installing a rf programmable room thermostat advice please

[markkram]

Hello all, Looking for some advice,
I am replacing a Lifestle LP111 programmer with a Horstmann HRFS1 connecting to a BAXI 105e about 12 years old. The combi is in the loft and the current programmer is in the airing cupboard.
I intended to keep the new programmer in the same location and use the existing cabling. should get a better wireless signal too.
I have looked at the LP111 and it has 2 twin cables connected to the Baxi.
One cable is connected from the 230v input on the combi into the 230v input of the LP111 which is fed by a 230v supply.
There the other cable is connected from terminals 1 and 3 on the LP111 to the external control terminals 1 and 2 on the combi.There is no link on either end.
When the central heating is on there is no 230v on the external controls. Does this mean it is a Voltage Free system? But the combi manual seems to indicate it is a 230v system on the combi
I think it is VF but I dont want to mess it up as the PCB might blow?

Any advice please?

 

[mikely]

Hello all, Looking for some advice,
When the central heating is on there is no 230v on the external controls. Does this mean it is a Voltage Free system? But the combi manual seems to indicate it is a 230v system on the combi
I think it is VF but I dont want to mess it up as the PCB might blow?
Any advice please?

If you have measured across the output terminals when the heating is on, there will be no 230V as you are measuring across a closed contact. If you measure from neutral to those terminals, you should see 230V. You are correct that the receiver should be connected as shown for the volt free application.