Omega Owners Forum

Chat Area => General Discussion Area => Topic started by: amba on 13 November 2008, 20:58:01

Title: Any plumbers/Electricians that can help ?
Post by: amba on 13 November 2008, 20:58:01
Due to ongoing issue with our central heating system it has become necessary to resite the room thermostat from the landing due to a new radiator being sited close by.The existing system is a coventional baxi boiler and expansion tank..the temperature being controled by a room thermostat.I intend to replace the stat with a wireless unit Drayton RFS 1 ,but I am confused by the wiring on the backplate.
The existing dial unit has 3 wires...Blue-N   Brown-L  pin 3-Yellow/Green
The new unit has 5 connections...N  L   (1)-common   (2)-Heating satisfied or call for cooling  (3)- call for heating.The wiring detail supplied with the unit shows a switch between pin 1 and 2 and states volt free contacts.
My question is ..to what number pin  1/2/3 do I connect the yellow/green wire or do I need some extra wires ...sure it can,t be too difficult for someone in the know.
Title: Re: Any plumbers/Electricians that can help ?
Post by: johnnycboy on 13 November 2008, 21:06:19
Quote
Due to ongoing issue with our central heating system it has become necessary to resite the room thermostat from the landing due to a new radiator being sited close by.The existing system is a coventional baxi boiler and expansion tank..the temperature being controled by a room thermostat.I intend to replace the stat with a wireless unit Drayton RFS 1 ,but I am confused by the wiring on the backplate.
The existing dial unit has 3 wires...Blue-N   Brown-L  pin 3-Yellow/Green
The new unit has 5 connections...N  L   (1)-common   (2)-Heating satisfied or call for cooling  (3)- call for heating.The wiring detail supplied with the unit shows a switch between pin 1 and 2 and states volt free contacts.
My question is ..to what number pin  1/2/3 do I connect the yellow/green wire or do I need some extra wires ...sure it can,t be too difficult for someone in the know.

yellow/green wire would normally be earth, but i would presume who ever wired it originall didn't have any 3 core and earth and used the earth cable as a switched live.

try this, shows you the connections you require

http://www.invensyscontrolseurope.com/NR/rdonlyres/66ED73E9-7EA3-4D7B-9D52-F297A3255118/7443/D1210_RTS.pdf

hth
Title: Re: Any plumbers/Electricians that can help ?
Post by: amba on 13 November 2008, 21:12:42
Thanks Johnnycboy..the detail on the page is an exact diagram of what I have got at present..question relates to where I fit the wire that goes onto pin 3 onto the new Drayton RF1 Digistat back plate SCR..it has 5 possible connections..assume N and L are self explanatory just not sure about this 3rd wire
Title: Re: Any plumbers/Electricians that can help ?
Post by: amba on 13 November 2008, 21:15:43
Am sure you are correct that the Yellow/Green is a quick fix for not having 3 core and earth originaly so use T/E and used the earth with a wire cover..just unsure where on the new back plate to connect it ?
Title: Re: Any plumbers/Electricians that can help ?
Post by: johnnycboy on 13 November 2008, 21:18:06
Looking at diagram it will connect to pin 3.  you may need to check in the termination block where the yellow/green is connected, it should link into your motorised valve.  I'm trying my best to describe what i'm thinking lol ;D. so bare with me
Title: Re: Any plumbers/Electricians that can help ?
Post by: amba on 13 November 2008, 21:19:30
Had a closer look at Drayton diagram and it shows pin1 as common.Would that be the switched feed and the other 2 connecters are not used as they seem to form the circuit when its switched .?so I connect the Yellow/Green wire to Common ??...I hate home wiring
Title: Re: Any plumbers/Electricians that can help ?
Post by: amba on 13 November 2008, 21:23:37
So looking at diagram no (2) it shows 3 pins...if my Yellow/Green wire goes to Motorised valve then I connect it to the pin no 3 on the back plate.
Title: Re: Any plumbers/Electricians that can help ?
Post by: johnnycboy on 13 November 2008, 21:28:49
are you looking at the diagram which came with the thermotat or the one i linked.  if looking at the latter connect it to pin 3.  this will complete the circuit for the heating
Title: Re: Any plumbers/Electricians that can help ?
Post by: Marks DTM Calib on 13 November 2008, 21:39:31
Well 1 and 3 are the contacts you will be using.

A standard twiddly stat also has a neutral connection to pwoer a small heating resistor to add a little hysterisis to the temp setting which is not required on digital stats.

I what numbers are the current wires connected to and what make of stat do you have?
Title: Re: Any plumbers/Electricians that can help ?
Post by: johnnycboy on 13 November 2008, 21:40:57
all i would suggest if you are not sure then dont do it maybe ask someone else to look at it for you :-[.  

technically i can do it, but explaining it is a lot harder.  hopefully someone else will be along soon to give your advice.  :y

all the best johnny

edit: and then arrives Mark :y
Title: Re: Any plumbers/Electricians that can help ?
Post by: Lioned on 13 November 2008, 21:59:17
Sorry to interupt but is not your thermostat (drayton rf1) a 'wireless' transmitter and therefor battery powered.In which case you dont need any wires connected,the clever bit is the reciever at the other end ?
Title: Re: Any plumbers/Electricians that can help ?
Post by: amba on 13 November 2008, 22:04:09
Twiddly stat has only 3 pins(standard Drayton as supplied bt BG)...no 1has blue wire and is marked N ....  no 2 has brown wire and is marked L....only other terminal has the Yellow/Green wire connected to it,but as earlier advised by Johnny this is probably a switched wire as BG didn,t use correct cable.
The new unit I have is a Drayton Digistat RF wireless system  RF 1
this has a back plate of exactly the same size as existing.It has 5 screw block connecters No 1 is N ....No 2 is L......pins 3/4/5 are unmarked but according to instructions supplied SCR is marked as No 3 is Common...No 4 is Heating satisfied or cal  for cooling...No 5 is Call for Heating..hope that helps
Title: Re: Any plumbers/Electricians that can help ?
Post by: amba on 13 November 2008, 22:05:42
Lioned ..well spotted but I need to know the wiring that goes into the bit on the wall that replaces the original "twiddly" turn stat..its the wired in bit
Title: Re: Any plumbers/Electricians that can help ?
Post by: Lioned on 13 November 2008, 22:11:56
I think i get it now.You are actually putting the receiver where the old stat is,and the stat elsewhere due to your new radiator presumably turning it off too soon.
Stat as you know should be sited in an 'average' heat area.The 'receiver' you could site close to your 'wiring centre' if there is one.
As previuosly said you should have 3 core wires,but assuming green/yellow is used as switch line (be sure it is) then it will be terminal 3.
Title: Re: Any plumbers/Electricians that can help ?
Post by: Lioned on 13 November 2008, 22:18:10
I think you may also need to put a link between the live terminal and terminal 1,depending on your programmer.
Title: Re: Any plumbers/Electricians that can help ?
Post by: amba on 13 November 2008, 22:52:50
So I need 4 wires..the existing Blue N and Brown L are in correct place I need to check with a meter if the Yellow/Green is switched .if so I connect that to the new backplate position 3 .I then need to put a 4th wire to the position 1??but what does that connect to??you say a live feed so is that just a straight live
Title: Re: Any plumbers/Electricians that can help ?
Post by: Lioned on 13 November 2008, 23:11:19
http://www.invensyscontrolseurope.com/NR/rdonlyres/8BE57B7E-B03A-4C95-B415-79DAF6208D8F/7546/090793_A.pdf

Is this what you have amba ?

You need to be sure that the green/yellow is going to the motorised valve (either directly or through the junction box).
You can just 'jump' the terminals with a bit of wire from the live to terminal 1.

If you have a wiring unit/junction box somewhere (possibly in airing cpbd or next to boiler why dont you put the receiver there and just make safe the wires sticking out the wall where your old stat is ? Or better still trace them back and disconnect them.

Title: Re: Any plumbers/Electricians that can help ?
Post by: ballcock50 on 14 November 2008, 23:46:18
If you existing r.stat has a neutral wire (blue) then you can fit the rf stat easily first check with a multi meter that the earth cable (green/yellow) is being used as a switched live for the motorised valve. disconect the plug for the heating control or switch off the fused spur, using the continuity setting on the multi meter see if there is continuity from red to gr/ye with the existing rstat turned down (should not be) then turn to max position this should give continuity. The new rf stat then should be wired with the live neutral to their respective terminals a live link to the common on the switch terminal and the gr/ye to the call for heat terminal. but sleeve the gr/ye cable with some red tape for future ref.
Title: Re: Any plumbers/Electricians that can help ?
Post by: Marks DTM Calib on 15 November 2008, 08:02:44
Quote
So I need 4 wires..the existing Blue N and Brown L are in correct place I need to check with a meter if the Yellow/Green is switched .if so I connect that to the new backplate position 3 .I then need to put a 4th wire to the position 1??but what does that connect to??you say a live feed so is that just a straight live

Because the model you have need a short jumper wire from the Live connection to pin 3......as this is an isolated relay setup.....aso the relay common does not have a live feed by default.