I give up.I made one big central control to heat 4 rooms on -15 outside. And i have to put Control on 80c-90c just to make those 4 rooms up to 21c. I cant leave it outside since its freezing and there is no point to heat up the room where control is since it wont cake in hot air. And intake fan is broken as well, you cant heat up the room if its connected since it will pull in cold air. And if its warm outside, there is no point for climate control. And temp jumps from -10c to 30c every sec. I tried to follow the instructions, but Control unit pick some random temp to heat up the air, like -8c even tho room is -12c and outside is -15c? How the hell it gets that temp?? Temp just goes up and down without logic. And Most of time it shows temp as NaNC? i dont underestand. And why do i need to have 2 separate systems if i just want to keep rooms on 21c? one for cooling on heatwave and one for heating on cold snap? For separate fridge units, its cool, but for plain base warm up, its confusing. I have 1 big Control so there is 1500% eff and 100% air flow but still no use.