proper solar sensor location

I would imagine any near the panels would be best. Most i have seen are within 12" of the panels. You do not wanting it touching the panels but you want it to see the same sunlight that the panels get. If it where touching the panels it could read to high of a temp. If it is placed on a different surface than the panels have it might read to low becuase the surrounding surface may not get as hot as the panels thus not reading what the actual temp of the panels.

Where is the sensor located right now?

skeeter

Hi, I'm looking for advice on this topic please! My sensor is on my pool house roof, but this is quite a long way from the panels and with tree growth obscuring the sun late afternoon it shuts the controller off whilst the panels are still in the sun. I'd like to move the sensor to where the panels are. Its about 70 metres or so but not difficult as I can run the cable along guttering. However, can I cut the two wire cable at it's connection with the controller and add in any 2 wire cable or is some special kind of electrical cable required? Also, is there any reason why a long length such as 70 metres or so would be a problem? Many thanks, Pete

The primary purpose of a pool water temperature controller is to send information about the temperature difference between the bulk pool water and that of the water in the collectors. Somewhat simplistically, the idea is to have the pump circulating pool water through the collectors when, and for as long as, the water in the collectors is warmer than the pool water (and note, usually by only a few degrees or less when operating normally). Other or less suited locations for meeting that goal will thwart that purpose.

The controller usually/commonly has 2 sensors. One at or in the pool, in good thermal contact with the water in a place that has good circulation and where the local water temp. that's sensed is mostly representative of the bulk pool temp. The other sensor is, or ought to be located in a place and in such a way that it has good thermal contact with the water (or at least the collectors) where it can (somewhat) reliably determine the water temp. in the collectors. Usually, but not always, that's a place near the collectors outlet.

Sensors located in places where they cannot sense, or cannot do a good (that is, reasonably accurate and reliable) job of sensing the (relative) temperatures of the water cannot do their job, and as a result, probably won't heat the pool water as effectively - or at all - as intended.

Reads like your sensors are not in the best locations.

Check/fish around websites for pool water solar collectors for more information.

Hello, I have moved into a house four years ago which has a pool solar panel setup. I just had to replace my shingle roof and then had new panels installed. They company that came out to install the new panels didn't have to touch the filtration system or valves etc. because everything was already there from the previous system, except for the temperature sensor from the solar panels. So, for my question. The temperature sensor that is for the solar was previously attached to the outside of the pipe (did not penetrate the pipe) on the roof. When the solar panel company installed the new panels, they took this temperature and applied the same adhesive they used to secure the panels to the roof and essentially glued the temp sensor to a shingle right next to the pipe. Since both setups (old system and the new panel setup) have this temp sensor on the roof and not penetrating the pipe, I presume this is correct? I'm asking this because the automatic valve to turn the valve for the solar panels isn't automatically switching anymore... I flip the switch on the control box and the valve moves to route water to the panels, but when I flip it back to auto the valve shut off the panels even if I set the temp on the control box to max temp (105F).

The sensor that was moved should be attached to the water return line as it was before. If I understand what you've written, in its current location it's sensing the temp. of a shingle which, when the sun is shining is probably a lot hotter and in any case, most likely different than the pipe temp.

After correcting the sensor location, the system should be checked for other things that new panels and perhaps some piping changes may have changed with respect to different system characteristics that may require some sensor adjustment. Be sure to get good thermal contact between the sensor and the water pipe before checking final system operation. Thermal grease under a clamp and aluminum tape (NOT duct tape) over the clamped sensor seems to work well in my experience in such things.

If your sensors are not triggering the pump properly, besides verifying they are in the right place, check the wires along the way. I had a mice eat one of the wires once, and it took me a while to figure out what was going on...