Electric Heaters Thermostat Calibration Technique
The electric heaters supplied by BC Greenhouse Builders come with built in thermostats. These built in thermostats are not precision instruments but rather offer a ‘cool to hot’ temperature range. In order to set these thermostats to your desired temperature you will need a maximum-minimum thermometer and a few colder nights.
To calibrate, at night you set the built in thermostat to a setting in the range you believe will be close to the temperature you want, knowing the range is cool (30f to 50f) to hot (70f to 80f). In the morning you inspect the maximum-minimum thermometer to see what the coolest temperature the inside of the greenhouse was overnight. From this reading you can fine tune your heater thermostat setting up or down to get closer to what your desired temperature is. You repeat this step over the course of a few cold nights until the built in thermostat is maintaining the desired overnight temperature in the greenhouse.
Some things to consider with this process is that after you have your thermostat set to your desired night time temperature, moving the heater or adding or changing air circulating fans will alter the temperature reading at the maximum-minimum thermometer location so you may need to recalibrate your thermostat.
Finally, if a specific precise temperature is desired we would suggest adding an external greenhouse thermostat which would be hardwired into the power cord of the heater or the power supply for the heater. These are precision instruments and which can be set to an exact temperature right off the start. You should keep in mind that you may still want to use your maximum-minimum thermostat at different locations or heights in the greenhouse as there will always be different temperature zones in the greenhouse depending on factors like heater location and air circulation.