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If people have one complaint about LEDs it tends to be that they have problems dimming them. Dimmability in lighting is a problem that seems to plague all new lighting technology. LEDs are no exception. Since LEDs work fundamentally differently from incandescents and CFLs, there are some terms we should review, most of which will only apply to LED lights. It’s helpful to know how to describe the symptoms you’re seeing with your lighting dimmers. It helps get to the root of the problem more quickly.

1. Pop on - occurs when sliding the dimmer to on and the lights suddenly pop on, essentially not responding to the dimmer until getting to a brighter threshold.
2. Drop out - occurs when dimming the lights but the light cuts out before reaching the bottom of the dimmer switch
3. Dead travel - happens when lamps don’t respond to sections of the dimming process. Pop on and drop off can occur in conjunction with dead travel.
4. Flickering - rapid, sporadic pulsing of lamps when paired with dimmer switches
5. Strobing - lamps that flash rhythmically but less frequently than flickering.
6. Flashing - more sporadic than strobing or flickering, this is when lights randomly turn on and off when paired with a dimmer.
7. Ghosting - when lamps are dimmed all the way down but rather than turning off, they still glow or produce small amounts of light.

There are a few ways to avoid nearly all these lighting problems. The very first thing any lighting professional will ask is, “Are your lights dimmable?” That should be the very first thing you check when experiencing problems with dimming your LEDs.

Another thing to keep in mind is that even if your lamps themselves are dimmable, the dimmer controls you’ve paired with them may not be engineered to work with LEDs. Older dimmers or newer ones that are not rated for LEDs will undoubtedly cause problems with dimming your lamps. All dimmers have life-ratings. If you’re pushing your dimmers, even LED compatible ones, past their useful lifespan, you may begin to experience problems with them.

Ultimately, some LEDs aren’t very good. Buying budget lighting will yield budget quality. SunLake Lighting prides itself on having best-in-class LED lighting. All SunLake’s products are backed by a 10-year warranty are are clearly labeled regarding dimmability so you can be certain you’re getting the best quality product for your money.

If these troubleshooting tips don’t solve your problem, there are some additional points to consider.

Traditional (TRIAC) dimmers, designed to work with incandescent bulbs, require a certain amount of “holding current” to work properly. When dealing with a 40- or 60-watt bulb, that’s no problem. However, LEDs draw significantly less current. For example, SunLake’s 60-watt replacement draws only 9 watts. This isn’t enough for the dimmer to work properly. Typically when paired with an incandescent bulb, the control reduces the voltage as the dimmer is manipulated. Less voltage means less light being emitted by the lamp.

When paired with an LED, these TRIAC dimmers begin to fail. The dimmer has so little current to work with that whatever voltage it does reduce ends up manifesting in the LED bulb as choppy, resulting in flickering, or strobing, or another dimming error.

Of course there are ways to hack this and get the desired result from old non-LED specific dimmers. Generally you can fix LED flickering and other dimming problems by adding an incandescent bulb to the circuit. The higher voltage drawn by the incandescent is often sufficient current for the dimmer to work properly. But this isn't always the case. There are some very real drawbacks to considering this solution.

• For visual purposes, we never recommend mixing different lamp types in the same room or area of a building. You'd want the lone incandescent on the circuit to be in an inconspicuous spot.
• You’ll likely burn through four or five (or many more) incandescent bulbs by the time you need to replace a single LED. You could have a fairly frequent occurrence of having a single burned out bulb. And when the lone incandescent burns out, it will cease to draw current to the circuit, which could cause your LEDs to begin flickering again.
• Generally, while this solution is attainable and seemingly easy on the front end, it can be high maintenance long-term.

Another slightly better solution for adding resistance to the circuit is to buy a "load resistor," or a "dummy load". A load resistor essentially serves the same purpose as the incandescent bulb in the solution described above – it simulates an electrical load, drawing sufficient current to the dimmer switch.

Between adding an incandescent bulb to the circuit and using a load resistor, the resistor is probably the preferred solution, as it's likely to require less maintenance long-term.

The reality though is that by adding the dummy load you will be essentially negating most of the energy saving benefits that using LEDs affords to begin with. Your best bet is to purchase new, LED compatible dimming switches.