Help wiring a Horstmann Centaur C11

Kashkai

My APT analogue timer died a few weeks back, well the timer part did as it still works when manually switched on/off.

I bought a digital Horstmann C11 as my parents have one and its worked fine for years. However I'm having some trouble figuring out the wiring as my APT has an earth lead, a live, a neutral and a "grey wire" which I'm presuming is another live?.

The Horstmann wiring diagram is like this:
http://www.horstmann.co.uk/downloads/ElectronicDocuments/Central-Heating/C17-InstallationInstructions.pdf

Can someone tell me which wire goes where and confirm that I have to bridge two contacts and also what type of wire will suffice for the "bridging". I'm competent enough to do the job once I know what I have to do in the first place.

Joey the lips

pm sent...

Buford T Justice

Use 2.5 Flex to be safe for the bridge

L, N & E in as described in the diagram 4, for a typical boiler setup. You're not using any wall stats or motorized valved controlled by stats no?

Then but a bridge from L to pole 2, and pole 4 is the live out to the boiler. Make sure there is no mechanical link between pole 2 and 4, as diagram 4, to ensure that the switch can function

Make Sense?

Kashkai

I do have two wall stats that control the two zones in the house by way of two separate motorised valves but these are operated completely independently of the old APT timer, i.e. I can switch on the boiler to heat the water if the two stats are turned off, and if I want central heating I turn the stats on, both times manually. Does this make a difference to how the new timer is wired?

Buford T Justice

Prosperous Dave wrote: »

I do have two wall stats that control the two zones in the house by way of two separate motorised valves but these are operated completely independently of the old APT timer, i.e. I can switch on the boiler to heat the water if the two stats are turned off, and if I want central heating I turn the stats on, both times manually. Does this make a difference to how the new timer is wired?

No. Wire it the way I mentioned above and you will have no change to how you currently use the system, bar a snazzy digital timer.

Kashkai

Was going to wire up my new digital timer today but then I noticed that the wiring in place is grey, brown and black with a separate earth. What is what with regard to the grey, brown and black wires, i.e. live, neutral etc and where do they go on the timer diagram above.

Thanks

Buford T Justice

Prosperous Dave wrote: »

Was going to wire up my new digital timer today but then I noticed that the wiring in place is grey, brown and black with a separate earth. What is what with regard to the grey, brown and black wires, i.e. live, neutral etc and where do they go on the timer diagram above.

Thanks

As said in the electrical forum, the cable used is generally for 3 phase so the sparkie could have done it anyway. Best thing I can suggest is check in the junction box in the boiler and see which way that cable goes to the live and neutral.