3 Port valve

[darrenj]

Hi
Now the warm weather has arrived we switched the heating off so only hot water would be called but unfortunately the radiators still got hot.
I searched various forums and the answer appeared to be a faulty 3 port valve so this morning I drained the system, changed the whole valve, sat back, thought what a great job I've done and switched the water on, but the radiators still get hot, I have checked the wiring but it appears correct, I have bled all the rads but they still get hot.

Looking at the various forums I can only see the answer is a new 3 port valve, but as I have done this and I still have the problem I am stumped.

Anyone have any ideas what it could be as I am tearing out what little hair I have left.

Thanks

 

[Steelmasons]

If as you suggest the controls wiring is correct along with replacing the 3 port (correct orientation) then I'm stumped.

 

[picasso]

Could be cylinder return not the last connection before boiler, bit of reverse flow going on ?

 

[dilalio]

Three T's as @picasso - but then this would have been an existing fault, unless you've added any rads recently!

 

[dilalio]

If as you suggest the controls wiring is correct along with replacing the 3 port (correct orientation) then I'm stumped.

Op: check the wiring again... if you just copied the existing - it may have been wrong to start with!

 

[Alec_t]

Same brand/model of valve as before?

 

[Phill Peck]

Oh ffs don't get @Steelmasons started on 3 T's......

 

[Steelmasons]

Oh ffs don't get @Steelmasons started on 3 T's......

Well Phill , you learn something every day in the CC...

 

[darrenj]

It's a different 3 port valve manufacturer, old Danfos, new Salus, I remembered this morning that late last year when I manually put the heating on at the controller then I had to switch the hot water on as well, otherwise the boiler wouldn't fire up, I moved the auto-manual switch on the 3 port a couple of times & the problem went away, was this a coincidence or could the problem be the controller??

 

[darrenj]

Im now not convinced the wiring is correct, this is how I have wired it up, I copied from the old Danfos valve

 

[picasso]

If the blue/red/yellow on 6/7/8 is from the room stat then no the wiring is not right.

 

[darrenj]

I'm not sure if they are from the room stat, is there a way of checking & if they are then how should the 3 port be wired up? thanks for your help with this.

 

[picasso]

Do you have a multimeter and know how to use it ?

 

[darrenj]

Yes & yes

 

[Steelmasons]

White core for MV (term 7) is fed via room stat call for heat , not sure why you have more than two cores into No7 terminal?