Faulty room stat? Not calling for heating alone.
I am hoping someone might have an idea what has gone wrong.
I have been having issue with my heating, yesterday I have had a gas engineer out who has advised the issue is the room stat failing (it’s only been fitted 6 months).
When I call for hot water it works, when I call for hot water and heat it works. But when I call for heat alone it doesn’t work. He says it due to the stat not sending a signal for heat. I’m on a y system with a 3 port motorised valve. The valve sits on w in the off position when asking for hot water it stays in position and turns the pump and boiler on, when asking for heat alone it moved down to mid (not h for heating) but the pump and boiler don’t kick in, when asking for both it sits on mid but the heating kicks in.
Has anyone else had this issue? Can anyone help?
Thank you.
Comments
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Last time I had the problem you describe with 3 port valve was a wiring issue after the (new) programmer was relocated. It was a missing (unconnected) wire at the programmer. Can’t say this is your problem, but that’s a place to start looking.
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I'm not familiar with how 3 port valves work electrically but the fact that the valve does move when you call for heat only would suggest the thermostat is working and there's an issue with the valve or wiring
When you set heat only, can you move the valve manually to the H position to see if it fires up the boiler?
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We’ve been at this for the past two nights to try and figure out. We believe the issue may be with the programmer downstairs. As we have nothing in HW NC which would keep a live when hot water was satisfied or not called for and therefore be able to get heat only. When we fitted the tado we replaced a Drayton lp7112 and a British Gas wr1 which only looked to be wired to the lp112 and nowhere else. So I cannot understand and I’m a little stuck. I’ll try and include photos of the old set up and the new set up.0
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Just realised I cannot upload any photos. If anyone could help I would be very grateful. @GrilledCheese2 ive noticed you have a look of good advice. Can you assist?0
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I can move the valve manually but only fires if requesting heat as there isn’t that live from grey to pass over to white and then orange. One hot water is satisfied the grey dulls and the pump and boiler turn off.0
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That was meant to say if requesting water aswell not heat.0
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If you request the desktop version of the forum you can upload photos.0
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I actually don’t know how to do that I am on an iPhone.0
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see attached screenshot
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This shows a very clear Y plan wiring diagram: https://cdn.brandfolder.io/607DGEMS/as/tqh86npbjjhws5gwkxfncbfh/104172-DIGITAL-WRP01IB01-INSTALLER_MANUAL-TA-UK-00-V2.pdf0
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1) is the old wiring of the programmer
2) is the wiring of the old receiver
3) is the wiring of the tado
when fitting there were instructions of how to replicate the wiring from the lp112 (programmer) but not the wr1 (receiver.) but as the photos show they look to be just wired to each other.
any help for me to be able to get heat alone would be really appreciated.
thank you guys.
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Wiring station, the taped off wires are from a very old wired stat.
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I would start by buzzing out the individual wires to see exactly what’s going where and then draw out the circuit shown in the tado diagram above with your own wires applied . . .0
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Thank you. We have done this. Only thing we are missing is the HW NC. So is my issue that the white is not getting all the voltage it needs to pass to orange and turn pump and boiler on for heat only? Because grey turns dead when HW is satisfied.0
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Yes, you do need HW NC for the mid position valve to operate correctly . . .0
