wait for the kids to have a bath for the hot water to fire up. The black plastic bit hasn’t moved with just the hot water on.
Turning the heating on by itself at the programmer does nothing. But turning the water on whilst the heating is on somehow jolts the heating side to life. Plausible. Multimeter would confirm.