DIY Dimmer for Chick Brooder Lamp

An Instructable on making a dimmer switch for your baby chicken's heat lamp so you can control the temperature in the brooder box. No more moving the light around to adjust the temperature.

Make sure everything is unplugged before you begin. Understand that heat lamps and electrical wiring can cause fires. This dimmer is designed for indoor use and there is no consideration given to making it work under wet conditions.

If you need a brooder lamp and heat bulb check with your animal feed store, Tractor Supply or Amazon.

A hardware supply store like Home Depot, Lowes, ACE will have what you need to make the dimmer.

1. Electrical plier - to cut the extension cord and strip the wire ends
2. Screw Driver
3. Three Prong Extension Cord (US)
4. Electric Outlet Gang Box - Get the deep one! A standard one will be too tight.
5. Dimmer Light Switch - get a slider & on/off button version if available
6. Cover Plate for the outlet box - make sure it works with the dimmer chosen
7. Twist On Wire Connector - My dimmer came with them so you may not need
8. Infrared or Outdoor Weather Thermometer - to help you set dimmer

Take some time to figure out where you want the dimmer to be. My brooder lamp had a six foot cord and my outlet was far away so I used the electrical pliers to cut the cord with 5 feet on the male plug side and 1 foot on the female side (any shorter and you'll need another method than a knot to secure the cord).

Using a screw driver (or a drill if there are no knock out holes) pry open two holes for the electric cord to pass through. Go ahead and run the two cut ends of the extension cord into the box. Tie each cord end with a seperate knot that prevents the cord from being pulled back out of the gang box. Leave a couple inches of cord to work with. Using your electrical pliers or a razor blade strip back the plastic ends off each copper wire (black, white or red and green). You only need to expose about an inch or less.

Take a moment to read the instructions that came with your dimmer. Understand that the instructions won't exactly match what we are doing because we are patching in our own electric cord.

See if there is a wire that is used for 2 switch wiring (the red & white wire on my photo). Single pole dimmers meant for a single switch do not have them. If present use a wire connector to cap that wire. You can also cut the wire completely and use a piece of electric tape to cover where it comes out of the dimmer.

Some dimmers use screw connections. If that is the case you'll be screwing the extension cord wires to the dimmer instead of using the colored wire connector caps shown in my photos.

Identify the two white wires on the severed extension cord and reattach them using a screw on wire connector. This is the return power from the lamp and doesn't need to be connected to the dimmer. Make sure no bare white wire is exposed. Use electric tape to cover if needed.

Identify the two green wires on the severed extension cord and the one green wire on the dimmer. Use a wire connector to connect all three (I used a larger wire connector as this is the only 3 wire connection). This is the ground wire that is used to prevent an electric shock.

Pay attention to the male and female ends of your extension cord. Identify the black wire on the male end of the extension cord (that would be carrying in the electricity) and use a wire connector to connect it to the dimmer's black wire.

Now identify the black wire on the female end of the extension cord that would be going to the lamp and connect it to the last remaining unconnected orange, red or possibly blue wire on the dimmer using a wire connector. This connection is what allows the dimmer to control how much power is going to your brooder heat lamp for your chicks.

Inspect the wire connections to ensure there are no exposed wires. Carefully tuck the wires into the outlet box and verify the dimmer switch will fit. Take a moment to think which direction you want a slider dimmer to slide (up/towards the power source is usually 100% and the bottom/towards the lamp is usually the low setting).

Using the 2 long screws supplied with the dimmer attach the dimmer to the outlet box.

Open the cover plate and using the 2 short screws supplied attach the cover plate to the dimmer.

If you have a GFCI outlet (ground fault circuit interrupter) that is commonly found in bathrooms and kitchens use it to test your new dimmer switch with your brooder heat lamp.

Go ahead and plug your dimmer switch into the wall outlet. Then plug the brooder heat lamp into the dimmer switch. Turn on the dimmer and slowly turn it up to maximum and verify everything is working well. Turn the dimmer off and then mark the maximum power and the on/off.

You may hear humming. It should be coming from the heat lamp and is normal. If the humming is coming from the dimmer switch then the wires may be packed in to tightly and causing interference (this happens if you use a shallow outlet box). In either case you should test your setup for a few hours and verify everything is working normally.

Setup your brooder with the heat lamp and dimmer. I like to position the heat lamp to one corner so there are cooler zones for the chicks to retreat to if needed.

Turn on the light for a few hours without the baby chicks present. Take several temperature readings using the thermometer. The IR thermometer makes this very easy to scan multiple temperature readings to find your hot spots. If using a traditional thermometer position directly under the heat lamp on the floor of the brooder cage.

Using the dimmer adjust it until it meets the desired temperature. See chart of what temperature it needs to be for how many weeks old the chicks are. Baby chicks are born with baby feathers and rely on mother hen to keep them warm. This dimmer switch is their replacement mother so make sure each week to adjust it.

Understand that ambient temperature has a huge impact on heat lamp performance. If it is really hot or cold in the room you'll need to closely monitor the heat lamp and adjust the dimmer. Always ensure the chicks have plenty of clean water and cool zones in the cage to retreat to.

Hope this instructable is helpful and that your chickens are happy!