Y plan motorised valve problem

[steveboy]

The mid-postition valve is wired up and works correctly ,( standard ten block connector )my problem is this ,when the central heating goes off the mid- postion valve stays in the on position ,(is this the normal condition?)thus causing the valve to get hot , I read somewhere that this is not good for the valve as it can cause them to burn out . Does anybody know how to wire it so at the end of the heating period the valve de-energises and closes off.

P.s there is a yellow wire from the boiler which i think may or may not be something to do with it ?

cheers and many thanks

steveboy:

I have checked and double checked the wiring and followed the "Y" plan wiring to the letter, the yellow wire from the boiler comes from the "CH on" on the boiler control board ,

the wiring diagram that came with the boiler shows it going to "T8" but then the boiler won`t turn off even after the programmer has finished ,i then connected it to "T4" ,and now the boiler still runs even though the room stat is satisfied, but will turn off at the end of the programmed time !

any shed of light would be of great help.

Before i persue this problem , Is it normal for the valve to stay in its last postion when the programmer has finished or SHOULD IT RETUREN ON ITS SPRING TO CLOSED POSTION I.E PORT B FULLY OPEN ?

 

[kme]

If the 3 port valve is staying energised, then the phrase "wired up & working correctly" is obviously wrong!!!!!

The "yellow" wire could be anything - without testing the system, it is difficult, if not impossible to diagnose the fault.

n.b. on the central heating thread, there are drawings of various layouts, with the correct connections. I`d start by checking YOUR wiring against these????

HTH

KME

 

[revjames]

Dont forget the motorised valve will have a switch return to tell the controller what position it is in. Well I was on a job this week and there were 2 separate valves (2 port) and they had switch returns on.

 

[Lurch]

If the 3 port valve is staying energised, then the phrase "wired up & working correctly" is obviously wrong!!!!!

Not neccesarily. The valve can be live during any state of the heating controls settings. They are quite simple, but very complex devices 3 port valves.

If you want to remove all power from the valve when the heating is off you need to start adding relays into the system. I'd turn it into an S plan though, much easier\reliable.

 

[SPECIAL LOCATION]

The mid-postition valve is wired up and works correctly ,( standard ten block connector )my problem is this ,when the central heating goes off the mid- postion valve stays in the on position ,(is this the normal condition?)thus causing the valve to get hot , I read somewhere that this is not good for the valve as it can cause them to burn out . Does anybody know how to wire it so at the end of the heating period the valve de-energises and closes off. P.s there is a yellow wire from the boiler which i think may or may not be something to do with it ?

cheers and many thanks

steveboy:

I have checked and double checked the wiring and followed the "Y" plan wiring to the letter, the yellow wire from the boiler comes from the "CH on" on the boiler control board ,

the wiring diagram that came with the boiler shows it going to "T8" but then the boiler won`t turn off even after the programmer has finished ,i then connected it to "T4" ,and now the boiler still runs even though the room stat is satisfied, but will turn off at the end of the programmed time !

any shed of light would be of great help.

Before i persue this problem , Is it normal for the valve to stay in its last postion when the programmer has finished or SHOULD IT RETUREN ON ITS SPRING TO CLOSED POSTION I.E PORT B FULLY OPEN ?

Welcome to the forum Steveboy.. Guinness

This may be of some help to you...

http://www.diyfaq.org.uk/plumbing/controls/midpositionvalve.htm

Or this...

http://www.gasheating.co.uk/Mid-Position-Valve.html

saves time trying to explain something some has already done...

They both have a description of how the 3port valve works..

and some pictures!

 

[SPECIAL LOCATION]

... Does anybody know how to wire it so at the end of the heating period the valve de-energises and closes off. P.s there is a yellow wire from the boiler which i think may or may not be something to do with it ?

cheers and many thanks

steveboy:

I have checked and double checked the wiring and followed the "Y" plan wiring to the letter, the yellow wire from the boiler comes from the "CH on" on the boiler control board ,the wiring diagram that came with the boiler shows it going to "T8" but then the boiler won`t turn off even after the programmer has finished ,i then connected it to "T4" ,and now the boiler still runs even though the room stat is satisfied, but will turn off at the end of the programmed time !

any shed of light would be of great help.

Just thinking further on this one..

FIRST OF ALL WORD OF CAUTION:-

the wiring colours & terminal designations are not a hard & fast standard rules set in concrete!

They typically are guidance as to common arrangements..

But providing you understand what bits are on each side of the various switches/thermostats/vales etc..

It is just a matter of following the switching Logic to get power to your boiler and various pipe vales open in the right sequence!

Some of these "wiring centre" J/Boxes with a 10 or 12 way connector strip inside them are crap!

You sometimes don't have enough room for all your cables or to get the lid on.

or some terminals with NO wires on.. others trying to cram 5 or 6 neutrals into a connector block that is too small!!!

A more appropriate adaptable box with larger connectors (or even crimps)

and a suitable label / note with colours cables used etc.. can be better.

You may need to trace out your actual wiring with a meter to confirm Exactly what is going where?

That said..... Yellow wire? Is this part of a 3-core & Earth cable..

e.g. Red/Yellow/Blue & Earth conductor.?

as above the colour is NOT the information needed.. Its where its connected to & from.

With a Y-pan you will normally have THREE live supply triggers via the valve to boiler& Pump

• Heating ON - which will go to the white wire on the valve typically via a room thermostat & terminal 4 on you "junction box thingy"
  
• Hot water ON - which will go to the boiler & pump Via a cylinder thermostat and a joint onto the orange valve wire connected after the cylinder stat. Typically terminal 8 on your "J/Box thingy"
  
• Hot water OFF - which will go to the grey wire on the valve and a strap connection to one half of the cylinder stat two-way switch. Typically terminal 7 on your "J/Box thingy"
  

J/Box thingy recognised technical description!!!! ROTFWL

So if your yellow wire is C/Heating ON sounds like its going to the wrong place IMHO?

As terminal 8 is normally the live feed to boiler & pump..

which doesn't normally come direct from the programmer..

i.e. some sort of thermostat control in between programmer & boiler! :|

I would put yellow back onto terminal 4..

Which is where C-Heating on normally goes to.

Have you got your Hot water On & Hot water Off wires reversed?

I bet I have got some of my description ar5e about face on this post..

But I did re-read me homework and I think its correct????Blushing:|

Guinness

 

[steveboy]

Thanks for the welcome ,this is the 1st time i have ever been on/in a forum and i must say all the info that is within it is very good !!!Cheers for that info , I will reverse the grey and white wires to see if that makes a difference ,like i said earlier i don`t know if the valve is supposed to stay in its last postion after the programmed time as elasped ,or should it wind back to its default postion using its spring ?

The yellow wire is part of the 4core cable coming from the boiler red to live blue to nutruel black to "T8" and yellow to "T?" the yellow on the boiler side is connected to the "CH on" tab so i just presumed it must go to "T4"