Greenhouse construction

Let's hope so! Pathetic as it is...i'm still 'in process'. There is now electricity and the inside has been painted bright white and the cedar beams have been sealed. I did buy the heater which is currently sitting in my living room. Hopefully i'll get it hooked up this weekend.

The last few things that remain to be done are: some caulking here and there, installing the heater, and figuring out the watering situation. But i'll probably start moving in shelves and plants while figuring out the watering. So i'm close. Stay tuned.

Here's an interesting issue that came up. I had two vents installed with motorized openers which are controlled by a thermostat. The thermostat has a range of something like 40 degrees up to 100 or more. Since there is no heater yet, when it got cold the thermostat would trigger the vents to open. That wouldn't really be such a big deal since there are no plants in there yet. But....one of the motors seems to be jacked up in some way (that i can't figure out) such that when it starts opening the vent it just keeps running endlessly until the temperature gets high enough to trigger the thermostat again. And that can be days on end. So the motor basically has spent the better part of the last month running almost continuously. I'm literally shocked that it hasn't burnt out (last time i checked). I guess the morale to the story is either ...don't install things that are controlled by a thermostat until you can maintain a stable temperature, or, those motors are pieces of crap! Or both.

 

The heater is a Southern Burner non-vented type. The factory is just about 45 minutes from my house which was quite convenient.

The motors are made by Multiproducts. I bought them from either Growers Supply or Greenhouse megastore. I don't think the motor running all the time is necessarily the fault of the motor itself but rather the fact that i don't have a heater going yet so the ambient temperature can fall below ~40 degrees, which is the lowest set point on the thermostat. Under 'normal' conditions, say when it is hot outside, I would have the thermostat set on around 70 and the motors would click on at that temperature and open the vents. In retrospect I should have had an on/off switch installed when I had the thermostat wired in. And I can't close the circuit because it is one of the circuits that runs part of my house.

The real problem with the motors is that they operate by turning a spindle to which is attached an arm. The way the arm attaches to the spindle makes it impossible (illogical?) for the arm to actuate without running into the housing on the motor on the downswing. And the instructions specifically say to ensure that the arm does not hit that part of the motor. It looks like it was specifically designed for the motor housing to limit the movement of the arm so that it will swing in an arc just enough to open the vents and then stop. But that would be in complete disagreement with the instructions. So either the instructions are crap (clearly true), or the motors are not designed properly (possibly also true). The only way to install the arm on the spindle in agreement with the instructions would be if the spindle was about an inch longer. As it is, installing the arm so that it does not impinge on the housing requires you to attach the arm to the last millimeter or two of the spindle, and that makes the arm unstable.

In addition to all that (which probably makes no sense unless you can actually see it installed and/or view a diagram of the way the motor works), the first motor that arrived had crimped wires and one of the wires was actually cut through. Lastly, the electrician said that the wires were not long enough and had to install a junction box underneath each motor. Long story short ....i do *not* recommend using this type of motor for vent opening.

 

It is not easy to explain.

The thermostat has a range of about 40 degrees F. up to around 100 degrees. If I set it on around 70 or so, the vents will open when that temperature is reached. Since I really don't want the vents to open at this time of year, i turned the dial on the thermostat to its lowest setting. But that means when that (low) temperature is reached, the vents open. And when the temperature stays at that low temp., or goes lower, the motor keeps running on one vent until it warms up hotter than the set point, which was days on end a few weeks ago when it was cold.

Now that it is warm again, the temperature is not going lower than the lowest set point and so the vents are not opening/motors are not running.

Robin posted a pic of the same type of motors so you can see the arm attached to the spindle that i was talking about. His are installed upside down. I would say that's a sign that something is 'trouble' when you have to install it upside down.