How do you get to your ac sensor to bypass shutoff temp?

[Matteo57]

I am building a cool box and my 5k BTU ac unit keeps shutting off and going back to the fan every minute or two. It won't cool past low 60s. How do I get to the sensor? I was thinking of trying to pull the sensor out of the cool area and have it outside and it should be fine.
I have googled it for a bit and can't find anything showing how to get to the sensor and what it looks like?
I just got the cheap one from Home depot (link below). Any help would be awesome! Thanks!

http://www.homedepot.com/p/LG-Electronics-5-000-BTU-Window-Air-Conditioner-LW5012/203127491

 

[number40fan]

Most sensors are right in front of the evaporator, which is right behind the grill area of your unit. If you pulled the filter up and out, I bet you would see it. Then, more than likely, remove a few screws around the outer portion of the front area and you will be able to move the sensor.

 

[Matteo57]

Cool, I think I got it. Thanks a bunch!

 

[Matteo57]

It now is going under the 63F it was stuck at before but now it's stuck at 59.... The fan is still cycling on quite often.... The temp probe looks like it is on the tip of the wire, but is it the whole thing? Is there something I'm missing? Why is the fan still cycling on so much?

 

[FourSeasonAngler]

Get a small cup of water or better yet a small resealable container of ice-pack gel and insert the temp probe into it. The water or gel will insulate the probe so that the A/C will stay on long enough to cool that gel or water to your desired temp.

 

[number40fan]

I'd find a way to get that sensor out of the box.

 

[number40fan]

Oops, sorry, it does look like it is poked through the wall. Hard to tell from the picture, but how far does that clear tubing run down it? As in how much is left exposed before it pokes through the wall.

 

[Matteo57]

Oops, sorry, it does look like it is poked through the wall. Hard to tell from the picture, but how far does that clear tubing run down it? As in how much is left exposed before it pokes through the wall.

Maybe an inch or inch and a half. Should I put some sort of tubing or something around it for that bit it's exposed?


FourSeasonAngler: Get a small cup of water or better yet a small resealable container of ice-pack gel and insert the temp probe into it. The water or gel will insulate the probe so that the A/C will stay on long enough to cool that gel or water to your desired temp.

I'm confused as to what this would do. Doesn't the ac unit shut off and cycle to the fan when it gets too cold? Don't you want it to get hot and not cold?

 

[number40fan]

Try to wrap something around all of the line from the wall to the A/C unit. See how she does then.

What temp are you trying to get down to?

 

[day_trippr]

If that really is a bulb and capillary tube style sensor, be careful not to breach or crimp that thin tube, unless you want to take on a real modification to the control circuit.

That said, totally bypassing the thermostat and using an add-on/external controller might be what's needed here anyway...

Cheers!

 

[whoaru99]

It can only drop the ambient air temp so much...

If you get it set up just right you may succeed in freezing up the evaporator.

 

[day_trippr]

Considering the volume being cooled, if the chamber is reasonably tight the odds of icing up the evaporator become very small.

A few days ago someone posted how he had a controller malfunction and his AC unit brought his chamber within a few degrees of freezing. Very impressive, and indicative of what can be accomplished in a small tight space...

Cheers!

 

[Matteo57]

Try to wrap something around all of the line from the wall to the A/C unit. See how she does then.

What temp are you trying to get down to?

I'll try this and see what happens.
I would like to just get it mid 50s. It is probably around 95-100 in my garage so I guess 60 isn't horrible, but I was hoping for just a bit more.
it is really insulated fairly well and sealed up tight. I don't think I'm losing much there. I am pretty sure its just not dropping much more due to cycling back and forth to fan too much.
I'll see what wrapping something around the copper pipe does.
Thanks!

 

[number40fan]

I bet that wrapping the sensor will get you where you need to be. Put a little dab of caulk where it pokes through the wall too.

 

[Matteo57]

I bet that wrapping the sensor will get you where you need to be. Put a little dab of caulk where it pokes through the wall too.

any suggestions on what you would wrap it with?
I was planning on caulking it when I figured out if it would fix the problem or not first.

 

[number40fan]

Try something simple like a hand towel.

 

[Matteo57]

Try something simple like a hand towel.

This definitely helped! For a permanent solution, should I just caulk around the length of the exposed wire?

 

[number40fan]

No, I don't think the caulk would be sufficient enough as a insulator.

 

[Orthobrewsky]

If you don't mind pulling it out so that you can remove the cover, there should be an neater way. I don't have the same model, but it has similar controls. Here's how it goes:

Pull on the knob to take it off. Then unscrew what you need to to take off that cover and get to the thermostat (the knob was connected to the thermostat). The thermostat should be plugged into two metal tabs or otherwise be connected at two terminals. Remove the thermostat (mine just unplugged) and your sensor should come out with it. Short circuit the leads which were connected to the thermostat. This should keep it on whenever it is plugged in.

If you would rather keep it more like it is, you could tie a little Christmas light bulb or night light to the sensor so that it always stays warm no matter the outside temp.

 

[Orthobrewsky]

Of course, you would want to unplug the unit before removing the cover.

 

[Matteo57]

I bet that wrapping the sensor will get you where you need to be. Put a little dab of caulk where it pokes through the wall too.

So, this worked but it only works for the first time you put the towel around it. After it hits the temp you want and it shuts off, the next time it turns back on to get to set temp on temperature controller it doesn't get nearly as down. The towel or anything I have set around the probe cools down to the room temp and thus making it useless again.
I think I am going to have to put a small low wattage light bulb into a can with the probe inside and set that to turn on every time the ac kicks in so it should keep it warm enough to keep the ac going no matter what.
Thoughts?

 

[number40fan]

Hmm. One more thing that I might try is placing a piece of hose all the way over the sensor, tape it up on the inside and run the hose through the hole to the outside air.

 

[Will Smith01]

Is a new 24000btu window unit suppose to cut off and on every three minutes when in heat mode? It can't be right and for $800 it should heat the room better but can't if short cycling. It's a wifi LG . Thoughts?

 

[day_trippr]

Welcome to the forums at Homebrew Talk, @Will Smith01 ()

Woof! That's a big mama window unit!

Can you provide a bit of context - like, what is the volume of the space this beast is trying to control?
I have all kinds of coolers and heaters including through-the-wall units (including a 29Kbtu machine which would approximate a big ass window unit) and none of them cycle anywhere near that short...

Cheers!

 

[whoaru99]

Is a new 24000btu window unit suppose to cut off and on every three minutes when in heat mode? It can't be right and for $800 it should heat the room better but can't if short cycling. It's a wifi LG . Thoughts?

Is it sized appropriately for the room?

Reason I ask is with AC and with heat, bigger is better isn't necessarily true and can cause short cycling.

 

[dmaxweb]

I have a dedicated walk-in insulated fermentation closet in my basement. I use 2 ink bird controllers. My 5,000 btu window AC control is electronic so it does not automatically turn on when power is restored so I needed to get creative I moved the A/C temp probe and taped it to the side of the AC. I also taped an incandescent nightlight near the probe.

The Inkbird 1 probe is in a thermo well centered in the fermenter. When the wort temp is above the set temp, it turns on the night light which tricks the AC to begin cooling. The problem comes if the AC ices up trying to get to the low Inkbird 1 set temperature. Inkbird 2 takes care of that. The probe is placed in the AC coil. The set temp is above freezing (I use 38F). At 38F, Inkbird 1 turns off the power to Inkbird 1. This turns off the night light which in short order tells the AC that set temp has been achieved. The compressor shuts off while the fan continues to run and warms the coils with room temp air. The AC has built in short cycle prevention which can be extended with Inkbird 2 setting if needed when the coil temp rises above 38F. At that point, Inkbird 2 turns on Inkbird 1 and the cycle repeats. You'll have to play around with Inkbird and AC temp settings and the distance between the AC probe to balance the process. I also use a small space heater if needed to raise the wort temp toward the end of fermentation (Inkbird 2 is not used). The heater wattage should not exceed the inkbird rating. Most small space heaters have a somewhat accurate thermostat. But, it should be set to somewhere near the Inkbird setting as a fail safe. On the cooling process this is not an issue since the controlled device is only a 7 watt light bulb.

I use the closet to store grain and other brewing gear which provides thermal mass so temp fluctuations are gradual when measuring wort temp. I use a small fan to constantly circulate the air

There is a point where this set up becomes impractical for a walk in closet. If you are doing lagers you'll likely need a real refrigerator with external temp control with the probe in a thermowell in the fermenter.
Too complex? A Coolbot will do the same thing but it will cost you $375. Inkbirds are regularly on sale on Amazon around $20.