Thermostat wiring santity check please (Honeywell -> Salus)

Pho

Pho

Pho

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I'm looking to replace my old Honeywell analogue thermostat with a wireless one. Figure it's better to double-check then fry something by mistake ;).

It's in the hallway and it seems silly heating that room when I only care about the room I'm in. I'm thinking about the Salus RT500RT. It's cheap and seems to be rated fairly well; I know the Honeywell CM921 is better but is it really £100 better? If it is I'll gladly swap but in reality I just need it to turn on/off :p.

The thermostat's currently wired into a Potterton EP2002 programmer. The central heating is "on" constantly and controlled by the thermostat and the hot water on the timer, so I'm assuming the thermostat has a constant live. The wiring of the programmer is as follows:

fwfeeEk.jpg
(the mains were isolated!)

Cross-referencing to the programmer manual it looks like:
  • Green/yellow - earth
  • Red - live
  • Blue - neutral
  • Yellow - switched live

Taking the Salus manual and the manual from my programmer I've crudely connected up all the bits:

aD7SWhZ.jpg

Does that look correct? The earth isn't used on the Salus so would be terminated/removed.

I'm thinking it's probably going to be easier to swap the existing thermostat in the hallway with the new receiver instead of just disconnecting it from the programmer and mounting the receiver in the airing cupboard with a new wire. Being in the middle of the house it'll be the best place for signal as well.

Cheers!
 
Wiring looks correct, tho I would trace what looks like your needed cables in that one core, and snip it before it heads off to the roomstat, then feed it into the receiver.

I'm guessing the clock is used as a writing center in the airing cupboard?

Also, spend a few quid extra and get the (plumb centre) centre brand rf stat, it's about £43. It's a rebadged Honeywell, just without the holiday and party function.

Mick

http://www.plumbcenter.co.uk/product/center-radio-frequency-programmable-room-thermostat/

£43+vat
 
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Brilliant thank you very much. All the wiring goes into the programmer with the exception of a tiny junction box that just looks to join up the mains.

Cheers for the heads up on the Plumb Centre one, I read there was a rebadged Honeywell one a while ago but couldn't find what it was again for the life of me. Wolseley (who own Plumb Centre) bought out half the company I work for a couple of years ago so I'm surprised I forgot :o.

Do you know which Honeywell model it "is" out of interest?
 
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From memory it's based around a cmt927, though doesn't have the party, day off, or holiday function, and only has 4 settings per day. Though all the cmt's we fitted nobody used those functions, or all 6 settings per day :)
 
I can't see me using those either to be fair - it'll probably be sat in manual mode most of the time but I like the programmable option if I need it. Doing some Googling and comparing the product manuals I thought it was likely the CM727 in the end :).

I'm trying to get my head around the Plumb Centre/Honeywell wiring diagram - the manual seems pretty poor but then again I'm not an electrician.

I appreciate this is likely a bodged way of doing it but it's the least destructive to the existing wiring. As before, so long as the programmer is set to CH ON (where 4 is live) I'm assuming this should this be correct? (I'd only be making the links I've drawn, ignore the power supply/boiler from the Honeywell diagram)

cjGez7t.jpg

Thanks again :).
 
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Update for future people who find this: I wired it in as per the above diagram and it all seems fine and I didn't electrocute myself :). The only addition was I needed to add a link wire between L and A because my boiler needs 230v to trigger.

Thanks for your help!
 
The Plumb Centre ("Honeywell") one you recommended. It's 20% off on their website as a new customer which handily also applied to click & collect - £40.80 all in seemed pretty good.

Next step is to fit TRV valves all round the house. Don't fancy draining the system down so I think I may have to go for the bung the F&E tank method. These seem cheap and cheerful.
 
Pho said:
Next step is to fit TRV valves all round the house. Don't fancy draining the system down so I think I may have to go for the bung the F&E tank method. These seem cheap and cheerful.
Click to expand...

Yes they are :)

I know they don't come with a lockshield, and cost more, but try and get Altecnic ecocal valves, very reliable and quiet! If not, then any trv is better than none :)
 
Cheers, will add that to my list :). Without going around checking I think all the radiators already have lock-shields to be fair but it was something like 50p more to also get them thrown in - the other benefit of Screwfix is I drive right past the one in Chesterfield on the way home (fellow Derbyshire person!)
 
I live in chesterfield, so if you fancy the ecocal valves then plumb center sell them and are only 2 mins down the same road screwfix is on. Just onto Storforth lane. Can't miss them, buildings big enough!

Mick
 
Ahh, I'm just outside of Belper.

I did look on their website when you mentioned it but couldn't see they sold them, I picked the thermostat up from the Storforth lane store as it happens.
 
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