I bought this after my greenhouse thermometer failed and shut the gas heater down during a week of 5-10F degree days. I was able to reset the thermometer to power up the gas heater but lost a lot of plant material. I have been running this at a pretty low setting and along with the gas heater I have been able to maintain an overnight temp of 50F. Only gave it 4 stars because I have only been using it for 2 weeks.

This little heater is a plant saver. We used it on nights when temperatures were in the middle 30's. It has two settings 1300 and 1500. We put it on 1300 and barely had it cut on. It kept it toasty in the greenhouse and I just got our electric bill and it didn't add anything at all.

I have three of these in the greenhouse. it is 10' X 14' and these little guys keep it nice and warm. I have the optional remote thermostats with all three, so it gets a little pricey, but they keep the temps at 68F where I have them set at unless it gets down in the 20's, and then it maintains 65F until the sun comes up. They are very quiet and easy to move around. I am growing peppers, lemon plants, and all of my wife's flowers and spice plants.

I’ve tried others but they were too much this is perfect for my small greenhouse

My plants are thriving

I bought this heater to keep the temperature in my small (6'x8') uninsulated greenhouse above freezing this winter. On the lowest setting it kept the temperature at 50 degrees when the outside temperature was in the 30s and at 40 degrees during a cold snap where the temperature stayed in the low to mid 20s. Haven't got the electric bill yet so I can't say how efficient this unit is, but the plants offered to chip in to cover any increased cost.