Wiring two cooling fans to aSTC-1000

The Homebrew Forum

Help Support The Homebrew Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

private4587

Member
Joined
Sep 11, 2016
Messages
566
Reaction score
86
Location
Middlesbrough
I am about to embark on building a brew fridge, within it will have a 60w heater and two fans. I would like the fans to run on both the heat and cooling cycles but not when neither are running. Any ideas on how to wire these fans into the controller.
 
It can be done however it's not that straightforward, yeastinfection's solution is much easier.
If you do want it the way you suggest then you'd need a dpdt relay, connect the relay coil to the cool output live and neutral, break another live from the cool out through a NO contact to the fans, break a live from the heat out through a NC contact to the fans, connect a neutral to the fans. Sorry if that's not very clear, difficult to describe :?
 
I was thinking that i would need two fans for correct circulation of air within the fridge i.e. one at the top and one at the bottom. would one fan running at the bottom give me correct circulation?
 
Much easier to pick up a couple of 12v computer fans and an adapter and just leave them running 24/7. For a regular undercounter fridge sized space one would probable be enough.
 
bare in mind its a fridge /small unit small volume, not a warehouse,alot of us dont use a fan,and some that did,dont use one anymore, sounds like your over thinking things,
like the above post says, 12v adpator and pc fan, adpators are about £3 from ebay and pc fa fan is free or 99p,
if you want it off when no heat or cooling is operating then just double plug it from the output on the inkbird,
 
Seems to me there is a lack of understanding how fans cool things on here. A fan just moves air around, what causes cooling is the evaporation of water that the moving air causes. By putting a fan in a brew fridge you are just moving warm air around in the enclosed space in the fridge, unless there is some water in there to evaporate and thus cause a cooling effect. A pc fan works slightly differently, the pc produces a lot of heat so the fan moves air that is already cooler over the hot components. The heat transfers from the components to the cooler air and disperses it, a bit like a wort chiller transferring heat.

I always just assumed that when people make a brew fridge, the fridge is plugged into the cooling socket and comes on when cooling is required. The area in a fridge is so small anyway it is very unlikely there will be any benefit to move the air around with a fan.

I am planning on doing a brew fridge next year and have a heat belt. I was planning to have my STC100 external to the fridge with teh frisge plugged in for cooling and heat belt for heating. The temperature sensor and heat belt will be put through a cut out in the door seal which I will then reseal with blutac (low budget solution). I am aware there may be a plug in the back that can be removed but not sure its on all fridges and dont know exactly what to look for so looking at the easy route. As long as its properly sealed. Is there any reason this wont work?
 
Seems to me there is a lack of understanding how fans cool things on here. A fan just moves air around, what causes cooling is the evaporation of water that the moving air causes. By putting a fan in a brew fridge you are just moving warm air around in the enclosed space in the fridge, unless there is some water in there to evaporate and thus cause a cooling effect. A pc fan works slightly differently, the pc produces a lot of heat so the fan moves air that is already cooler over the hot components. The heat transfers from the components to the cooler air and disperses it, a bit like a wort chiller transferring heat.

I always just assumed that when people make a brew fridge, the fridge is plugged into the cooling socket and comes on when cooling is required. The area in a fridge is so small anyway it is very unlikely there will be any benefit to move the air around with a fan.

I am planning on doing a brew fridge next year and have a heat belt. I was planning to have my STC100 external to the fridge with teh frisge plugged in for cooling and heat belt for heating. The temperature sensor and heat belt will be put through a cut out in the door seal which I will then reseal with blutac (low budget solution). I am aware there may be a plug in the back that can be removed but not sure its on all fridges and dont know exactly what to look for so looking at the easy route. As long as its properly sealed. Is there any reason this wont work?
I think you might be misunderstanding what the fans are being used for. They're not there to cool anything but as you said just to move air about. If you have, for example, a greenhouse heater mounted underneath the shelf which supports your FV then it might pay to have something blowing the warm air out from under the shelf and helping to circulate it.

You can argue whether or not there's a need, but that's a different thing.
 
I think you might be misunderstanding what the fans are being used for. They're not there to cool anything but as you said just to move air about. If you have, for example, a greenhouse heater mounted underneath the shelf which supports your FV then it might pay to have something blowing the warm air out from under the shelf and helping to circulate it.

You can argue whether or not there's a need, but that's a different thing.

I think you may be right. Personally I would be happy to keep the heat under the FV with proper temperature control
 
Hi!
I don't have a fan in my brewfridge and I haven't had any problems fermenting decent (kit) beers. I have been considering fitting one, but I would certainly include a speed controller as computer fans rotate far too quickly - all you need is a gentle flow of air.
You could wire a trailing socket into the heating circuit of the STC1000 and plug a 12v adapter into that socket to power the fan.
 
Hi!
I don't have a fan in my brewfridge and I haven't had any problems fermenting decent (kit) beers. I have been considering fitting one, but I would certainly include a speed controller as computer fans rotate far too quickly - all you need is a gentle flow of air.
You could wire a trailing socket into the heating circuit of the STC1000 and plug a 12v adapter into that socket to power the fan.
I'm in the middle of building something similar and have gone for 40mm fans, they don't shift as much air as the regular 120mm ones do and are easier to fit into small spaces. Plus instead of a speed controller you can just use a lower voltage adapter, something like an old 6v phone charger might do.
 
In a brewfridge the medium of heat exchange is the enclosed air. So a fan which helps move the air over both the surface of the brew vessel and either the heat or cold radiators is a HUGE benefit to efficiency.

Buy a commercial fridge or top-top end domestic model and you will find a fan fitted as standard ;)

a single standard pc case fan powered with virtually any 5v+ dc powerbrick/phone charger will be ample to keep the air moving about just dont make the same mistake i did and epoxy the fan to the inner shell of the fridge DOH!! ;) After a couple of years of 24/7 use the fan i had used (pulled from an old pc case) finally died requiering me to gut it and use its frame as a mount for its replacement.
So while they work a treat and are cheap they may only last a few years of use so think exchangeable when fitting ;)

edit fwiw the worst thing for brewfridge efficiency is opening the thing to check on the brew as all the optimum temp air will drop straight out when you open the door. Glass fronted fridges (ex bottle fridges ) are good on that front ;) since mini video cameras, web cams, ip cams, endo cams etc are so cheap n prevalent these days i wonder why more folk dont fit them to monitor the insides of their brewfridges,
Me - i went with a glass doored bottle fridge with an external light switch ;)
 
Me - i went with a glass doored bottle fridge with an external light switch
Hi!
My local working men's club had two glass-fronted bottle fridges that failed the PAT test, so new ones were installed. The old ones "fell" into my mancave and work perfectly. The double fridge houses two cornies, and the single is destined to hold a third.
They will suffice until I get a dedicated keezer (negotiations with SWMBO on this development are at an impasse; further talks are scheduled for the new year).
 
since mini video cameras, web cams, ip cams, endo cams etc are so cheap n prevalent these days i wonder why more folk dont fit them to monitor the insides of their brewfridges,

I've got one and you're dead right, I'm brewing in the garage for the first time and my IP cam has saved me having to go out into the cold regularly to check up on things. Highly recommended.

uc
 

Latest posts

Back
Top