Bypassing the Temp Probe on a Window AC

Williams 728
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ardyexfor

ardyexfor

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Hoping someone can help me with bypassing thermostat so the AC unit won't shut off. I don't plan on lagering but I use a thermowell on my beers to control temperature of the liquid rather than ambient. So I could see this thing shutting off at ambient 60/65 being a bad thing. Hopefully the pictures I have posted will help.
 
In fact, if it is possible to wire in a second electrical cord for the compressor so that I can plug that into my temp controller and plug the factory AC unit direct to a wall outlet that would be preferable. Then I could leave the fan on at all times and let the Ranco tell the unit when to push cold air or not.
 
Looking at the wiring diagram, I believe there's a problem adding a second AC power source, in that the fan that cools the condenser is only going to respond to the controller.

It'd be a lot easier (and low risk) to simply connect the two sides of the thermostat to the "Cold Side" relay on a controller and let the controller mimic the thermostat function (set the AC thermostat as high as it'll go)...

Cheers!

[edit] If that's literally a five-position switch that can be set to run the fan - only - all the time, I suppose you could wire in a second pigtail with the black (hot) wire (on its brass contact) connected to the "COMP" C node, the white (neutral) wire (on its silver contact) to the wire labeled "BLUE OR WHITE (N)", and the green (safety ground) wire to the chassis or the wire labeled "G/Y OR GREEN". Then plug the added pigtail into a controller and you should be good to go.

But...that's a lot of work compared to simply bypassing the thermostat...
 
My thought in doing that was to keep the fan running all the time to help avoid the coils freezing. Rather than having the fan only come on when the unit begins cooling.

In any case reading that diagram is like reading another language to me. All I know is the wires coming from the compressor are red, blue and black.
 
day_trippr said:
Looking at the wiring diagram, I believe there's a problem adding a second AC power source, in that the fan that cools the condenser is only going to respond to the controller.

It'd be a lot easier (and low risk) to simply connect the two sides of the thermostat to the "Cold Side" relay on a controller and let the controller mimic the thermostat function (set the AC thermostat as high as it'll go)...

Cheers!

[edit] If that's literally a five-position switch that can be set to run the fan - only - all the time, I suppose you could wire in a second pigtail with the black (hot) wire (on its brass contact) connected to the "COMP" C node, the white (neutral) wire (on its silver contact) to the wire labeled "BLUE OR WHITE (N)", and the green (safety ground) wire to the chassis or the wire labeled "G/Y OR GREEN". Then plug the added pigtail into a controller and you should be good to go.

But...that's a lot of work compared to simply bypassing the thermostat...
Click to expand...

So if I'm understanding correctly. I would take a pigtail, wire its black wire, and wirenut that directly to the red wire coming from the Compressor. Take the white wire, and splice that directly into the neutral wire coming from the AC unit factory power cord. Then ground the green wire with the other wires at the ground screw. Plug that pigtail into my temp controller and the AC unit direct to a wall socket and away we go?
 
Yup, it's that simple, as long as you can set that fan to run all the time (I don't see an easy way around that while preserving the original wiring)...

Cheers!

[edit] Another alternative: you could just plug the original AC line cord into your controller, set that five-position switch to max cool/max fan, and stick a jumper wire across the two terminals of the thermostat. If you want to return the unit to actual AC service, just remove that jumper wire...
 
So then if the red wire is the hot wire for the compressor what do the black and blue wires do since they are still wired into the unit?
 
They do what they always did - the blue is a neutral circuit and the black is for the start capacitor. btw, you still have to plug the original AC line cord in, of course, otherwise that scheme won't work.

I think given the options, jumpering the thermostat makes the most sense...

Cheers!
 
Jumpering the thermostat? Do you mean just connecting the two red lines off of the tstat instead of wiring a pigtail and plugging the whole thing into the controller instead?
 
Yes, red to red.

Looking at the t-stat wiring, the easiest way to go is to just pop the two red wire female spade terminations off the thermostat and stick them together.

You can get male spade terminations of the same size and crimp a pair together as a jumper wire and use that, or if you're lucky find a piece of metal that has a male spade formed on each end (there's a name for that but it escapes me).

It makes everything much simpler going that route...

Cheers!
 
I realized its a wired Johnson A419 I currently have. But I will soon be replacing it with one of these: http://www.etcsupply.com/ranco-etc211000000-stage-prewired-temperature-controller-p-110.html

I plan to use the heat side with a mini space heater. What do you think would be the better route so I can make the transfer from one controller unit to the other without having to take apart the ac unit again in a few months.

If I should wire some extension wires from the two red wires out of the unit to wire each controller directly, how do I wire them into the Johnson controller I currently have. I looked at the manual that came with the unit and couldn't find this info.
 
Yes, you can swap them, no problem.

Do not under-gauge the wires you add to lengthen the red leads.
Those wires are carrying the compressor load.
Use at least the same gauge wire or better yet go up one gauge...

Cheers!
 
I'm looking to do something similar to this soon but using the Inkbird Temp Controller.

On (almost) all window units, I should be able to clip the (2) wires connected to the thermostat and connect them together and the unit will stay on all the time, correct? Putting total control in the external controller.

You start talking about cooler relays and I get lost.

thx
 

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