where'[s the link?
Hosting issue is probably down to licensing..
Hosting issue is probably down to licensing..
Replaced motorised valve now nothing works!
- Thread starter dubmuffin
- Start date
Click on my username, the diagrams are in my album, or below as have just worked out how to show them.
Have a testing breakthrough this morning. This image shows the readings I am getting. The pump does seem to be on when the boiler is on but not the timer, and I am getting 150v across the blue and brown pump wires (terminals 3 & 4 on the right). I am puzzled by the 100v reading on my unmarked (possibly supply) cable. I think it should read 0v until the MV operates.
We have never touched the left hand wiring, but I have now put both greys in term 2 on RH side. MVs still not working when stats on.
I look forward to all your expert thoughts on this.
Luckily the sun is out so solar heating giving me a 32 deg shower if I dare!
Hi, the first thing I noticed was the three blues in number 4.
These should almost certainly be in number 5 which you have marked as 0V.
So at present the pump and the 2 valves are not getting their neutral connection. That at least explains why there wasn't the full 240V across the pump and why the valves wouldn't motor into position.
If and when a valve does move over, it's orange should switch to the same voltage as that connected to the grey wire, ie 240V, which fires the boiler and runs the pump.
These should almost certainly be in number 5 which you have marked as 0V.
So at present the pump and the 2 valves are not getting their neutral connection. That at least explains why there wasn't the full 240V across the pump and why the valves wouldn't motor into position.
If and when a valve does move over, it's orange should switch to the same voltage as that connected to the grey wire, ie 240V, which fires the boiler and runs the pump.
Hi Jackthom,
The 3 blues are in no 4 which has a 240v feed, I moved the grey from no 4 to no 2 with the other one. Now I can confirm that when I switch each valve to manual, the boiler fires but then switches off because I believe there is an issue with the pump circuit.
The pump is on continuously perhaps because of the 100v on term 3 on the left? Why 100v and from where?
If I isolate the "supply" cable (3,7,9 left) the pump stops, and when I test the disconnected wires, there is no voltage present even when the boiler or/and timer are on.
When connected, it there is 100v on the brown and black and 240v on the blue - 7L - which is there because of the Room stat black which has a permanent 240v
If I test across the blue and brown of the pump (3,4 on right) with the "supply" disconnected I get the expected 240v.
The left side wiring looks wrong to me but it has always been like that!
I hope I am explaining this OK
I think you've mixed up some of the wires as you changed the valve.
The way to avoid this ...next time... is to snip off the old cable leaving a coloured tail in each terminal then remove these tails one at a time replacing them with the new same colour wire. Too late to tell you now...sorry.
You need to get hold of a 2-valve wiring diagram and start again I suspect.
iirc Honeywell have diagrams on their boiler controls website.
The way to avoid this ...next time... is to snip off the old cable leaving a coloured tail in each terminal then remove these tails one at a time replacing them with the new same colour wire. Too late to tell you now...sorry.
You need to get hold of a 2-valve wiring diagram and start again I suspect.
iirc Honeywell have diagrams on their boiler controls website.
Have you moved the three blues fron the right side of 4 ?
They are neutral connections for the 2 valves and the pump and they should all be in connector 5.
With any luck the system might then work.
They are neutral connections for the 2 valves and the pump and they should all be in connector 5.
With any luck the system might then work.
More info:
That 100v is still confusing me.
Surely there should not be a voltage reading on that wire until the valves operate?
When I plug the boiler in there is a small click (relay or something? preparing it to operate if necessary)
If I remove that pesky 100v brown wire from 4L then plug the boiler in, there is no click.
This might not be relevant
That 100v is still confusing me.
Surely there should not be a voltage reading on that wire until the valves operate?
When I plug the boiler in there is a small click (relay or something? preparing it to operate if necessary)
If I remove that pesky 100v brown wire from 4L then plug the boiler in, there is no click.
This might not be relevant
I will try this, (those 3 are the worst to reterminate) Can you explain further. My understanding was that these should be a constant live which they are getting from 4L. If I connect them to 5R, the corresponding reading on 5L is 0v
Thanks for your patience
The browns are live aren't they, so the blues are sort of "switched lives " and need to be on the 0v? Off to try, running out of time tonight tho...
Well, Jackthom, thank you so much. It just seems completely obvious now, I had a eureka momnet once you pointed that out to me,errr, twice - never one to do as I'm told the first time
. Changed those blues and heating is gurgling away.I've learnt a lot about the system now anyway so I'll know so much more next time I need to replace something (the OH perhaps!)
Isn't it nice when it all starts working. 
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