Heating only working when hot water is on

[jsam]

Hi,

Looking for any guidance on what may not have been set up properly please. I bought the evohome connected value pack A (The Honeywell evohome Wi-Fi Connected Value Pack A includes the ATC928G3000 evohome Wi-Fi Connected Controller, ATF800 Table Top Stand & Power Supply, BDR91 Wireless Relay Box, ATF500DHW Hot Water Kit and 8x HR92 Radiator Controllers.) , and have 7 of the 8 HR92s switched on and set up as 7 zones. The hot water kit is set up with the strap-on sensor, and seems to work correctly. We have a Potterton Precision boiler powering the heating and feeding a hot water cylinder, and there is a 3 way valve controlling the hot water flow.

An electrician wired everything up with help from the Honeywell evohome helpline, and managed to get everything working except for the fact that the boiler does not fire up when the heating is on, unless the hot water is also switched on. If the hot water is on it works correctly and hot water reaches the heating system, and I can see that when the hot water is switched off, the wireless relay for the boiler is receiving the correct signal to switch on (green light showing).

The electrician contacted a plumber himself who (remotely) suggested that the 3 way valve could be the problem. We've since had our own plumber out and he's replaced it (and checked the boiler is working correctly), but sadly this hasn't changed anything either. Does anyone know any common issues that might be the problem here? It could be the wiring or could be the system setup, pretty sure it isn't the boiler.

Thanks for your help!

[Richard]

It sounds like evohome has not been configured correctly for a Y Plan system. Has the wiring been completed as per page 47 of the evohome Installation Guide?

Have a look at the video section here for correct pairing of the controller - http://theevohomeshopforum.co.uk/viewto ... =12&t=4061

[jsam]

Thanks very much - I will try again with the setup as I didn't do the 5 minute wait or 2 metre distance originally.

[jsam]

Hi, I've followed the instructions in this video to the letter, but it's still not firing up the boiler unless the hot water is on.
https://www.youtube.com/watch?v=UtbIt1o ... e=youtu.be

I investigated the wiring and worked through matching what has been wired with the diagram on P47. (I'm not experience with wiring so have done my best)

The only inconsistency I can find is that 7 should have 2 wires from it, 1 to the DHW and 1 to the Valve. However, I can only see the 1 wire, and it's to the valve. Is this likely to be the cause of the issue, meaning I should call the electrician back?

I've added photos - I know they're hard to see so it might be difficult to work out the wires, but I've checked each individually and they all seem consistent with the diagram. The black cable goes to the valve, the white cables go to the DHW, HTG and the pump, and the grey cables goes to the fuse and the boiler.

Thanks in advance for any help.
Jo

[Richard]

Jo, have a look at this section to remedy your installation first and then go from there - http://theevohomeshopforum.co.uk/viewto ... ?f=15&t=30