Fermentation Chamber Controller Build

[Grande69]

I am trying to build mine around the STC-1000. I understand how to wire the receptacle for controlling the heating and cooling source. I want to go one step further and have a third receptacle to power a recirculation fan. I only want this fan to come on when either the heating or cooling cycle is powered. How would I do that?

Tony

[SamIam]

Are you still planning on using a A/C unit for the cooling? If so, why do you want to wire in a separate fan for cooling? The A/C unit has a fan. For the hot side, here is one way you could do it. Mount two outlets in a double gang box. Wire common (white wire) to the left side of each outlet. On one of the outlets cut the tab on the hot side (right side when facing the plug) between the upper and lower plugs. Wire the STC-1000 power for heat to the top plug and the power for cool to the bottom plug. Then just jump the hot side of the top plug to the other outlets hot side.

[Grande69]

I was thinking of using a recirc fan in both modes. The chamber I'm planning will be taller than it is wide, and wanted the temperature to be consistent between the upper and lower portions. I also plan on putting a paint can light bulb type apparatus inline with the recirc tubing, so when/if it needs to be heated, there won't be anything inside the chamber taking up space.

[SamIam]

Well, if you wanted to just use one fan why not just let run run all the time, at least while your fermenting? If you want to cycle the fan when it heats or cools you'll probably have to use two fans, one for heat and one for cool. There might be a way but I'm not sure how you could do it with just one fan and not power the opposing stage.

Also, keep in mind that there are very few days I have to heat my chamber. Even in winter when the garage is 55 deg, the fermentation will generate enough heat to where the thermowell/probe will cycle the A/C. It's only a few days after fermentations has begun that I would need to provide heat, if at all, and by that time I don't need to cool anymore.

[dhempy]

There might be a way but I'm not sure how you could do it with just one fan and not power the opposing stage.

Relays are one option. You wire it so that the controller energizes the relay which in turn energizes the fan. Radio Shack carries these ... but you can find others too ... the key is to get the correct trigger voltage .. I am assuming that your controller outputs 120v ... if it outputs something else like 5v or 12v as the "signal" then you need to find a relay that uses 5v or 12v as the "signal" and switches 120v. You can see inside the Radio Shack version to see how it works .. there are Solid State Relays (SSR)s as well .. but the Radio shack relays work well .. I had a pair of them in my old brewery controlling pumps.

Dan

[bwarbiany]

I only want this fan to come on when either the heating or cooling cycle is powered.

Why? I use 3 standard PC case fans in my keezer to maintain equal temps throughout. A quick search online suggests that one PC case fan uses somewhere in the range of 2W (probably lower). That equates to about 1.5 KWH per fan per month. For 3 fans, I'm therefore using (high estimate) 4.5 KWH per month.

A look online suggests that average energy prices in the LA area are $0.193/KWH. So these fans cost me less than a dollar a month. And that's a high estimate, and that's for 3 fans, which is probably overkill.

So what's the reasoning to only have this fan on during heating/cooling?

[DrDually]

Seems to me that after purchasing all items needed, it would cost more than simply buying a used fridge from Craigslist for $40-50
When not using fridge for fermenting, I keep kegs and bottles chilled
Just my .02 worth

edit: Here is a free one http://orangecounty.craigslist.org/ele/3176216957.html

[dhempy]

Seems to me that after purchasing all items needed, it would cost more than simply buying a used fridge from Craigslist for $40-50
When not using fridge for fermenting, I keep kegs and bottles chilled
Just my .02 worth

Sometimes the drive to "tinker" outweighs the practical. I am certainly guilty of putting tinkering ahead of practicality ... and there are others too ... eh Derrin?

Dan

[Grande69]

Hey Chris,
The free fridge certainly would fit well in my plans, but I am not too sure I could transport it safely in my Mustang convertible!

[DrDually]

Seems to me that after purchasing all items needed, it would cost more than simply buying a used fridge from Craigslist for $40-50
When not using fridge for fermenting, I keep kegs and bottles chilled
Just my .02 worth

Sometimes the drive to "tinker" outweighs the practical. I am certainly guilty of putting tinkering ahead of practicality ... and there are others too ... eh Derrin?

Dan

Hi Dan
I agree with the "tinkering" aspect and do a great deal of it myself being a fabriactor etc. I also like to share things I have found that that work and things which do not work, or do not work well, and will share with others.
Ultimately it is what the brewer wants to do in regards to abilities and cash resources
That being said, lets have a beer

[nevery]

Sometimes the drive to "tinker" outweighs the practical. I am certainly guilty of putting tinkering ahead of practicality ... and there are others too ...

X2!! Lol.