Honeywell st9100c programmer wont turn on and its brand new

[Deleted member 267285]

Something isn’t right then. Can you post a photo of adjusted wiring?

 

[Tjpace]

Something isn’t right then. Can you post a photo of adjusted wiring?

Yeah mate it's very strange. Worked fine for couple months and then off late it's been on and off and now won't come back on. Was hoping someone would see it and be oh that needs to be done etc or so and so needs to be replaced.

Wishful thinking right.

Soon as I'm back indoors I'll upload a picture

 

[ericmark]

This

from my central heating can look daunting, however that is now a blanking plate, and behind it just a 4 block connector connecting two cables together, and only 2 wires used.

I know that, but would be hard to work out from a picture.

In the main starting point is the motorised valve, the cable is factory fitted, so it is the one device where the colours can be used. With the example above it left the utility room where that programmer was located, as red, yellow, blue, and arrived in the kitchen where boiler is as brown, black, grey. Must be a joint some where, but never found. So to be on safe side, now those control wires only carry 12 volt.

The thing is one can pull and tug a wire on site to see where connected, but can't do that with a picture. But I still took pictures of work in progress so I could return to them if it did not work as intended. But the way forward is to try and make a circuit diagram of what you have, again this is my home. Once I had done that, I was able to see the error, it needed two relays adding, but until one has drawn it out, hard to see the errors.

OK mine was not simple as one boiler served two accommodations, not normal to have two pumps. But I have shown it to show what you need to do for your set up. It takes time, but it allows you to see errors.

 

[DP]

You need a multimeter for a start.
Then you need to identify what sure goes where.
That orange wire almost certainly does not belong there.
Programmer you have is also incorrect ( should be two channel unless you are using a programmable room thermostat god space heating)

Then follow exactly what a y plan termination is.

Looking at your wiring, it looks well suspect. Looking at a picture is not enough to put right what the issue could be. One needs voltage checks etc and understanding of how the three port mid position valve works unless you have a diverter valve whose wiring will be different too

Other option is someone who could talk you through on a phone to correct the issue. For this you will need to be hands on With a multimeter. Did this a while back to assist an end user to fix his Vaillant VCW 242 boiler

 

[Tjpace]

Hi all, thank you all for you professional insights it's much appreciated.

I do have a honeywell dual st9400c as well that I could fit but and wire it as per the label but no one knows where the orange wire should go from the 3 port mis position valve.

If fails we pay for someone to come in and play with it

 

[ianmcd]

I do have a honeywell dual st9400c as well that I could fit but and wire it as per the label but no one knows where the orange wire should go from the 3 port mis position valve.

The orange does not get wired to the programmer, it goes to the switched live inside the boiler usually from the wiring centre, if it worked at one time the wire will still be in the wiring centre, but your programmer is goosed anyway

 

[DP]

Hi all, thank you all for you professional insights it's much appreciated.

I do have a honeywell dual st9400c as well that I could fit but and wire it as per the label but no one knows where the orange wire should go from the 3 port mis position valve.

If fails we pay for someone to come in and play with it

Is the three port valve 4073 or 4044

 

[DP]

Hi all, thank you all for you professional insights it's much appreciated.

I do have a honeywell dual st9400c as well that I could fit but and wire it as per the label but no one knows where the orange wire should go from the 3 port mis position valve.

If fails we pay for someone to come in and play with it

Going by the back plate, cannot see the installation working as the single channel programmer will be voltage free for a start
With white on terminal 4, one has to assume you do not have a room thermostat.
backplate for single and twin Chanel is the same, wiring inside these programmer not the same so what is presented to the backplate not the same.

By look of wires on the back plate, valve would be a 4073 or midposition

 

[Tjpace]

Is the three port valve 4073 or 4044

The brand on expecting of three port valve is a centre

 

[Deleted member 267285]

The brand on expecting of three port valve is a centre

This may be of help then?

 

[DP]

This may be of help then?

Cannot see how the designation of MV is going to help OP as the programmer is single channel voltage free yet the back plate wiring is for twin channel 240 volt switching

Single channel needs 240 on the C terminal- my glasses are getting sorted ATM so that might be the reason I do not see the link to L terminal and terminals 1,2 and 3 would be populated on the back plate and terminal 4 would be spare

Back plate is wired for a two CH programmer. 1 and 3 are hot water calling and satisfied. Terminal 4 is CH calling.

 

[Deleted member 267285]

Cannot see how the designation of MV is going to help OP

Neither can I, but you asked for it, unless you were trying to decipher between a 3 port mid position valve and diverter? Tbh, not much will help the OP apart from getting someone in.

 

[DP]

Your info useful as have not used CB MVs

BTW you reaction score is almost same as mine, you are a lot more popular though