VIVOSUNPortable Greenhouse Heater with Adjustable Thermostat, 1500W/750W Electric Heater, 3 Modes for Fast Heating, Overheat Protection, Dustproof Design for Grow Tents, Patios & Outdoors

I bought the unit last. January used it once or twice and then put it away until two weeks ago. I pulled it out again for my new greenhouse which finally was full of plants and it worked like a champ. The thermostat was accurate and it kept things good. I went out to check it last week and it wasn’t working. I looked and somehow it overheated and started to melt a little where the heater cord plugged into the thermostat. Thankfully, the safety feature worked perfectly and shut down.I was very concerned, whether they would honor the warranty or even communicate to replace the product.The company has been fantastic. A little trouble getting through on the phone (I think it was a time zone issue) but when I did, they filed a warranty claim for me and followed up through email. Very responsive and they are shipping me an entire new unit. Have no fear if something happens with your unit, their customer service is some of the best I’ve come across. I will probably be buying a second unit for my other greenhouse when I start putting plants in it. My greenhouse is 4 x 8 x 7 if anyone is curious. Keeps it exactly the temperature I want.

I have purchased this product and it actually works really well. There's one problem though. The thermostat stops working after about a week. I have tried contacting the company and they have not responded to my emails. Luckily Amazon save the Day and is sending me a replacement. I'm only going to turn it on 750 watts and not 1500 w because I think that's what's blowing out the thermostat as the thermostat is not rated for 1500 watts. That's kind of ridiculous because it comes with the heater. As far as the heat output and it's ease of use it's great. You just can't use it to its full capacity with the external thermostat. Taking that into account it's actually extremely overpriced.

Works flawlessly. Had it in my 5x10 grow tent work so well I got one for my 4x8 tent. The temperature gauge was surprisingly pretty accurate. For the price you’re getting a strong solid heater. It’s compact but powerful. Good bang for buck.

This heater has met all my expectations and has been working so far. It's only been installed for about a week, but my greenhouse has been staying at a steady 64 degrees and it is not insulated at all. Our outside temp at night has been down to 9 degrees and a little lower but the greenhouse still is able to keep the temp I want my seedlings at. The heater is small but mighty.

Heater works great. Purchased for a MD greenhouse. Thermostat not so good, burned up after a season of use.

While the little heater worked ok, the thermostat Died almost immediately. In fact, the first freeze! So, yes, I lost plants and had a lot of damaged ones in my small greenhouse. It became a heater on a timer, rather than a thermostat. I had to do another temp monitoring set up.

I purchased this to heat a 'pop-up' greenhouse that's 8x12, so 96sqft. With this thing on high, I was not able to get above 52 degrees. Granted, I really only need it to stay above 40 degrees, so I set 45 as the target temperature, and have been monitoring to see if it kicks off on its own, and starts up on its own (other reviews say the thermostat sucks). So far, it is behaving as expected, it will kick on when the temperature drops to about 39 degrees, and will heat until approximately 48 degrees before it kicks off. I know the heat loss, and inability to climb over 52 degrees on a cold night is likely the pop up greenhouse itself, as the windows are definitely not 'sealable' and have openings between the Velcro spots where air can freely escape. When the daytime highs start to drop, I'll tape those up and make sure to snug up all sidings under the foam tile floor and screw it down to the deck, hoping this will help with heat loss and allow the greenhouse to heat up a bit faster and not use the heater as frequently.*UPDATE*Welp, other people seem to have been right about the quality of the thermostat. Mine just completely stopped working today, nothing else on the surge protector turned off, and the surge protector itself didn't switch, just the thermostat completely dead. The heater itself still works, but now no thermostat besides the dial on the top. I am getting a replacement, and if the replacement has an issue as well I will be returning for money back and adjusting to 1 star. Really hoping this next one stays working.**Update 2**Second unit came in, exact same problem happened in just about the exact same amount of time. This thermostat is complete garbage, I highly recommend looking for something else as I will be requesting a refund and trying out a different heater for my greenhouse.

After researching heaters for my new greenhouse, I decided this was the best option for quality and price. I had some reservations, as several reviews said the thermostat burns out quickly, but I decided to take a chance. After reading the manual for the "greenhouse heater," 2 things stood out to me. It warns not to operate in a humid environment, which is the definition of a greenhouse. And the thermostat is made for their heat mat, which I would assume uses a lot less electricity, though it does say it's compatible with other products. So already I have lost a little confidence in this product. My greenhouse is only 5x6, so i have the thermostat set to 50, and i only turn the heater to level 1, which is the 750watt setting. (I live in zone 7 where it usually drops into the 20s at night this time of year.) The manual recommends leaving the fan setting at max, though i have no idea why. I have had it running 2 nights now, and though I've gotten hardly any sleep from checking on it so often, so far so good! I also have it sitting on the bottom shelf of a metal table to protect it from any moisture dripping, so hopefully all these precautions will extend the life of my thermostat. I'd hate to wake up and have all my plants frozen!