Heating wont turn off

[MartyMalabu]

Hi sorry been out to lunch

engage the top off the proggrammer into the top off the back plate at about a 45 degree angle then hinge it down

Tried that, it wont go without significant force. I will try again.

 

[matt1e]

Hi sorry been out to lunch

engage the top off the proggrammer into the top off the back plate at about a 45 degree angle then hinge it down

Tried that, it wont go without significant force. I will try again.

you have to hook it over the lugs

 

[MartyMalabu]

OK managed to get programmer back together
A repeat of the tests with the single suspect wire between T1 and the Orange connector replaced.

1. The system is was wired normally except that all 5 valve wires were removed.
2. All measurements were done to both neutral and to earth and they were the same in every case.

Sometimes it's easier to trace these types of faults with the valve out off the equation as the internal circuitry in the actuator can lead to confusing results, so to check the wiring disconect the valve wiring then

turn both stats down and turn HW and CH off at the programmer
now check for 240v at the terminal that the grey would connect to
reference this terminal to neutral and earth to make sure that polarity is ok it should be 240 ish in both cases (this is important)
now check that the terminals that are normally connected to valve white and orange are at 0v

Grey 240v
White 0v
Orange 39v

Grey 240v
White 0v
Orange 0v

now turn HW on at the programmer
same tests should be same results

Same as above including the 39v

Same as above including the 0v on Orange

now turn the cyl stat up
the terminal that valve grey connects to should now be 0v and terminal orange should be now 240v (the boiler should now be firing too)

Grey46v
White 0v
Orange 240v
Yes - boiler fired up

Grey34v
White 0v
Orange 240v

leave HW on and cyl stat up and turn on ch
check that terminal white is still at 0v

Grey 50v
White 80v
Orange 240v

Grey 40v
White 80v
Orange 240v

then turn room stat up
terminal white should now be 240v

Grey 55v
White 240v
Orange 240v

Grey 40v
White 240v
Orange 240v

now check that turning off CH at programmer removes voltage from terminal white

Grey 44v
White 0v
Orange 240v

Grey 34v
White 0v
Orange 240v

next leave both HW and CH on and both stats turned up...

Grey 50v
White 240v
Orange 240v

Grey 40v
White 240v
Orange 240v

... then turn the cylinder stat down
in this position the boiler should stop firing and both terminals that feed valve white and valve grey should be at 240
valve orange should be 0v,

Grey 240v
White 240v
Orange 39v

Grey 240v
White 240v
Orange 0v


So changing that wire has improved two of the tests.
What next ?

Thanks.

 

[matt1e]

have a good look at the cable connecting the cyl stat because it looks as though voltage is bleeding from the stat common
are you sure it is not physically damaged?
disconnect the brown from term 6 on your block
you will prob find that the stray voltage on the grey will disappear

 

[MartyMalabu]

have a good look at the cable connecting the cyl stat because it looks as though voltage is bleeding from the stat common
are you sure it is not physically damaged?

It has been crushed slightly where it had been tucked under the metal band that holds the cylinder stat to the cylinder, but apart from that it seems OK.

disconnect the brown from term 6 on your block
you will prob find that the stray voltage on the grey will disappear

I did this and the voltage did not go away, but I found a similar problem with the voltage on T2 as I did with T1, so I have replaced that wire too. Now that wire is showing 0v, unless I connect it back into the connector block(HWOFF) where it shows 30v. I disconnected the T2 wire from the connector again and measured HWOFF signal alone in the connector block and it shows 30v.

 

[twgas]

Now disconnect the HWOFF at the prog end, test the wire again (both ends), try connecting a flying lead to HWOFF at prog to test that connection.

 

[MartyMalabu]

Now disconnect the HWOFF at the prog end, test the wire again (both ends),

0v with the programmer removed, at both ends.

try connecting a flying lead to HWOFF at prog to test that connection.

I did this and refitted the programmer
HWOFF flying lead at programmer : 240v HW turned off, 0v HW turned on
HWOFF at "grey" connector still 37v, even though it is NOT connected to the programmer.

The cylinder stat is now totally disconnected.

Any ideas where to go next.

Thanks again for your time.

 

[twgas]

Try disconnecting the other programmer wires (HWON and CHON), one at a time, at test again.
Did you check the wiring at the boiler?

 

[MartyMalabu]

Try disconnecting the other programmer wires (HWON and CHON), one at a time, at test again.

I found that with the programmer removed, and HWOFF disconnected on the programmer backplane, linking HWON to Live puts 30v on the end of the HWOFF wire near the programmer. I guess this suggests that these two wires are interacting somewhere between the programmer and the connection block ?

Did you check the wiring at the boiler?

Sorry twgas, I didn't because I was awaiting clarification, I think I asked you should this be done with the fault present, or after a power reset ?

Bearing in mind what I have found above, do you think this still needs to be done ?

If this is a problem with these two wires, I dont see how an easy repair can be done without ripping off plasterboard and floor panneling. Not nice, I would have preferred a replaceable unit to be at fault.

I guess one option would be to use one of the signal wires to feed an unswitched live up to the connection centre and then fit a new programmer in the airing cupboard, with new HWOFF/HWON/CHON wiring.

Your thoughts please chaps. And thanks again for your input.

 

[twgas]

Try disconnecting the other programmer wires (HWON and CHON), one at a time, at test again.

I found that with the programmer removed, and HWOFF disconnected on the programmer backplane, linking HWON to Live puts 30v on the end of the HWOFF wire near the programmer. I guess this suggests that these two wires are interacting somewhere between the programmer and the connection block ?

Looks like it, if the HWOFF wire is disconnected both ends.

Did you check the wiring at the boiler?

Sorry twgas, I didn't because I was awaiting clarification, I think I asked you should this be done with the fault present, or after a power reset ?

sorry, missed that post, although you could have used your initiative, and done both.

Bearing in mind what I have found above, do you think this still needs to be done ?

Still worth doing, with previous results you've had there's no telling what we might find out.

If this is a problem with these two wires, I dont see how an easy repair can be done without ripping off plasterboard and floor panneling. Not nice, I would have preferred a replaceable unit to be at fault.

We all prefer easy repairs but, unfortunately, these things happen. It is not very often that replacing cables is an easy, straightforward task.

I guess one option would be to use one of the signal wires to feed an unswitched live up to the connection centre and then fit a new programmer in the airing cupboard, with new HWOFF/HWON/CHON wiring.

I dont think that is a viable solution, I'd need to mull it over for a while.

 

[MartyMalabu]

Did you check the wiring at the boiler?

Sorry twgas, I didn't because I was awaiting clarification, I think I asked you should this be done with the fault present, or after a power reset ?

sorry, missed that post, although you could have used your initiative, and done both.

OK, would you mind giving me some more info on what I need to do with this (not sure what the pin out is) :
//www.diynot.com/network/MartyMalabu/albums/8578/34367

 

[MartyMalabu]

I guess one option would be to use one of the signal wires to feed an unswitched live up to the connection centre and then fit a new programmer in the airing cupboard, with new HWOFF/HWON/CHON wiring.

I dont think that is a viable solution, I'd need to mull it over for a while.

What is it about that proposal that is not viable twgas? Obviously repairing what I currently have would be preferable.

Thanks

 

[twgas]

I guess one option would be to use one of the signal wires to feed an unswitched live up to the connection centre and then fit a new programmer in the airing cupboard, with new HWOFF/HWON/CHON wiring.

I dont think that is a viable solution, I'd need to mull it over for a while.

What is it about that proposal that is not viable twgas?

It all depends on the number of cable 'cores' you have, and, if the existing cable is damaged do you really want to use it.

Obviously repairing what I currently have would be preferable.

I certainly do not dispute that.

 

[twgas]

Did you check the wiring at the boiler?

Sorry twgas, I didn't because I was awaiting clarification, I think I asked you should this be done with the fault present, or after a power reset ?

sorry, missed that post, although you could have used your initiative, and done both.

OK, would you mind giving me some more info on what I need to do with this (not sure what the pin out is) ://www.diynot.com/network/MartyMalabu/albums/8578/34367

Just re-read the post about checking at boiler and can't see any mention of "pin out", I don't know where that came from or what pin you are talking about.

Have you checked the wiring at the boiler?
To do so

• 1 turn HW and CH off at prog and check for 240v @ permanent live 0v @ both pump and switch lives.
  2 discon, and make safe, the pump live - switch on HW (cyl 'stat up) and check for 240v @ all 3 cons on boiler but 0v on the pump wire (the disconned end)

 

[MartyMalabu]

Just re-read the post about checking at boiler and can't see any mention of "pin out", I don't know where that came from or what pin you are talking about.

sorry, forgive my terminology. I was asking if you knew which terminal on the boiler was which. i.e. which is unswitched live, pump switched live, boiler switched live. If you dont know off hand that's fine. I will have to try and find out.

Thanks