Sous Vide Cooker with Universal Controller

By Jake Spurlock
Category: Electronics, Food & Beverage
Time Required: 4-6 hours
Difficulty: Moderate

The sous vide (pronounced "soo-veed") technique involves cooking food in vacuum-sealed pouches submerged in a water bath held at a precisely-controlled temperature.

This guide will go through the steps necessary to build your own sous vide cooker. What is unique about this design is that the controller was built with more than just sous vide in mind. The controller is a general-purpose PID type controller but the external interfaces were partitioned so that other items can be controlled. The output of the PID controller runs through a high-power solid-state relay to a standard 120V outlet. A second 120V outlet is available for "continuous on" type of interfaces.

In the sous vide cooker the solid-state relay output switches a heating element on and off. The thermocouple input to the controller is through some banana jacks on the rear of the controller box.

Other features that make this controller unique are that an integrated power cord, fuse and lighted power switch are used, and all of this is mounted in an aluminum enclosure to give the project a professional look and feel.

Steps

Step #1:

A 3.5G Rubbermaid plastic food storage container was used. A hole was cut with a Dremel tool using a crosscut bit and cleaned up with a sanding drum. A water kettle heating element was then installed in this hole. The element was slightly offset to the side to make room for the water pump and thermocouple.
The silicone grommet that comes with the kettle heating element is somewhat difficult to install. Do not size the hole too large as the grommet will fit in a hole approximately 1" in diameter. I used the inside diameter of the grommet as a guide for the hole size.
Once the grommet is in place the two halves of the kettle heating elment go together. One advantage of using a kettle heating element is that the device has a high-temperature shutdown bimetalic switch built into it. If for some reason the water were to boil off the element would not be allowed to continue to heat and possibly melt the enclosure.

Conclusion

The controller is assembled as a standalone unit. One of the two 120V outlets is controlled via the PID controller and solid-state relay. The second 120V outlet is switched with power button and used in this case for a recirculation pump.

3 Responses to Sous Vide Cooker with Universal Controller

mike on March 26th, 2013 at 10:06 am said:

How do I callabrate the controller to the temp prob? My controller will read 150 but the true temp is 140

Reply ↓
Linongi on April 29th, 2013 at 4:43 am said:

Could you tell me if this pump is suitable high temperatures ?

thank you

Reply ↓
Linongi on April 29th, 2013 at 6:40 am said:

Maybe I misspoke. My question was if the Aquarium Pump what you use can withstand high cooking temperature

Reply ↓