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Topic: Controlling an Split-air-conditioner Indoor-unit with Arduino. I'm lost. (Read 44 times) previous topic - next topic



The 0th thing: I'm Hungarian, who learned English from only the Internet and specifically YouTube. I'm trying my best, but if I'm not clear somewhere, ask.

I will first briefly explain the project I'm doing, just so you can understand the background of my problem better. tl;dr: It's complicated, and understanding it is not necessary to answer my core question. You can skip it.

I'm building a homemade air conditioning and garden watering system. It uses the cold well-water from our drilled well (I'm not sure, how it's called in English, in Hungarian it's a "fúrt kút". Basically, a tube is drilled down into the ground, to ~80 m (~262 feet).
It brings the aquifer water (the ground water below a layer of clay) up from there.). The water that comes from the well is no matter the weather 14°C (57.2°F). We'd use the water to water our garden anyway, so why not chill the house as a fortunate side-effect?
I use a used air conditioner indoor unit to extract the coldness of the water.
Everything is controlled with two Arduino, one Mega controls all the solenoid valves, pumps, and everything, and is outside in the garage. And one Uno is inside the house and acts as a thermostat, and controls the indoor unit. How strongly to blow, when to circulate the water, according to the temperature. The two Ardus are communicating on Serial (I'm using the EasyTransfer library, but that's irrelevant).

The problem:
I want to control the indoor unit with an Arduino Uno. The things that I want to control:
- The stepper motor of the... This thing: (I have no idea how it's called)

It would be nice to be able to move the blades up and down controlled. However, the motor is a stepper motor, for wich, many tutorials exist, so I'm not in need of help here. Here are the pictures from the blade moving stepper anyway:

- The fan motor of the indoor unit. And this is the bigger challenge, and also the more important one. Here are some pictures.
The motor is powered by PWM, at 230V-s. I've dug around for an hour, and have still no idea how it should be wired up. But I've gathered some information: There is a speed sensor built in, I have no need for that, I will experiment out the speeds, and that's it, no need for active control. The motor is an asynchronous motor.
I would like to have around 3 speeds that I can control with the Arduino. Unfortunately, it's not as simple as building a 230V PWM.

This is the motor:

More pictures

Spec sheet of indoor unit:

Sorry for the not really well-put-together post, I'm really lost here.

Huge thanks for any help!

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