Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 12-07-2009, 01:50 PM   #1
Newbie
 
Join Date: Dec 2009
Posts: 3
Rewards Points: 0
Share |
Default

Ceiling fan lights dim after being turned on.


Hi,

I recently installed a new ceiling fan that utilizes four 40 watt incandescent bulbs. The fan came with 4 frosted bulbs which I installed. I found that these bulbs didn't provide enough light, so I switched them out with 4 clear 40 watt incandescent ceiling fan bulbs. The lights are connected to a dimmer light switch on the wall. Now when I switch on the lights with the dimmer at maximum brightness, the bulbs are initially brighter than the old bulbs, but after five seconds, it's as if they lose power and dim down about 30% and stay at that level, no flickering or brightening/dimming. This happens every time I turn the light on. I haven't had the fan operating at any time when this happens. Any ideas on the cause?

Goodtwin is offline   Reply With Quote
Old 12-07-2009, 02:06 PM   #2
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,951
Rewards Points: 16
Default

Ceiling fan lights dim after being turned on.


The electrical characteristics of the dimmer mechanism might be drifting due to heat buildup. Some heat is always generated in the dimmer and the greater the load, the warmer it gets.

If you jiggle the dimmer control, do the lights come back full strength?

__________________
Stop wasting time re-adjusting the pattern. Have several lawn sprinklers, one for each pattern.
AllanJ is offline   Reply With Quote
Old 12-07-2009, 04:38 PM   #3
Newbie
 
Join Date: Dec 2009
Posts: 3
Rewards Points: 0
Default

Ceiling fan lights dim after being turned on.


If I turn the dimmer all the way down and then turn it all the way up, the bulbs will go back to their original brightness, but then suddenly dim about 30% after 5 seconds. As I was just testing this, I noticed that after turning the dimmer down and then up, the bulbs make a faint buzzing which ceases when they dim down. Also, when I turn the dimmer all the way down and leave it down, the filaments pulse on and off with a buzzing sound and I can also hear what sounds like a faint tapping sound in the dimmer switch that is synchronized with the pulsing of the filaments. Could the fan be connected improperly? I connected it just the same as the one I replaced.
Goodtwin is offline   Reply With Quote
Old 12-08-2009, 02:45 AM   #4
Mad Scientist
 
Join Date: Dec 2009
Location: Minnesota
Posts: 766
Rewards Points: 0
Default

Ceiling fan lights dim after being turned on.


Modern ceiling fans include a power-limiting circuit to prevent your from using more than a certain total wattage of lights. The symptom you describe is exactly what will happen if the circuit detects more than that set wattage; it will reduce the power to the bulbs by rapidly switching them on and off, faster than the human eye can see.

My guess is that bulbs you put in are actually higher wattage than the originals. Perhaps the originals were "40-watt equivalent"? I.e. they put out the same light as a 40-watt bulb but actually consume less power.

Either that or the bulbs you replaced them with are actually greater than 40 watts. For reference, I think the fan I recently installed at my house has a wattage limit of 180 watts. Anything above that will cause it to either dim, or shut off entirely.

Some weird new energy-saving law, I think.

Hope this helps.
McSteve is offline   Reply With Quote
Old 12-08-2009, 06:23 AM   #5
Electrical Contractor
 
kbsparky's Avatar
 
Join Date: Sep 2008
Location: Delmarva
Posts: 3,368
Rewards Points: 0
Default

Ceiling fan lights dim after being turned on.


Try another dimmer, or replace it with a simple wall switch.
__________________
-KB

Life is uncertain -- eat dessert first!!
kbsparky is offline   Reply With Quote
Old 12-08-2009, 08:48 AM   #6
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,951
Rewards Points: 16
Default

Ceiling fan lights dim after being turned on.


Just for kicks, what happens if you unscrew one (or unscrew two) of the bulbs.

The way modern dimmers operate (by altering the waveform of alternating current to be different from a smooth sine wave), bulb filaments can buzz at certain brightnesses corresponding to certain waveforms.

What is the wattage rating for the dimmer switch?
__________________
Stop wasting time re-adjusting the pattern. Have several lawn sprinklers, one for each pattern.

Last edited by AllanJ; 12-08-2009 at 08:52 AM.
AllanJ is offline   Reply With Quote
Old 12-08-2009, 11:56 AM   #7
Newbie
 
Join Date: Dec 2009
Posts: 3
Rewards Points: 0
Default

Ceiling fan lights dim after being turned on.


I'll try unscrewing a bulb or two and see what happens and I'll also try to find out what the wattage rating is for the dimmer switch.

Might try to find another dimmer switch as was suggested just replace it with a regular switch.

I'll also check the fan specifications for wattage limitation and try replacing the bulbs with 30 watt bulbs, if they are available.

Thanks, everybody, for the suggestions.

Goodtwin is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Thermostat VS Ceiling fan MrShadetree0222 HVAC 38 01-23-2010 03:29 AM
Ceiling condensation icemand Building & Construction 1 12-15-2009 05:16 AM
Ceiling Repairs and Muresco Paint: Seamless Paint Job Possible? Lovegasoline Painting 4 11-25-2009 02:06 PM
Advice for installing ceiling fan Ceiling Fan Man Electrical 5 06-02-2009 04:18 PM
halogen lights fitted into a polystyrene ceiling - safe? jono_wales Electrical 1 03-07-2005 02:52 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.