Means they only need one drum of cable at a time? At least this is what I was told by one doing exactly this. When saying it wasn't exactly the correct way, he said as far as he was concerned if it worked that was fine. And subsequently became CORGI registered. ;-)
Ok, a bit more information. I've found the cable that goes from the thermostat downstairs to the heating system upstairs, and posted a pic here:
Many people have said that if, as suspected, my green/yellow is not actually an earth, then the system should be rewired. I'd rather not do that if poss, although now I've found the cable, I wouldn't rule it out. The spaghetti in the above pic shows what a nightmare it would be wiring it in though. Also, personally, I'm not too concerned about the lack of earth as the thermostat explicitly states that it is double insulated and no earth is required.
Other suggestions are that I use a two-wire thermostat. That doesn't help me at the moment as I don't know which wires are which!! I don't know if my green/yellow is actually earth, or maybe a neutral in which case the thermostat I have is fine.
What I really want to do now, is to explicitly establish what my blue and green/yellow wires are. Possibilities for the blue:
1) It's a neutral 2) It's a switched live (call for heat)Possibilities for the green/yellow:
1) It's an earth 2) It's a neutral 3) It's a switched live (call for heat)I have a multimeter if that helps?!
The fact that the heating won't come on if the thermostat faceplate isn't attached may give a clue as to which wire is which, but I can't decipher it!
I've found a PDF of the RTS1 here with a diagram that shows that it is normally open.
Thanks to everyone for their continuing help, hopefully we're almost there now.
Cheers xena
What a nightmare! Do all the wires going into each white block join together inside? If so, God knows what they have done - you have a very colourful mixture!
it's normally open - it's probably drawn in the "satisfied" position to make it clearer where the switch is. You said there was nothing connected to 3 anyway.
You or somebody said that this stat contains a relay. I have a hunch or theory - which may be rubbish - but may be worth checking out. Is the stat
*supposed* to turn on a zone valve which - in turn - turns on the boiler and pump (as per S-Plan in the Honeywell document)? If so, and if there's a relay coil between L & N in the stat, the relay coil may be (incorrectly!) wired in series with the zone valve motor - which may *just* provide enough current to motor the valve to the open position. When you remove the stat from its baseplate, you would break this link, and the zone valve would shut. Can you get someone to stand by the zone valve when you plug the stat in to see whether it does anything? Which cable(s) in your junction box go to the downstairs zone valve, and what are they connected to?On Mon, 15 Nov 2004 10:44:50 -0000, "Set Square" strung together this:
Sounds a good one to me. Looking at the wiring it seems that the g\y is an earth, and that the brown and blue are a live feed and switch wire. To be somewhere near being within the regs I'd get a programmable stat which will be battery operated with volt free contacts. Then you can connect the blue and brown across these contacts. The only other alternative is bodging it together by using the g\y as a neutral instead of an earth.
Cheers SJW. I don't mind doing this at all, if I can be sure that the g/y
*is* an earth. What I didn't want to do was spend out on a new thermostat if all the wires were already there, albeit the wrong colour.
Yes, the the wires inside each white block appear to be connected through the bar inside the block.
Here's a pic of the system:
The wire from the silver box at the bottom of the pic marked "Downstairs heating" is the first black wire in
Thankful, as ever! xena
On Mon, 15 Nov 2004 12:26:44 -0000, "xena" strung together this:
Let me guess, Brown to blue(switchwire) of room stat. Blue to neutral. Grey to live. Orange to boiler live and g\y to earth. The boiler wire is 3rd from the left. It doesn't matter what you do with it, it's still wrong. You've now got two options as to how to correct it, sort of, without rewiring.
Spot on, nice one!!! Cool, happy now. That means that I'm definite that the g/y is earth, and the blue is switched live. Which means I can get the RTS7 (two wire application) and actually know how to wire it! I've seen them on the net for about 15 quid, so that's not bad. Or, like you said, a programmable thermostat, though I'm not sure what one of those is. Gonna look it up now.
Was tempted to swap the g/y from earth to the neutral where the wire from the silver box goes, but would prolly blow system up.
Many, many thanks for all your help :-) xena
Yes - that's the zone valve.
[The other silver one is for the upstairs heating and the white one for the hot water. You have an S-Plan-Plus system. The downstairs zone valve is driven - or should be! - by the downstairs stat, the upstairs valve by the upstairs stat, and the HW zone valve by the tank stat. When any combination of zone valves are open, the secondary contacts inside the valves switch on the boiler and pump].Does the upstairs stat work ok? Is it the same type of stat? If so, see how that is wired and replicate it for the downstairs setup.
Well worth doing - I think we may be getting somewhere.
Definitely! I can't see where they go from the picture - you will need to lift the wires to see where the ends go.
Can you also post the make and model of the zone valve. Hopefully we can find an online wiring diagram for it. If it's like the one in
To be somewhere near
Spotted the Drayton Digistat 2 that I want on eBay. New and sealed, and hopefully cheaper than the £35 I've found so far on the web.
Oh, I'm so chuffed to have finally got this sorted at last!!!
On Mon, 15 Nov 2004 13:34:24 -0000, "xena" strung together this:
Probably the cheapest and easiest option.
How's this for a start,
Hmm, technically known as a bodge, but so is wiring it all in 3 core flex so it wouldn't make it any worse!
Hi Set Square
Think we're sorted now - see other post. I'm gonna get the Drayton Digistat
2, and all will be well.Thanks for explaining the heating system - I'm gonna take a print of the S-Plan-Plus system and leave it for the next owners!!
You're brilliant, thank you so much!
A programmable stat is a combined thermostat and time clock, which enables you to programme it for different temperatures at different times of the day. You would really need one for upstairs too, to be useful. You would then leave the heating on the 'continuous' setting on your main timer, and use the programmable stats to determine when it *actually* comes on and off. You can set different time/temperature profiles for upstairs and downstairs - which can sometimes be useful.
When you've finished all this, you'll have such a wonderful heating system that you won't want to sell the house.
Since it's flex with all the conductors insulated, I'd be inclined to simply sleeve the earth at both ends with red. TW&E is a totally different matter as the earth is bare.
I know it's not strictly correct, but the chances are there are more such bodges elsewhere on the heating system.
This assumes the existing stat doesn't actually need an earth for safety purposes - few do.
Hi Dave
That's exactly what I've done, well, changed the wiring round a little, used the earth as a neutral with black tape over the green/yellow, and the blue as a switched live (with red tape).
I'm keeping an eye out for a programmable thermostat at a tidy price, and if and when one comes up, I'll use that instead so that the system is kosher.
Nice to have a working thermostat at last!!
Cheers xena
On Mon, 15 Nov 2004 18:42:33 -0000, "xena" strung together this:
I wouldn't bother, as it's all wired in flex it will never be kosher without ripping it all out and starting again. If it's all working as it is I'd be inclined to leave it. 'If it ain't broke, don't fix it' sort of thing!
Also, as I said in an earlier post, with your S-Plan-Plus system you need
*two* programmable stats if you are to derive the full benefit from them. The main time switch needs CH to be on the constant setting - with the programmable stats doing the *actual* timing. You can't do that if one of the stats isn't programmable.
I'm not sure if that's true because the timer upstairs controls Upstairs Heating and Downstairs Heating individually, as well as water. i.e. You can program all 3 individually.
I'll likely leave just as it is now, as it's working perfectly and I've sleeved the cables in their correct colour etc.
I would like to say though, how much I've learned from the people who have posted here to help me, and for that I am very grateful.
No, if you have 3 independent channels on your programmer, you're right. I was assuming that you couldn't control upstairs and downstairs separately - apart from the stat setting.
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