really need dimmer switch help

[helbycity]

Hello, this is my first post, i would really appreciate any help!

We have a dimmer switch in our bedroom which runs 6 12v 20 watt halogen bulb lamps. Recently is been crackling when we turn it on and the lights surge if turned up high.
We assume the dimmer switch needs replacing (thats the most i could get out of the man in maplin). However when we took off the dimmer switch off to have a look there seems to be a orange plastic casing covering the wires that we can't work out how to remove, any ideas?

Also is there any particular type of dimmer switch we need to buy in order to run all those lights? the original switch is a one knob plastic thing...

Thank you in advance, i very much hope someone can help!

 

[breezer]

try turning the switch around (to see where the wires enter)

are the transformers you have suitable for dimming (not all are)

almost any 250 watt dimmer will be ok

 

[helbycity]

I've been able to find where the wires go in... Do i simply cut them out, strip the casing back and rewire them into the new switch?
There are two red wires going into the L2 port and a black one going into L1...

Thank you so much for all your speedy help!

 

[Chivers7]

Helby they should just unscrew and swap like for like connections into knew unit, there should be no need to cut or strip back.

 

[helbycity]

Thanks chivers7, i will purchase dimmer switch tomorrow and hope for the best!

x