Nest system CH working HW not....

[Hadleigh]

Well if the heat link clicks you must have power to 11, So there should also be power to the heat links 2 common connections (2+5). Points to check:
Is the hot water cylinder already up to temperature?
Has terminals 2 and 3 in the wiring centre been linked together?
Are the links set as per the instructions in the wiring centre lid?(for biflo)

If all the above has been done, do you have a multimeter? Can you post photos of the wiring centre and heatlink wiring, might be able to spot a wiring error quickly.

Cylinder is cold haven't had HW on today, links between 2 and 3 are in place.

I will try dig my multimeter out of the shed.

Checked all the wiring links as per the lid and there correct, there also extra links that were there prior to start these are from 3 to 12, 6 to 12, 9 to 3, 10 to 15 and 12 to 13 are any of these to be removed?

Thanks for all your assistance so far it is much appreciated!

 

[flameport]

even pushed L through from behind programmer upstairs

Why do you still have the old programmer?

Any other ideas? Probably easier to call out Nest installer you think...?

Definitely.

 

[Hadleigh]

even pushed L through from behind programmer upstairs

Why do you still have the old programmer?

Any other ideas? Probably easier to call out Nest installer you think...?

Definitely.

The programmer is now redundant as all have been disconnected behind it and also disconnected upstairs in control box. Will eventually remove it completely and put a blanking plate on it downstairs.

 

[Echo the husky]

3 should not be linked to 12, other than that it should work...

Any other ideas? Probably easier to call out Nest installer you think...?

Definitely.

Does sound like it.

 

[Hadleigh]

3 should not be linked to 12, other than that it should work...

Any other ideas? Probably easier to call out Nest installer you think...?

Definitely.

Does sound like it.

My bad 3 is connected to 9 and nothing else.

Can't seem to dig out my multimeter so when it gets light tomorrow I will. What conditions should be present where for when I locate my multimeter?

 

[Hadleigh]

3 should not be linked to 12, other than that it should work...

Any other ideas? Probably easier to call out Nest installer you think...?

Definitely.

Does sound like it.

Cable going to hear link port 4 (think it's SAT) had come out with all my fumbling around! HW is now working.

When I pump heat up for CH above current temp the boiler doesn't kick in (heat link is clicking every one or so seconds if this is any clue?).

I have it goes from terminal 2 on the heat link to 11 (permanently live) and terminal 3 on the heat link going to terminal 9 (heating on).

 

[Echo the husky]

AC volts, one probe on the neutral terminal for all tests.
heating only
240V on:
2,3,4,6,7,8,9,11,12,13,16

Hot water only, cylinder stat calling for heat
240V
6,10,11,12,13,14,15

Hot water only, cylinder up to temperature
240V
7,10,11,15,16

Hot water and heating on, cylinder calling for heat
240V
2,3,4,6,9,10,11,12,13,14,15

Hot water and heating on, cylinder up to temperature
2,3,4,6,7,8,9,10,11,12,13,14,15,16

Any random voltages that are substantially below 240V should be ignored.

 

[Echo the husky]

Cable going to hear link port 4 (think it's SAT) had come out with all my fumbling around! HW is now working.

It sounds like there is a wiring error, the hot water will work with the wire in heat link terminal 4 disconnected (the heating won't work properly though)

When I pump heat up for CH above current temp the boiler doesn't kick in (heat link is clicking every one or so seconds if this is any clue?).

It sounds like the live supply to the heat link is not permanent and that when heating is switched on it is cutting power to the heatlink, the only way i can see this happening is if you have accidentally connected heatlink L to heatlink 1 instead of heat link L to heatlink 2

I have it goes from terminal 2 on the heat link to 11 (permanently live) and terminal 3 on the heat link going to terminal 9 (heating on).

That is correct.

It does sound like you will need to call someone in though...

 

[Hadleigh]

Cable going to hear link port 4 (think it's SAT) had come out with all my fumbling around! HW is now working.

It sounds like there is a wiring error, the hot water will work with the wire in heat link terminal 4 disconnected (the heating won't work properly though)

When I pump heat up for CH above current temp the boiler doesn't kick in (heat link is clicking every one or so seconds if this is any clue?).

It sounds like the live supply to the heat link is not permanent and that when heating is switched on it is cutting power to the heatlink, the only way i can see this happening is if you have accidentally connected heatlink L to heatlink 1 instead of heat link L to heatlink 2

I have it goes from terminal 2 on the heat link to 11 (permanently live) and terminal 3 on the heat link going to terminal 9 (heating on).

That is correct.

It does sound like you will need to call someone in though...

Turns out the clicking is coming from the 2 port valve (sounds very similar clicking noise to the Nest heat link). Does this give any other clues as to what might be going wrong for the CH?

 

[Hadleigh]

CH works when HW is on, and HW works independently.

Just need to find out why CH won't work on it's own (just the two port valve starts clicking/ticking -possibly this is faulty?)

Looks like all the wiring is now correct but will check correct voltage in correct terminals when I dig out multimeter tomorrow just to triple check.

 

[Echo the husky]

possibly faulty microswitch in the valve actuator, but check there is 240V on the grey wire of the valve when heating is on and hot water is off.

 

[Hadleigh]

possibly faulty microswitch in the valve actuator, but check there is 240V on the grey wire of the valve when heating is on and hot water is off.

No fault with microswitch just me being a complete idiot, when terminating 4 back into the nest link it looks like 5 and 6 went into wrong terminals (cupboard has no light and it was getting late in the evening poor excuses ha ha).

It now works a treat CH and HW independently and together when needed. Thank you for all the time you've put in walking me through it, it is much appreciated.

Time to head to screwfix for blanking plate for where programmer used to be. It's ok to terminate any cables from programmer to upstairs onto a dead connector block or just cut of the shiner and push back into box?

 

[Echo the husky]

Put unused wires in spare connector block for future use.