Boiler thermostat - replacing

Rideross

 I have an old worcester 24i boiler with a manual timer attached to boiler. 
I was hoping to replace it with a wireless thermostat. I originally replaced it with a salus stat which was like for like replacement but did not get on with it. I have since bought a Duostat RF room thermostat but come stuck with how to wire it up.
pic 2 shows the current wiring to the manual stat on boiler.
Pic 4 shows the Duostat 
Please if anyone can offer advice on how to wire it up I would be grateful. 
Thank you
Ross

southcoastrgi

Just leave the time clock in the boiler & leave on no 1 ie on, wire the new stat as if it was a room stat 

fenwick458

brown from pic 2, goes into L from pic 4
white from pic 2 goes to N in pic 4
put grey from pic 2 into OUT1 in pic 4
and then put a link from L to OUT2 (on the new stat)

thorganby

Rideross said:

 I have an old worcester 24i boiler with a manual timer attached to boiler. 
I was hoping to replace it with a wireless thermostat. I originally replaced it with a salus stat which was like for like replacement but did not get on with it. I have since bought a Duostat RF room thermostat but come stuck with how to wire it up.
pic 2 shows the current wiring to the manual stat on boiler.
Pic 4 shows the Duostat 
Please if anyone can offer advice on how to wire it up I would be grateful. 
Thank you
Ross

You cannot replace the timeswitch with a thermostat.
You should already have a room stat and this is what you are replacing with the Duotherm programmable stat.
The Duotherm receiver needs to be mounted on the wall near to the boiler, not fitted in the boiler casing to replace the timeswitch.
The existing timeswitch is no longer required and the wires connected to the X2 connector in the boiler can be disconnected and a link fitted between CI and CL as shown.

The existing room stat wires need to be disconnected and the Duotherm receiver connected in it's place using a three core cable.
Boiler manual here  https://www.worcester-bosch.co.uk/support/literature/download/release/8716145028/12831
Duostat manual here https://www.tfc-group.co.uk/optimum/instructions/OP-DUOSTAT-instructions-V10.pdf
If this is beyond your capabilities, get a competent person in to do it. 

Mutton_Geoff

Rideross said:

Does your boiler go up to 11?

southcoastrgi

fenwick458 said:

brown from pic 2, goes into L from pic 4
white from pic 2 goes to N in pic 4
put grey from pic 2 into OUT1 in pic 4
and then put a link from L to OUT2 (on the new stat)

Then watch it go bang & you have just thrown your £48 down the drain

Mutton_Geoff

fenwick458 said:

brown from pic 2, goes into L from pic 4
white from pic 2 goes to N in pic 4
put grey from pic 2 into OUT1 in pic 4
and then put a link from L to OUT2 (on the new stat)

Sorry, this is completely wrong advice. You can't replace a timer with a room stat.

As said, leave the timer, switch it to 24 hours then connect your room stat to the room stat "CH call for heat" connections on the boiler.

Older systems work like this:

Room stat - sends demand for heat when room too cold - works 24/7

Timer - sets the times the boiler will run when demanded by heating and/or hot water

Newer systems work like this:

Boiler (timer) - available (not on) 24/7

Programmable room stat - calls for heat at certain temperature at certain times of day (ie replaces old stat and timer)

Leave the old timer in the boiler, set it to be on 24 hours (so it responds to programmable stat at any time)

Set programmable stat to your temp/time preferences.

HW is fed on demand by combi.

Here is a similar situation/set up to yours:

https://www.diynot.com/diy/threads/wiring-hive-on-worcester-bosch-greenstar-25-si-or-30-si.474730/

fenwick458

Mutton_Geoff said:

fenwick458 said:

brown from pic 2, goes into L from pic 4
white from pic 2 goes to N in pic 4
put grey from pic 2 into OUT1 in pic 4
and then put a link from L to OUT2 (on the new stat)

Sorry, this is completely wrong advice. You can't replace a timer with a room stat.

its a programmable room stat, so yeah you can 

fenwick458

southcoastrgi said:

fenwick458 said:

brown from pic 2, goes into L from pic 4
white from pic 2 goes to N in pic 4
put grey from pic 2 into OUT1 in pic 4
and then put a link from L to OUT2 (on the new stat)

Then watch it go bang & you have just thrown your £48 down the drain

why exactly will it go bang?

southcoastrgi

fenwick458 said:

Mutton_Geoff said:

fenwick458 said:

brown from pic 2, goes into L from pic 4
white from pic 2 goes to N in pic 4
put grey from pic 2 into OUT1 in pic 4
and then put a link from L to OUT2 (on the new stat)

Sorry, this is completely wrong advice. You can't replace a timer with a room stat.

its a programmable room stat, so yeah you can 

Not in this case you can't 

fenwick458

and would you care to explain why?