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View Full Version : Solar pool systems in TV during freezing weather...


billethkid
11-18-2014, 09:22 AM
If you are new to the area and have solar assisted water heating for pool, spa or other......remember that when temperatures go below 39 degrees the roof panels are subect to freezing and damage. The panels are very thin and exposed high up subject to wind chill effects.

Your manufacturer should have guidelines for turning off the system and by-passing the water circulation to the panels.

WHy 39 degrees? That is what our manufacturer recommends as a cautious temperature to use. And 39 degrees with a slight breeze can easily be down to or below freezing.

If your pool system has an automatic controller it is most likely set to auto cycle the pumps during freezing temperture periods. Check your settings to be sure this feature is in fact enabled. If you do not have a controller on your system turn on all pumps during below freezing temperatures.

Wind chill factors are based on temperature loss on the human face at varying temperatures and climatic conditions like wind. There is a school of thought that suggests inanimate objects like car radiators and such are only affected by the base temperature. Prudent freeze prevention planning would suggest planning on the wind chill temperatures.

Any other winterizing tips (for pools, spas, faucets and plants, etc) used by others are appreciated.

biker1
11-18-2014, 09:35 AM
The wind does not impact the temperature that inanimate objects experience. The wind can increase the rate at which an inanimate object cools to the ambient temperature but if the temperature is 39, no amount of wind will cause the object to experience a temperature below 39. Wind chill does not apply to inanimate objects.

If you are new to the area and have solar assisted water heating for pool, spa or other......remember that when temperatures go below 39 degrees the roof panels are subect to freezing and damage. The panels are very thin and exposed high up subject to wind chill effects.

Your manufacturer should have guidelines for turning off the system and by-passing the water circulation to the panels.

WHy 30 degrees? That is what our manufacturer recommends as a cautious temperature to use. And 39 degrees with a slight breeze can easily be down to or below freezing.

If your pool system has an automatic controller it is most likely set to auto cycle the pumps during freezing temperture periods. Check your settings to be sure this feature is in fact enabled. If you do not have a controller on your system turn on all pumps during below freezing temperatures.

Wind chill factors are based on temperature loss on the human face at varying temperatures and climatic conditions like wind. There is a school of thought that suggests inanimate objects like car radiators and such are only affected by the base temperature. Prudent freeze prevention planning would suggest planning on the wind chill temperatures.

Any other winterizing tips (for pools, spas, faucets and plants, etc) used by others are appreciated.

l2ridehd
11-18-2014, 10:10 AM
Not sure they all are, but mine is designed to drain every night when the pool pump shuts off. The valve switches to close and that opens a by pass that allows all the water to drain off the roof.

billethkid
11-18-2014, 10:11 AM
Thin inanimate VS thick inanimate VS small/thin volume of water VS large volume of water VS moving water VS non moving,etc, etc etc......

Since I am not sure how water may or may not be affected in the equation I tend to use a lower temperature potential as is practical.

TVMayor
11-18-2014, 10:19 AM
I use what is called a "neighborhood pool" it works flawlessly.

biker1
11-18-2014, 10:27 AM
None of that matters. If a surface is wet, evaporative cooling can drop the temperature. Once the water evaporates the surface will warm to the ambient temperature. Since you are talking about a liquid in pipes (and the outside of the pipes is dry), the wind does not matter. Higher wind speeds actually tend to warm things up a bit by mixing down warmer air if an inversion had developed. Use whatever temperatures you like but the physics are clear.


Thin inanimate VS thick inanimate VS small/thin volume of water VS large volume of water VS moving water VS non moving,etc, etc etc......

Since I am not sure how water may or may not be affected in the equation I tend to use a lower temperature potential as is practical.

outlaw
11-18-2014, 10:31 AM
Don't forget to account for nocturnal radiation....

biker1
11-18-2014, 10:50 AM
One scenario to be concerned about is clear, calm nights when the temperature is forecast to be in the mid to upper 30s and the dewpoints are low. The panels surfaces may radiate enough to drop to freezing or below - essentially an inversion develops. If the wind picks up it will help this situation by breaking down the inversion and warming the panels.


None of that matters. If a surface is wet, evaporative cooling can drop the temperature. Once the water evaporates the surface will warm to the ambient temperature. Since you are talking about a liquid in pipes (and the outside of the pipes is dry), the wind does not matter. Higher wind speeds actually tend to warm things up a bit by mixing down warmer air if an inversion had developed. Use whatever temperatures you like but the physics are clear.