I didn't really think about it much. Now you got me thinking. You can see in the middle of the photo, my thermastat is in the middle of the cukes. Water not an issue, I use drip irrigation.The thermastat was probably shaded by the leaves at times.

{{gwi:289800}}

Eric

If at all possible, don't locate it on an exterior wall. It will demand heat when the rest of your ambient air is sufficiently warm. Then you'll start turning it down to a number you calculate will give the correct set point, and forget to compensate for it. ;-)

I have them set up differently in different houses, but the most accurate one is suspended mid-air from the roof of the house down to bench level in a metal conduit. It's dead-on accurate.

We have out heater thermostat near the heater but out of the direct flow of heat and fairly low (about 24-inches off the floor). Seems to work really well there for us. We have our circulation fan thermostat mounted higher on the house wall, and the heat circulation fan thermostat mounted above our main heater. Our ventilation fan thermostats are mounted with the fans themselves on the ceiling of the GH. Not all optimal, but they're working really well with each ot her across all seasons so why mess with success. Experiment...experiment...experiment....

calliope,

Do you have a photo of your conduit setup? Sounds like it's not adjustable in height. I've read that your thermastat should be located just above the plants. Does that mean it should move up as the plants gain height. What are your thoughts? Does it make that much of a difference?

Eric

No, it's not adjustable in height. It sits about a foot off the top of the bench level. When potted crops are in, it's not an issue, as I place them around the stat, but when bedding plant flats are in, it could be because of watering. Things get tight in there in spring, but just place either shorter flats under it and move them to water, or leave that area open. No, a foot or two isn't that big a deal in a larger greenhouse.

There are so many cold and hot areas in greenhouses the temperatures are really pretty inconsistant from one bench to the next. It can work to your advantage by knowing where these spots are and putting plants who like that environment there. The big thing is to keep the stats low enough they don't catch the rising heat in the peaks, out of direct sunlight if possible, and off cold walls or heater air flow.