Hot dimmer switches

Status
Not open for further replies.
R

Rawls007

Member
I installed two sets of the Leviton sliding 3 way dimmer switches for a customer of mine (one set of two 3-ways for the living room can lights and one set of two for the dining room light). The switches were working fine after I installed them but the customer called back and complained that on each set one of the switches was getting very hot. The fact that this if occuring on two different switches leads me to believe that they are not simply defective switches. Is this normal?
 
Hopefully, you only used one dimmer and left in one standard 3-way switch for each load. You're not supposed to use two dimmers for each load. Also, you did keep within the wattage rating, right?
 
Levitron dimmers normally include a master and a slave. You should check the products for compatiblity. Levitron has great tech support. Give them a call.

One of the reasons to use Levitron electronic dimmers is to have total control and the ability to dim from every location.
 
FrancisDoody said:
Levitron dimmers normally include a master and a slave. You should check the products for compatiblity. Levitron has great tech support. Give them a call.

One of the reasons to use Levitron electronic dimmers is to have total control and the ability to dim from every location.
Click to expand...

Is this a spoof on lutron/ leviton terminology? If so I haven't heard it. I'd say that normally there is only one dimmer for a set of three ways. The exception would be the master/ slave scenario. And the dimmer does get very warm, bordering on hot.
 
j_erickson said:
I'd say that normally there is only one dimmer for a set of three ways. The exception would be the master/ slave scenario. And the dimmer does get very warm, bordering on hot.
Click to expand...
I agree the slide type dimmers are normal one standard 3 way and one 3 way dimmer. I am guessing that you have the correct dimmers and the appropriate wattage. If you are loading a dimmer to full capacity it will get hot. Dimmers have fins that dissipate the heat. If these are decora style dimmers and are ganged together the fins usually have to be broken which will reduce the wattage capacity of the dimmer.
 
You should only have 1 dimmer on a 3way circuit with Leviton dimmers (you'll have so many call backs for low lighting problems otherwise). Not a set. But that would not likely cause the heating problem. You should add up the wattage of each load and install the proper dimmer for that requirment. Maybe a 1000W dimmer?

Lutron makes dimmers that can be dimmed from multiple locations. These dimmers interact with each other through slave dimmers so that they all have the same dimming level.

Leviton + Lutron = Levitron... An advaced affordable dimmer hybred
 
went on a call about the same dimmer being hot, it was, you could not touch the thing. problem 600watt dimmer, 12 can lights with 100 watt bulbs
 
I'd like to add to Dennis's response. The aluminum faceplate on the dimmer is a heat sync. It's there to help dissipate the heat generated by the electronics inside the dimmer enclosure. All dimmers will get very warm or even hot depending on the load. When you gang dimmers together inside a switch box you have to both snap off the fins on the sides that abut and derate the dimmer by 150 watts (I believe) for each side of the dimmer where you snapped off fins.

So, to give you an example, if you have (2) 600 watt dimmers ganged together in a 2-gang box and you snap off the fins on the left side of the dimmer on the right side of the box and snap off the fins on the right side of the dimmer on the left side of the box they will fit together properly and you will now have (2) dimmers rated at 450 watts each. If your lighting load is greater than that on either circuit the faceplate will get very hot and will dim the lights for a while until the dimmer finally burns itself out.

As others have mentioned, you haven't given us any load or lighting design info so we don't know exactly what you're dimming (with respect to lighting wattage). Also, your description of your installation is a bit unclear. We can't tell whether you've used (2) 3-way dimmers for one lighting circuit or (2) 3-way dimmers for two lighting circuits or if you've used a 3-way dimmer with a 3-way switch at the opposite end for each lighting circuit. Please provide us with the info so that we can point you in the right direction.
 
Just to clarify things a bit, these are two sets of dimmers for two sets of lights. One set operates 8 60 watt can light bulbs and the other operates one light fixture containing four 60 watt bulbs. I went over to her house yesterday and swapped one of the dimmers in each set for a regular 3-way rocker switch, but the dimmer is still getting hot. The dimmer switch is on the side containing the hot lead, and the other 3-way contains the switch leg going to the light.

BTW, the dimmers are decor switches and the tabs have been broke off to make room for others.
 
http://www.residential-landscape-lighting-design.com/lighting_dimmer_derating_ganging.htm



Shows how to derate a dimmer...


WHY DO DIMMERS GET WARM, AND IS THIS SAFE?
The technical explanation. During normal operation, solid-state dimmers generate heat. A solid-state dimmer is roughly 98% efficient-2% of the power is dissipates as heat, causing the dimmer to feel warm to the touch. The closer a dimmer is run to full output and the higher the load (watts) on the dimmer, the warmer it will feel.

This is perfectly normal and safe. Lutron dimmers are designed to the strictest UL safety standard, and can handle their full rated load (a 600 Watt dimmer can handle a full 600W of power*. Without overheating.

*Dimmers that are ganged together in a common wallbox may need to be derated. Consult the product instruction sheet or call the toll-free Lutron Hotline 24/7 at (800) 523-9466 for more information about ganging and derating.
 
Last edited:
I agree with the two previous posts: The fins being broken off forces a derate of the dimmer, when the dimmer is in a single gang box all by itself.

Also, the dimmer being next to another dimmer adds another derate in many manufacturer's instructions.

So, you're getting a double hit, reducing the load handling ability of the dimmer.

The best solution involves carefully researching the manufacturer's instructions (web and print) of that particular dimmer for the derating values, and then do the repair.

You may need to install 1000 watt units, so, after derating, they can handle the connected load.
 
Each side of tabs broken off reduces the wattage that the dimmer can handle by 100 W I believe. So if you broke both tabs, your 600 W dimmer can now handle 400 W. And your one dimmer is dimming 480W.
 
Sorry about the mis-spelling

Sorry about the mis-spelling

I find it hard to believe that most people have not used an electronic dimmers that can be controlled from every location. The master/slave combination is the perfect setup for lighting control. Sure beats the old 3-way and dimmer setup. By the way, It sounds like the OP had two dimmers on the same circuit.
Thanks,
Fran
 
Try using a metal plate ...

Try using a metal plate ...

One thing we have discovered is by using a metal faceplate, you can help to dissapate the heat.

Plastic wall plates tend to insulate, and retain the heat, while metal conducts the heat better.
 
kbsparky said:
One thing we have discovered is by using a metal faceplate, you can help to dissapate the heat.

Plastic wall plates tend to insulate, and retain the heat, while metal conducts the heat better.
Click to expand...


I asked that same question to a Lutron Rep, the answer was NO...
 
FrancisDoody said:
I find it hard to believe that most people have not used an electronic dimmers that can be controlled from every location. The master/slave combination is the perfect setup for lighting control. Sure beats the old 3-way and dimmer setup.
Fran
Click to expand...

I have used the Maestro and they are nice but most customers don't want to spend the extra bucks on these. They ain't cheap and if you add a 4 way the price goes up. Diva dimmers are a nice compromise for most of my customers.
I did an entire house with diva dimmers-- closet lights and all. After we had them all in the owner decided on Homeworks switches in about 25 locations. $300 bucks a pop---- but he didn't want to spend the money on Maestro dimmers originally--- go figure.

FrancisDoody said:
By the way, It sounds like the OP had two dimmers on the same circuit.
Thanks,
Fran
Click to expand...

I believe that is the case----oops. I have seen it before and people were wondering why they couldn't get full brightness when one of the dimmers was set to low. Yikes
 
Status
Not open for further replies.
Top