Window fan: Bypassing thermostat with a button

In summary, the article discusses a method for bypassing the thermostat control of a window fan using a button. This modification allows users to operate the fan independently of the thermostat settings, providing more direct control over airflow and cooling in a space. The process involves wiring a button to override the thermostat, enabling continuous operation regardless of temperature conditions.
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DaveC426913
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Bought this cheap window fan. Want to bypass the thermostat with an on/off button.
I bought this window fan for my work shed. Installed it on a nice, mild day. Next day fan wouldn't work. Almost took it back to the store before realizing the day was much colder. The fan is on a thermostat - one that's probably set for summer, not winter.

So, I want to be able to operate it in near-freezing temps. Rather than ripping out a perfectly good thermostat function, I'd like to just press a button to bypass it.

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Plaque on back says it draws 120V and .7A. It has 2 independently-controlled fans, each with 0-1-2-3 settings. (Hopefully, the .7A is at max output). Thera are very small, low speed plastic fans.Here is the thermostat. It appears to be first in line in the circuit (or last. I haven't checked which side is hot yet). Before opening it up, I'd assumed the thermostat would be on a very low voltage part of the circuit, merely controlling a solenoid or something, but it turns out it's directly in the power circuit, and therefore I will need a 120v jumper and switch.
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I don't know if there is a way to adjust the stat, not that I saw. That would solve my problem real quick.

I am thinking of putting in an on/off push button or toggle that will short circuit the thermostat if I want to the fan to be on at any temperature.

(The fan runs off the work shed power bar, so it will only be on when I am in there with the power on.)You guys always seem to come up with solutions I hadn't thought of.
 
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I suggest using either a toggle switch or a slide switch, they tend to be a little more reliable than the commonly available alternate-action (latching) pushbuttons.

Cheers,
Tom
 
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FAQ: Window fan: Bypassing thermostat with a button

Why would I want to bypass the thermostat on my window fan?

Bypassing the thermostat on your window fan allows you to manually control the fan's operation regardless of the ambient temperature. This can be useful in situations where you need continuous airflow, such as for ventilation or to assist with cooling other appliances.

Is it safe to bypass the thermostat on a window fan?

Bypassing the thermostat can be safe if done correctly, but it involves modifying the electrical components of the fan, which could void the warranty or create a fire hazard if not done properly. It's important to have a good understanding of electrical systems and to follow safety precautions.

How do I bypass the thermostat with a button?

To bypass the thermostat with a button, you would need to connect a switch in parallel with the thermostat. This involves identifying the thermostat wires, cutting them, and then wiring a button or switch between the cut ends. When the switch is closed, it will create a direct circuit, bypassing the thermostat.

What tools and materials do I need to bypass the thermostat?

You will need a screwdriver, wire cutters, electrical tape, a button or switch, and possibly a soldering iron if you need to make secure connections. Additionally, a multimeter can be helpful for identifying the correct wires and ensuring a proper connection.

Will bypassing the thermostat affect the fan's performance or lifespan?

Bypassing the thermostat can lead to the fan running more frequently or continuously, which may increase wear and tear on the motor and other components, potentially reducing its lifespan. However, if the fan is designed for continuous operation, the impact may be minimal.

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