Urgent help needed - Swapping Room Thermostat

[smokey]

Hi all,

I was hoping someone on here could give me some advice on replacing our relly old room thermostat, for a new Honeywell digital stat.

Here is the wiring for the old stat:

and here is our new stat connections:

Can you please tell me where the wires from the 1st pic (old stat) go into the new thermostat

Many thanks in advance

Erran

 

[D_Hailsham]

More info please!

Make and Model of old stat
Make and Model of new stat

Then I can look in my crystal ball

 

[weareleeds]

red to a blue to b yellow to c

 

[smokey]

More info please!

Make and Model of old stat
Make and Model of new stat

Then I can look in my crystal ball

Old stat...............I dont have a clue, only recently moved in and it never had a cover. What you see is what you get lol

New stat is a Honeywell T6620B1008 or DT200

How certain are you weareleeds? I have read other posts on here which suggest that I just terminate or sleave the blue (N) cable.

Many thanks for your help guys

 

[namsag]

Your old stat is a satchwell and you are right new one does not have a neutral so red to A and yellow to B . Do not connect the blue or the earth don`t snip them right back incase you ever change stat and new one needs them

 

[kirkgas]

i would follow weareleeds reply, i believe some old stats don't have a neutral but newer ones require it to work properly, if you connect safely but connect to wrong connections it won't work so it could be trial and error but looking at the pic and weareleeds post i think he/she is spot on,
PS the he/she is an attempt to be politically correct and in no way meant as a slight on weareleeds

 

[namsag]

Ignore both kirkgas and wearlad it has no neutral ,3 connections live (common),normally open and normally closed

 

[smokey]

Thanks for your input guys, I am having trouble with conflicting stories.

Does this datasheet help?

http://europe.hbc.honeywell.com/products/pdf/en0r8528uk07r0704.pdf

Thanks once again

 

[namsag]

yes it confirms what i said. NO neutral .

 

[gasisexpensive]

turn off electric and check it is off. discon and terminate blue wire so it is safe,(as previously said blue wire is not req)
personally i would terminate this blue wire in the wiring center.
red wire to A
yellow wire to B
ensure 3 amp fuse is in spur/plug.
there will probaly be an earth wire on the old back plate,this is also not req and also needs to be terminated in a safe manor.

 

[simond]

Crikey, this is where the forums let you down.

Ignore Weare and Kirk they are talking cobblers and you may burn out the new stat relay, becasue you will put a dead short across it. Sometimes people give advice with absolute confidence when they can't find their arse with both hands.

Do not connect the neutral or the earth under any circumstances. Red and Yellow to A and B (doesn't matter which way round) as suggested already by those qualified to answer. Fair play to them.

 

[kirkgas]

ok simon, make your point don't hold back, i have already been politely put in my place over this one by earlier post, have another kick why don't you.

 

[simond]

OK. One more time.

You got it wrong.

nernicky noo naa!

 

[namsag]

What i will say kirk is you where replying to other topics for ages after i had said what should be done it gave you time to relook at wiring and you could have came back an said something, we all make mistakes the secret is holding our hands up. And i am not having a go at ya

 

[kirkgas]

fair point, i should have checked first as the idea of posting is to assist others not confuse them, i don't think you were having a go, and even my reply to simon was a bit tongue in cheek, i was wrong so consider my hands well and truly up, much better to keep someone else right at the expense of my already fragile ego!!!!!!!
i will stick to plumbing & gas in future, oh no as a plumber i risk the wrath and condemnation of the special one, (as he probably calls himself on the sticker on his pencil case)