DIY Doctor UK DIY Forums

Hi. Total beginner. Just installed a two gang dimmer. This one...

http://www.screwfix.com/p/lightwaverf-2 ... teel/9999r

It's installed in a place where there was already a double dimmer switch. The two lights being controlled are on two different circuits at the main switchboard. Not sure if that affects what I'm about to say. Anyway...

One of the lights only has one switch, but the other has another switch out in the hallway. The one where there's only one switch was dead simple. Just two wires, but obviously the other one had three wires because (not sure of the terminology here) the third one needs to talk to the other switch.

So, I installed it all as per the instructions on the web, but it's working rather weirdly. When the switch in the hallway is on the new double dimmer works. When it's off, it doesn't.

Any ideas what I've done wrong..?

I only have one idea... The switch in the hall is old (and actually not a dimmer*), whereas the new one is quite modern. The connectors on the back of the new one are in the X-S-L format whereas the one I replaces was in the L1-L2-C format. I wonder if that makes a difference?

Anyway, all thoughts welcome. Thanks in advance :)


*when we moved in, this light had two switches. One dimmer, and one regular.

Yes, you have brought a switch which is not suitable for your needs.
In the information listed it clearly says " (slave dimmer required for 2-way)

The way I read that, it will not work in 2 way with another normal switch, so you either
1) Have to change the other switch that controls the light to a slave dimmer

2) Take it back and get a normal 2 gang dimmer

3) Do away with the 2nd switch and use the "control it from you phone function"

I think I've got this figured out. I think? A bit of googling reveals that LightwaveRF use a different wiring system for 2-way switches to everyone else, relying on a 'signal wire'. I guess that means you can't have the two different systems on the same circuit.

Anyway, all thoughts still welcome...

Hi Mr White... Thanks for your reply, much appreciated :-)