Weather Station Thermometer Shield


This is the modified Stevenson Screen/Radiation Shield I made for the La Crosse WS-2316 Weather Station Thermo-Hygro Sensor.  After I had initially mounted the Thermo-Hygro Sensor to the side of the house, I kept receiving false temperature readings for the 3 hours in the morning that it was in direct sunlight.  I wanted to build something inexpensive that would act as a radiation shield, so I modified a vent screen and constructed a modififed Stevenson Screen.  I didn't have a bird house in mind originally, but the final product essentially looks like one (hopefully the birds don't notice and try to use it!).  Still, for about $6.00 in parts at Home Depot, functionality wins out over aesthetics!

Weather Station Shield Construction

(click on any image for larger size)

 

 

The concept was to construct a radiation sheild similar to a Stevenson Screen that would hang from a second story eave away from the siding.  It needed to be small, light weight, and well vented (since I didn't plan on adding an aspirating fan).  Cheap would be a bonus.  Solution:  a modified 8" x 18" vent screen bent to fit a 1" x 6".    Vent: $2.69.  1" x 6" x 8': $2.98.   Success:  Priceless!

Initial phase of cutting out the necessary pieces.   All from the same 1" x 6".  I could have made the unit more elaborate by mitering the roof joint or squaring off the roof line, but the shield was simply for functionality, not for selling at a Farmer's Market.  I originally thought I would use the small vertical board in the middle to mount the Thermo-Hygro sensor to, but the TH Sensor already has its own mount to separate it from the rear board and adding the additional mounting board would have put the sensor closer to the front of the vent than I wanted.

I sanded, primed, and painted the radiation shield (clearly now - inadvertantly - a weather "bird box").  Additionally, I added some ventilation holes in the triangular piece as well as in the base and attached screen mesh over the holes to prevent bees or other insects from crawling in and making my bird box their home.  I attached the pieces with wood glue and nails, and later caulked some of the joints.  Here you can also see that I added extra ventilation holes in the Thermo-Hygro Sensor (2310-TH) that did not come from the factory.  I also added several in the back of the Sensor too.  The circuit board is directly behind the new holes, so I had to disassemble the housing first (easy - 4 screws) prior to drilling.  I also left the rain protection cover off since it would be sheltered by the "bird box."

At this point in the construction, I also realized I would need access to attach the wires to the TH Sensor and potential access for maintenance.  I had originally intended to access it by just unscrewing the mounting screws, but at about 20' off the ground, that's a bit difficult.  Instead, I cut slits up the side of the vent (see next pic) and used wires to tighten it down with.  This provides easy access in the future without having to dismantle the vent screen and it still keeps out bugs.

Here, the slits to make an access panel are clearly seen, along with the tie down wires.  Also, the 9 holes in the base can be seen as well.  I originally had also thought about keeping a 1/4" gap, or so, between the roof and the vent on the sides to allow for extra ventillation, but decided against that since I had already added the extra ventilation holes and the gap would only allow bugs inside the unit.  Hidden from view in all of these pictures is the hole for the wiring.  I drilled a 3/8" hole just below the bottom of the base unit at a downward angle (from inside to out) so that any water that might run down the back side of the board or wires (which are tacked down on the back side of the board) would not drip inside the unit.

Finally!  The unit is up!  I used a 24' extension ladder to carefully carry and mount the unit from the eave.  I drilled pilot holes in the 1" x 6" (at an angle so that I could still fit the cordless drill between the siding and the screws) and sank three screws into the trim board off the eave to mount it securely (mounting it to the trim board also helps keep it away from heat directly radiating off the siding).  I bent down the top 10 or so of the louvers a little bit to be sure that there wouldn't be any direct sunlight hitting the sensor.  The unit is mounted on the East side of the house (North is ideal, but I couldn't run the wires that far and it could potentially receive direct sun for about 3 hours in the morning that could cause inaccurate temperature spikes - hence the need for the radiation shield!).  Success!  The temperature spikes are gone!

The wind sensor (TX20U) with wind gauge and anemometer, and rain gauge (2310-Rain), mounted on the side of the house and positioned about 6' above the roof line.  I mounted it on a wooden pole that provides rigidity (PVC too flexible and not recommended) while not creating a lighting rod at the same time!  As you can see by the view (and pics below), the sensors are nearly unobstructed (just a few trees 1/4  mile away or more).  We are at the crest of a hill in Hazel Dell at 300' elevation.

View from the top of our roof to the Southwest looking towards downtown Vancouver (Washington), the Columbia River, and the West Hills of Portland, Oregon.

View to the Southeast with Mt. Hood and the Cascade Mountain foothills in the background (click on the image for a larger picture).  Mt. Hood is about 40 miles, as the crow flies.