Quick hack for those with garage heaters
A little background before I dive into how to make your garage heater a bit more smart. I live in Minnesota and it gets cold in the winter. For the past two years I have enjoyed a warm garage by the means of a natural gas heater. This heater has a traditional thermostat to control the temperature which I usual set to a bit over 50 degrees. Enough to melt the snow and allow me to work in my garage with out a jacket.
The one major problem is that the heater has no idea when the garage door is open. It will happily keep on pumping out the heat even when the door has been left open. With kids in the house and sitters the door sometimes gets left open and I come home to the garage heater going.
With a small bit of effort I remedied this by installing a switch on the garage door so the heater does not heat when the door is fully open. The switch is wired so that the heater still has power which is important to allow it to cool down if it was running before turning off. It also allows the heater to still run if I need to crack the door to ventilate the garage for painting or staining projects.
- Parts list:
- Simple button momentary contact switch
- ~50 feet two strand wire
- Electrical Tape
- Some wood scraps and fasteners
The basic wiring idea is to wire the switch onto the common line (W on most thermostats) of the thermostat. In my installation I had the momentary switch set to be Normally Closed, NC, so that by default the thermostat works and only when the switch is pushed in will it break the circuit which lets the heater think the space is warm enough and stop heating.
So to start with lay your wiring from the thermostat with about a foot extra and along the ceiling to the top path of your garage door. At this point you will use your scrap wood to mount the switch in such a fashion so that when the door is fully open it pushes the switch. I just opened my garage door and mounted the boards in place so I did not have to guess. (See the below images as a guide).
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For the wood scraps, one board I fit into the garage door track which had two available screw holes I could mount wood screws through to secure the board. To that board I mounted another at a 90 degree angle to attach the switch. I had a left over arcade button from a previous arcade build that I attached to the switch but this is not entirely needed. Just one more screw holds that in place. The painters tape was just used to hold the board in place long enough for me to screw it in place and also to hold the speaker wires I used. The screws along the back side ensure there is no play in the switch so it will not get loose over time.
After securing the wires to the wall and switch it is time to wire to the thermostat. I forgot to take pictures of this but it is simple enough. Just open up your thermostat and you will see two or three screw posts. W, and Rh, Rc (or just R). Unscrew the wire that is currently connected to W, attach one end of your new wire in it’s place. Then solder or wire nut together the original wire and your second strand of wire from your switch. Close the thermostat up and crank the temperature to test. Ensure the heater turns on with the switch not clicked, and that when you do hold the switch the heating element turns off. The fan may still be running to cool the unit and that is as designed.
A problem you may face is that you wired the switch up to be NO, Normally Opened, instead of NC. This would result in the heater only working when the switch is pushed in. Ensure you have the current momentary switch and have your wires attached correctly so it is NC, Normally Closed.
Now enjoy your warm garage with out having to worry about if you are wasting money when your garage door is opened. Also to the right in case you are wondering, is a picture of my thermostat, again just a standard model nothing special.
