Electrical Gang Box gets hot with 3 Insteon Switches! Normal?

[GDavis01]

At my cottage, I recently had an electrician do some wiring changes eliminating 3 4-way switches to a single gang box with 3 switches. I installed in that gang box 3 insteon switches (1 KeypadLinc Dimmer and Buttons - 2486D; 1 Dual Band SwitchLinc Dimmer - 2477D; and 1 Dual Band SwitchLinc On/Off Switch - 2477S). I had all 3 switches turned on for a few hours this evening and when I went to manually turn them off the cover plate was hot to touch! Is this normal?

 

 

[lilyoyo1]

It can be depending on the load. Especially with all 3 switches on at the same time. Keep in mind they are electronic switches unlike standard dummy switches.

 

Each switch would need to be de-rated due to heat buildup when used side by side.

[mwester]

Was the cover plate too hot to touch?  Or just hot, but you could keep your fingers on it as long as you wished?

 

If the latter, that's normal -- you have two dimming devices which have to dissipate heat -- and the only place to do that is on the exposed metal (aluminum) front plate of the switch itself.  That heat finds its way to the cover plate.

 

You can help to manage that heat in several ways.  First, if the electrician installed a metal box, that'll help a lot -- but if it's plastic, you can't change it.  However, you can change the cover plate to a metal one.  They're getting harder to find, but you can still get them, and in most cases the painted color will match the others well enough that few will notice.

 

You can also separate the dimming devices -- put them on each end, with the switch in the middle.  That will spread out the heat to opposite ends, and keep any one device from overheating.  In fact, if you check the specs, you'll note that the safe load any of the dimmers can handle goes down if the dimmer is installed in a box next to another dimmer.

 

Finally, the amount of heat is dependent on the load.  Switch to dimmable LED bulbs, and you'll create less heat (and save energy).

[G W]

I've had a switch get warm but never hot. Since i switched to LED bulbs my switches don't even get warm.

 

Best regards,

Gary Funk

[larryllix]

Just remember in the summer you may pay twice for the wasted heat too.

You pay to create the bulb and dimmer heat, and you pay again to take it out with A/C.

[Brian H]

Smarthome use to tell users that more than one dimmer next to each other. Had to have their maximum load rating lowered by 200 watts. If separated by a relay type Insteon switch like the 2477S. The maximum load rating reduction was not needed.

 

How hot the cover gets depends on what size or type loads you are dimming and maybe if the 2477S is between the two dimmer type modules.

 

Smarthome did indicate a fairly high temperature value a fully loaded dimmer could reach in the past. So you maybe with in the normal expected temperature. Even though it maybe what you and I think of as too hot.

I am an Electronic Technician and I do not like anything getting too hot.

[paulbates]

To further document Brian's comment about dimmers, here is a snippet from a switchlinc dimmer manual:

 

 Mounting:

Mechanical Mounting Mounts in single or multiple-ganged wall box. Control 200W less load for each immediately adjacent SwitchLinc Dimmer installed. For example, 600 W load control becomes 400 W with another dimmer to the immediate right or left. Use a triplegang box with a mechanical switch in the center to avoid derating.

 

You have reduce the load installed on each dimmer per the directions if you gang them side by side. The warmth is one of the expected symptoms of this.

 

One possible way to address this is by mounting the 2477 on/off in the center between the dimmers as Brian suggested. If that layout works functionally, it still needs to be evaluated for being excessively warm

 

Paul

[IndyMike]

Hello GMD99,

 

As others have correctly posted, dimmer switches generate heat that is a percentage of the power delivered to the load.  The higher the power, the more waste heat generated by the dimmer.  All (95%) dimmer switches generate waste heat in this manner.  This is not something that is unique to Insteon devices. 

 

Since the hot faceplate appears to be new after the rewire, I am guessing that you had traditional (non-dimming) switches installed previously.  If so, these would not have generated waste heat.

 

With dimmers installed, the temperature of your faceplate will depend on many factors that affect the amount of heat generated, and how the heat is conducted away from the switch:

1) # of active dimmers/load power

2) J box type (plastic/metal)

3) Wall type (inside/outside; insulated/uninsulated).

4) Wall sheathiing (sheetrock/plaster/wood)

5) faceplate type (plastic/metal)

 

I made some measurements on the heat generated by a KPL dimmer VS load some years back.  That information is located here: http://forum.smarthome.com/topic.asp?TOPIC_ID=6969&FORUM_ID=9

 

The temperature vs load information should give you an idea of whether there is something "wrong" with your installation.  My guess is that there is not, but I certainly do not want to minimize any concern on your part.  If you believe your temps are running higher than what I am showing in the link, you should absolutely call your electrician.

 

If you are concerned with the heat being generated at the switchbox and/or reliability concerns with the heat in the switches, post back - there are many ways to address this.

[GDavis01]

Thanks to everyone for the comments. After reading the comments I looked at the load and realized that one of the dimmers controlled 10 50W lights and the other controlled 4 50W lights. Fortunately I had a box of 7W dimmable LED's at the cottage so I changed 8 of the 10 on the one switch and all 4 on the other. The result was that the cover plate was only slightly warm after several hours.

 

By the way, the box type is metal and the faceplate type is plastic. The two dimmers are side by side so I could pull them out and reorder them to put the on/off switch in the middle, but given that the faceplate is no longer hot I am no longer concerned and so I will wait until another day.

[jtara92101]

There's nothing specific about Insteon about this - it applies to ALL dimmers. Buy any dimmer at Home Depot, the instructions will have a similar derating statement.

 

Just ain't enough room in the box to get rid of the heat! Plus dimmers tend to be on the large size, reducing air volume. The printed ratings all refer to installation in a single-gang box.

[Guitartexan01]

Just remember in the summer you may pay twice for the wasted heat too.

You pay to create the bulb and dimmer heat, and you pay again to take it out with A/C.

It is rare to hear someone speak so correctly about air conditioning. You're not actually making anything cooler, just moving heat around. Many people do not know this.

 

 

GT