ferm chiller thermostat

this is what i just brought home, i am pretty sure it will work, am i wrong?

it runs on 2 AA batteries

http://customer.honeywell.com/Techlit/pdf/69-0000s/69-1799.pdf

Just looked at the .pdf and it says the setpoint range is only 59-95F so im not sure if it will fit your needs, but hey anythings worth a shot atleast once.

damn , missed that, but i will prob be setting it to around 62 anyways

ehhh i found this:

Note: Do NOT use "programmable" or "digital" thermostats, as they require the "normal" 24 VAC power supply to operate, rather
than the 12 VDC we're using. Stick to the simple, mechanical units described here.


on page 9 of this:
http://home.elp.rr.com/brewbeer/chiller/chiller.PDF

has anyone had any success with the digital type of thermostat being used to control a fan?

I haven't made one yet but was planning on hooking the thermostat up to a normal wall plug on the inside or outside of the chiller box and then plugging the fan transformer into that.

I use a digital one a lot like that. I think that comment about power only applies if you're talking about powering the thermostat from the wall as well... But I just run mine on two AA's. It's been on for about a year now without issue, so wall power seems unnecessary. I just use a 12VDC adapter switched through the thermostat's output relay to drive a small computer fan in my fermentation cabinet.

Funkenjaeger said:

I use a digital one a lot like that. I think that comment about power only applies if you're talking about powering the thermostat from the wall as well... But I just run mine on two AA's. It's been on for about a year now without issue, so wall power seems unnecessary. I just use a 12VDC adapter switched through the thermostat's output relay to drive a small computer fan in my fermentation cabinet.

Click to expand...

Which terminals did you use? I'm hooked up to both R terminal and the G, but it won't go.

hey MEW, i am wondering that same thing, I made a thread here:

https://www.homebrewtalk.com/showthread.php?t=69275

a few weeks ago but i guess no one has enough experience to help. I think I will go check the circuit board and follow the traces off of the relay and figure out which terminals they go to, but i am guessing its (G) and (RH jumpered to RC). today pretty much everything else is done on my unit and wiring is the next step, so i might just have to rifle through all the possible connects untill i get it to work.

jaegar any help would be great with this, if you see this, thanks

Make sure the thermostat is set the "Cool" setting. Your relay wires should go to the Rc and Y terminals. There is no power provided by the thermostat to activate your external relay, so you'll need to wire one in series to one of the legs. Make sure that the relay and voltage source do not draw more than 24W (the limit of the relay inside the thermostat that connects Rc to Y).

GNBrews said:

Make sure the thermostat is set the "Cool" setting. Your relay wires should go to the Rc and Y terminals. There is no power provided by the thermostat to activate your external relay, so you'll need to wire one in series to one of the legs. Make sure that the relay and voltage source do not draw more than 24W (the limit of the relay inside the thermostat that connects Rc to Y).

Click to expand...

I have an external power source, but are you saying I need an external relay?

GNBrews said:

Make sure the thermostat is set the "Cool" setting. Your relay wires should go to the Rc and Y terminals. There is no power provided by the thermostat to activate your external relay, so you'll need to wire one in series to one of the legs. Make sure that the relay and voltage source do not draw more than 24W (the limit of the relay inside the thermostat that connects Rc to Y).

Click to expand...

im not following ya... what goes where now?

How are you trying to hook up the freezer to it? By using the freezer cord? I think what the problem might be you are trying to hook it up directly like the johnson controller. (Which would fry it if it tried to come on.)In order to use this one according to the pdf you have to hook it up to the relays in the freezer. A relay is a switch that is turned on or off with low voltage(the thermostat) to control a higher voltage application (the freezer). You can not just plug the freezer cord into the thermostat. I have never looked inside a freezer to know for sure if they even use relays(it seems like they would). but trying to run the appliance voltage through the thermostat is a no-no on relay type switches. this info is limited in value due to the inexperience of the poster(me).

no freezer here, we are talking a 12 volt fan in the SOFC...

I know to put the thermostat in series with the fan , like a switch. I am just wondering if you hook up the 2 leads (wall power positive and Fan Positive) to (Rc and Y) or (Rc and G)

im lookin at this here, I think this is the way to do it without blowing up the fan or the therm. :

https://www.homebrewtalk.com/showthread.php?t=69275


but I dont know if instead of in the picture above hooking the fan + to the Y terminal on the thermostat, I should hook it up to the G terminal... any ideas?

stevecaaster said:

no freezer here, we are talking a 12 volt fan in the SOFC...

I know to put the thermostat in series with the fan , like a switch. I am just wondering if you hook up the 2 leads (wall power positive and Fan Positive) to (Rc and Y) or (Rc and G)

im lookin at this here, I think this is the way to do it without blowing up the fan or the therm. :

https://www.homebrewtalk.com/showthread.php?t=69275


but I dont know if instead of in the picture above hooking the fan + to the Y terminal on the thermostat, I should hook it up to the G terminal... any ideas?

Click to expand...

I'm pretty sure you'd hook it up to the g terminal. When I do that, I can get the fan to go in either the heat setting or the fan on setting, but not the cool setting. When connected to the y terminal, the fan never goes. In short, I think you'd use the g terminal, and I think my thermostat is broken.

mew, you do have Rh and Rc jumpered together right?

I just did something like this for my fermentation cabinet, check my sig.

1) Digital works fine, you just have to be creative. I originally wired mine using a PC power supply, but now just run it on batteries after drawing a bit too much current on a test run. Hook your fans to the cooling circuit (I used Y and Rc), and the thermostat should run on batteries.

2)there is a good website around that shows how to remove the thermistor and make it remote, if you check the links on my project, I am sure you will come across it.

3)The 24V ac circuit is if you are wanting to run it off the heating/cooling system power. the AA batteries should give you all the juice you need.

4) if wanting to hook it to a fridge thermostat, you will need a relay between your thermostat and the fridge thermostat. Again, I think I detailed this in my fermentation chiller project.

If you have questions, feel free to ask.

stevecaaster said:

mew, you do have Rh and Rc jumpered together right?

Click to expand...

Yeah, I do. Mine's just broken, I think. The cool setting never makes a clicking sound like the heat does.


Thanks for that info., death. It's very useful.