Honeywell 2 port valve changed but hot water still not heating up without UFH heating turned on

[alimozcan]

I moved into a new flat 3 years ago but the boiler only comes on and heats the water when the underfloor heating is turned on.

I changed the Honeywell 2 port valve today but that did not resolve the issue. See photo showing the new Honeywell 2 port valve that I fitted with a 5 way strain relief connector.

There is also another Honeywell 2 port valve shown at the bottom of the photo but I didn't change that, as I assumed that it was only the one towards the top of the photo that controls the water and heating.

I am assuming that as it still does not work, the issue was not with the Honeywell 2 port valve, and that it is instead with the wiring maybe being incorrectly connected, so I have also provided a photo of that to see if you can spot anything.

Can anyone help? Any suggestions for me to try? Thanks

 

[Exedon]

One valve for heating other for hot water.
With no hot water its probably that valve not working .
Could do with clearer pictures but is the bottom motorised valve connected to cylinder?
If so thats the faulty valve.

 

[alimozcan]

Hi @Exedon , yes the bottom one is connected to the cylinder, so it looks like I changed the wrong one

Thanks for the reply. I'll change the bottom one later today, and hopefully that will mean it will all be ok

 

[alimozcan]

Hi @Exedon and All, I changed the bottom valve as well, and it still doesn't work. I also changed the programmer just in case that was the issue but that didn't work either. So it's not the valve or the programmer. I get hot water when the underfloor heating is turned on but no hot water, if the heating is switched off

I have attached photos of the cylinder showing how it is all connected. I have also attached photos of the wiring, just in case you spot something there that has not been wired correctly.

Can the issue be the diverter which the honeywell 2 port valve sits on? I ask as I didn't change that. I only changed the actuator.

 

[alimozcan]

I should have also mentioned that when the hot water programmer is switched on, the Honeywell 2 port valve connected to the cylinder, does automatically go on, and the lever is loose and can be freely moved from one side to the other, so the programmer is definitely sending a signal, and the cylinder starts making a noise. However, the boiler does not switch on from this, and will only switch on when the heating is switched on.

 

[dilalio]

Firstly, The cylinder 2 port should be wired such that if the overheat stat on cylinder trips, it closes valve and stops boiler firing. This is a safety device and is part of G3 unvented cylinders.

Other than that, programmer may be "opening" the 2 port for the hot water but either the end switch in the valve is not "making" or it is wired incorrectly such that the permanent live (grey) is not "live" or the firewire (orange) is not connected to boiler switched live.

 

[Johntheo5]

I should have also mentioned that when the hot water programmer is switched on, the Honeywell 2 port valve connected to the cylinder, does automatically go on, and the lever is loose and can be freely moved from one side to the other, so the programmer is definitely sending a signal, and the cylinder starts making a noise. However, the boiler does not switch on from this, and will only switch on when the heating is switched on.

(As post #6, above) If you can use a m.meter, with HW only programmed on and cylinderstat calling (loose lever) check for 230V at the grey and orange wires in the terminal box or even better remove the cylinder valve orange wire and check for 230V between it and N (or earth) with the valve opened.

 

[alimozcan]

Thank you both. Really appreciate your advice and photos. I will check this asap.