I’ve got a question and I think this is the best place to put it since growers deal with heat pumps often…Please move if you feel there’s a better spot.
The situation is that I had a samsung mini split (Model# AC036MNTDCH) installed in a product room with a desired temp of 55F. Despite discussing with the installers the target ambient temp, they overlooked the fact that the mini split has a lower set limit of 65F. The unit should be able to drop the room to 55F as it is more powerful than the AC unit that had been doing the job before. The installers have not been able to fix it. Frankly, I think its one of those things where, if they knew how to fix it, they would. And, they don’t want to just rip it out and put something else in. I’m also going to reach out to Samsung personally.
So, I’m checking in to see if somebody has a solution to this before we play hardball with the installers.
When making “chillers” out of AC units, the low tech version is to place the sensor in a glass of warm water…the “high tech” version is to use one of these
You need to grab an RS485 controller. Agrowtek makes and affordable “turn key” option.
Once you have real control over a heat pump, and dehumidifier with reheat it’s game over. Getting everything centralized on a SINGLE controller like GrowLink is the best idea but can get expensive. You can get a basic grow link setup with 2 channels of digital or analog for like $5k.
It also takes a little time to build logic to get your rooms super dialed in.
Also if this is for just like a hash room, you could try something like a coolbot hack
Though @SubstituteCreature or @cyclopath could walk you through an alternative to Coolbot that will probably cost less than $50 if you’re into DIY and on a budget
It depends on what kind of unit they’re using, but with residential wall style ACs (and some floor models) the temperature control sensor is like right on the grille of the condenser coil - those are usually 2 wires coming off of it as it’s just a certain type of resistor, I extended those to the ass end of the AC where it exhausts so it always thinks it’s hot well past the rooms 60f limit on the AC itself.
if you’re worried about getting it TOO cold you can always set up a temperature shutoff switch via one of those grow controllers that you can program to turn things on/off at a certain degree that way if it goes below a certain level it’ll shut the AC off FOR you but the issue with that is that if it’s a digitally controlled AC you may have to manually turn it on but at that point you could just damn near jump the entire control panel so when it gets power it’ll turn back on. All and all that’ll cost you less than 50 bucks with the majority of the cost being the shutoff box if you’re trying to get a killswitch running on it
It should be said that @vortal illuminated a WHOLE lot in this area for me, too.
After a bit of a google for your model number if you want to accomplish this…this is where to look.
As per the manual for that model range.
Just follow your temp control sensor to it’s endpoint and look at the wiring to determine if you can play slicey dicey with it and not fucking your AC up, on most it’s a pretty easy splice job
There are 2 sensors (or more) in mini split systems. The “ambient or room” sensor and then the “coil or tube” sensor(s)
The coil sensor will likely be in a little housing attached to the tube themselves and the ambient sensor will be mounted on the fins.
If you hang the ambient sensor in front of the exhaust you suggest, @vortal and @SubstituteCreature that the compressor will constantly stay “on” blowing cold air bc it believes the room to be as hot as the exhaust air?
To override the low temp setting on a mini split system, you can typically adjust the settings by accessing the system’s control panel or using the remote control. Look for advanced options or a hidden service menu where you can modify temperature thresholds. Depending on the model, there may be a setting to override the low temperature lock or increase the minimum set temperature. For specific instructions, refer to the system’s manual, or consult an HVAC professional for assistance with adjusting the “Override low Temp Setting Mini Split.”
