Vaillant Boiler problem

mrbios

Got a strange issue with our Vaillant EcoTec Plus boiler. The boiler appears to be ignoring the heating settings set on the Drayton control panel on the wall, and instead following only the hot water settings.

As it's warm at the moment we have the control panel set to off for the heating, but timed for the hot water, however the heating is coming on whenever the hot water comes on. I can even set the hot water to off, and the heating will also go off, then when i turn the hot water back on to timed, the heating comes on too.

It also appears to be ignoring the thermostat settings for the heating, it's a drayton RF+ wireless thermostat, and the receiver by the boiler has both lights out, however I think the top light should be showing a green LED, so i assume something is up with that too.

Has anyone dealt with this problem before or have any suggestions? I'm very new to DIY and learning as i go, this is my first home that we only purchased back in October, the boiler was installed in 2007.

Browntoa

Tried new batteries in the thermostat ?

mrbios

I've just gone through various manuals online, and it looks like the thermostat is fine. I've set a hi and lo temp, set it to 19 degrees (current room temp 22) checked that when i turn the temp above room temp that the green light comes on on the SCR, which it does. So it looks like the thermostat is fine and the SCR is fine and i now have it set at my desired temp.

So presumably it's either a setting on the boiler or the control panel, i've checked the time and date as well as my timed settings on the control panel and they're all correct.

but still as soon as i turn on the hot water, the call radiator indicator turns on at the boiler and heat starts being supplied to the radiators, even though the heating setting on the same control panel is set to off. Very frustrating.

EDIT: I've just done another test, turned the hot water on with the information button enabled, and it says S.3, S.1, S.4 then i've turned the thermostat up so that the call for heating is on (even though it's already on) given it a minute, turned the thermostat down, i see the green light go off on the SCR, but the heating remains on with the hot water. Turn the hot water to off again, and i see S.5 (manual doesn't tell me what the one is, but i presume it's heating off sequence or something, where S.3 is heating ignition and S.4 is burning ignited)

Doesn't look like my boiler is responding to anything but the hot water control basically.

mrbios

Found the problem, in case anyone else comes across similar:
Replace 3 port valve.

I didn't know what one of those was yesterday, but i do now