The Principle of Thermostat Controller on Greenhouse

This article will explain how does the thermostat work in AUTO mode, and solutions for the troubles you might meet.

The main function of the thermostat is keeping the temperature in the greenhouse is even, it’s a priority program, the curtain will be partially closed, automatically up and down when Open TEMP > the current air TEMP > Close TEMP, and keep the air temperature is at the middle value between Open Temp and Close Temp you set.  

• How Does The AUTO Mode Works?

1. When (Open – Close TEMP>4°C) the Open TEMP is 4 degree celsius much greater than Close TEMP

The whole width of the greenhouse vent will be divided into some work areas, which are separated by temperature, every 2°C will be classed as a unit of work area. For example, the Open Temp is 30°C, the Close Temp is 20°C, there will be 5 work areas [ (30c-20c)/2c=5 ]. The controller will make the roll up guide pipe move for a specific time for every work area/every 2°C, the specific time depends on the LIMIT SET (total work time limit of motor, program SET 7, the default value is 1500 sec). If it’s on default value, the specific time for every 2°C is 300 sec (1500 sec / 5 work areas = 300 sec)  , check below picture and see the areas.

A trouble occurs.

In the same Open&Close temperature setting, while the air temp is just 25°C, some find their motor just closed completely. The reason is the time the motor uses, for the whole width of the greenhouse vent is much less than the default LIMIT SET 1500 sec, so please follow the below additional setting to make it work perfectly.

1. in manual mode, move the motors to the bottom, and long press 5 sec the CLOSE button, to zero the position of the motor. ( you can press DISP button, to check the middle screen, whether it’s 0000)
2. in manual mode, move the motors to the top, and long press 5 sec the OPEN button, to set the current position as max height. and if you can add 20 sec on LIMIT SET ( SET 7),  it will make the controller work better.
3. go to AUTO mode, test and make sure it works perfectly.

2. When (Open – Close TEMP=4°C) the Open TEMP is just 4 degree celsius greater than Close TEMP

For example, Open TEMP is 24°C and Close TEMP is 20°C, firstly, the curtain will only open once the air temperature reaches 24°C, the motor will stop as if the air temperature is less than 24°C, the motor will continue rolling up once it reaches 24°C again, back and forth until the curtain is completely opened. At this point, the curtain will keep open unless the temperature backs to the middle value 22°C, the curtain will be closed to half of the greenhouse vent. So on.

3. When (Open – Close TEMP<4°C) the Open TEMP is no greater than Close TEMP by 4 degree celsius

The curtain opens when it reaches Open TEMP, and the curtain closes when it reaches Close TEMP

Please email us if you have any question or concern. uygalaxy@rollupmotor.com