Some Insteon Switches very hot... Normal???


Active Member
A few of my Insteon Dimmer Switches are very hot to the touch. Others are not. The ones that are, are hot even when the switch has not been on for a while. Some are in dual gang boxes, some are not.

Is this normal and is it something I should be worry about?

I have seen reports of hot switches before but never could figure out a pattern. Is it only switches in multi-gang boxes that get hot? What do you mean by "not been on for awhile"? Are they hot first thing in the morning after being off all night? Are they all regular bulbs, no halogen or other weird stuff? When they are on do you run them at 100% or dimmed? Are any of them running more than 400W of lights?
I had a similar overheating problem with a Insteon 1000W dimmer in a 3 gang box along side 2 other Insteon relays. The overheating got to the point that the dimmer started to miss on/off commands from my controller and soon after the relay switch next to the dimmer began to fail as well.

After investigating and doing a little more research on dimmers and heat I found the cause of the problem to be:

- the switches were in an exterior wall and this was in the heat of the summer
- this was a plastic 3 gang box that was not a good conductor of heat and hence not a good radiator to disipate the heat
- the box was installed tightly between 2 studs
- insulation was packed around the gang box

To sum this up, my dimmer was generating heat, the exterior wall was already warm due to the outside temperature, and the plastic gang box was unable to effectively disipate all this heat.

To correct the problem I installed a metal gang box and removed some of the insulation from the wall directly around the box. Smarthome replaced the damaged switches and I have not not had a problem since. Note that the dimmer does still get pretty warm but the face plate and screws are not too hot to touch anymore. This has been working now for 10+ months. I am running the dimmer load at about 720 watts and both relays are running about 300 watts each so overall all I am probably at or above the recommended capacity of the 3 gang box.
Also remember the derating instructions whan more than one is in the same box and next to each other. I believe it is 200 watts per added switch.
The dissipated heat from the switch is a factor of the wattage being controlled. The more lights, the hotter it will get.