A Peltier device is a thermoelectric device which responds to a high current potential and converts the power into subsequent hot and cool surfaces.
These hot and cool surfaces are the surfaces existing over the flip sides of the device itself.
The principle is actually the reverse of “Seebeck” effect, according to which a potential difference can be generated across the terminals the opposite end s of two dissimilar metals when the other end which is joined is heated.
How to make a Peltier water cooler. Refer the DIAGRAM for better understanding.
The Peltier device exactly reverses the above process and though italso utilizes an integration of two dissimilar metals, it associates external voltage for operating so that it can produce the required cooling and heating effects across its two flat surfaces.
Once a Peltier device is connected to a voltage source having the specified current levels, it instantly starts the above transformations across its surfaces.
The hot side starts accumulating heat very quickly while the other end also show similar tendency but through opposite way i.e by cooling. However the hot side must be inhibited from becoming too hot, which if not controlled can lead to complete malfunction and damage to the device.
Once the hot is controlled the cold end can be simply used for cooling water or any other related purpose.