Y plan problem

[Bunker]

Gents, please help with this odd one...

Old prog and my fitted new one:
HW brings boiler on.
CH does not.
If HW on and CH advanced, 3pv will move over to middle, all good.
If HW then off at prog, boiler stays on until CH off (cant remember if 3pv goes to CH or stays in Middle)

Dual channel prog but no tank stat. Call linked to common on wiring centre, normal links 13/14 an 8/ 16 so whilst not ideal, lack of tank stat should be ok, always used to work.

New 3pv wired in but when CH called for, indicator get stuck in the middle and just keeps clicking.

I tried bypassing room stat with links call/ com in case it was stat.

All wiring looks ok, clearly labelled.

Ive checked all the links, I did find that 3 was linked to 9 instead of 4 to 9 but that didnt help when rectified.

Im a boiler engineer and this sort of thing I enjoy and am reasonably good at but its not my main thing, anyone understand what Ive written?

Thanks

 

[sonray ltd]

Why don't you fit the cyl stat to bring the system up to current standards.

As it is you have no hw satisfied only hw off at programmer.

 

[GasmanxxxR1]

HW priority

 

[yo1]

can that work without a cylinder stat tho?

 

[Ollieg]

you need power to grey wire when hot water off to move valve over to CH and make microswitch.

 

[Leo21]

Must've been wired so heating can't be used without hot water. Also with no cylinder stat, there's no satisfied so three port cant motor over to htg only.

 

[Ollieg]

it can motor over if HW off from programer is wired to grey. As normal 3 port system is.

 

[diamondgas]

If it worked okay before and not now I'd take a look at your wiring again personally 🙂 As Ollieg says, you need power to grey when hot water is off to move the valve to heating only and power down orange to fire up boiler 🙂

 

[diamondgas]

check out this site ... Central Heating Only 🙂

 

[Bunker]

Thanks fellas, Ill have another look, I thought that, as mentioned in the op, where he'd linked the cylinder call to common that would do away with the need for the actual stat (and yes sonray, Ill fit one anyway) and as apparently it worked before, I thought itd be ok and couldnt understand why the 3pv would click in the middle. S plan is much easier to get my head around, Ill get it one day...🙂