dimmer gets hot or has a burning smell.
The dimmer is overloaded, turn off and recalculate the load.
The dimmer is under loaded.
Replace 40watt bulbs with 60watt or
There are electronic transers that are not suitable for dimming.
Electronic transers must be marked "suitable for dimming".
Use a voltage stabiliser with electronic transers that are
noisy or unstable (flicker).