Hello Forum,
I'm stoked I found this site as I have a what I think is a relevant question and need help!
I'm aspiring to build an affordable and simple electric brewing system. Automation is not a goal. I don't mind adusting dials and turning off switches by hand.
I'm trying to figure out how to control my high wattage water heater element. I'll probably go with a 4500-5500W element and get a 240V outlet and breaker installed for my boiler and hot water tank. I'll also have a lower wattage element at some point as well running on a 120V outlet.
I want to be able to adjust the intensity of the element. I think that means changing the voltage running to them? I'm not electrically gifted, and that's why I'm coming here. When I close my eyes and envision the build I see myself turning a dial to adjust the output of my element. Is this possible? If it is, is it cost effective?

 

Use a thermostat which will turn the heating element off at a set temp, and on at a lower temp. Simple, cheap, and can easily find a food-grade thermostat.

Or, if you can't handle small swings in temp, you can use a triac (Dimmer switch) controlled by a microcontroller in a PID arrangement. Not as difficult as it sounds, but probably not necessary.

Edit: You can get 120v off of a 240v outlet to run your electronics, negating the need for a separate power cable. The electrician can explain how.

 

Does your hot water tank/boiler have a thermostat built in,dont know what country your in, you can use a separate thermostat like this for heating control, to lower the voltage on the heater use a simple light dimmer circuit, can you post pictures of what you have?

 

Have you looked at copper tank and immersion heaters, they would most likely be the most efficient, you could also put two 2.5 or 3k at 240v and switch them over to series for lower temp or maintaining temp.
They have built in thermostats.
If you want extra control at maintaining, you could also put third thermostat to switch over after the tank had heated.
Max.

 

Thanks for all the ideas and suggestions. I'm going to start looking into them and see how they work for my application. My worry with using the aquarium thermostat is that it can't handle the Amps? Is that a valid concern. I've read elsewhere it is, but that was on a beer website. Thanks again for all the responses!

 

There is thermostats specifically for immersion heaters that can be installed separately.
Max.

 

Most of the homebrew setups I have seen use a zero crossing solid state relay to switch the heater element. They are controlled with a cheap PID temperature controller bought on EBAY.

 

I used to home brew. I am a controls tech. Never got around to making my own microbrewery, but I have all the necessary parts minus vessel. I have several (all used, but working) Eurotherm temp 808 controllers, SSRs, and a 5kw 3phase immersion heater element (i believe configurable for single phase not sure, must check) in stock. I can sell to you way below market price. Pm if interested.

Edit: and thermocouples. Everything you need to get started, and for the price of single temp controller. And I can tell you how to set it up.