Solar Collector shutdown but tank cool?

NurseBridie

Solar Panels installed 2008
Collection area 2m2
200litre cylinder

Yesterday the solar panels shut down because it said the temperature had exceeded 144 degrees but the tank was quiet low around 40degrees. I only noticed this issue of the collector emergency shut down last august as it seemed to have been happening frequency then and there was a noise but this has gone now. So got someone in to service and they told me there was nothing wrong, everything was ok and that my anti-freeze was good as well.

So to put my mind at ease my questions are:-
1) Is this normal and why does it shutdown and not continue heating my tank which is quiet cool, this seems a bit silly to shutdown?
2) If the solar is at 144, should my tank not be quiet high?
3) How do I know if my solar is heating my tank effectively as I have been checking temperatures and they seem very slow to rise.

twotontony

Hi, My solar panels are not heating my water for bath, shower, etc. Despite the really warn, sunny days recently, I have had no warm water- never mind hot water.

What could the problem(s) be?

macnab

Do you have a pressure gauge on your system? If the pressure changes a lot then I would suggest that you have an air pocket at the top of the system. The lack of fluid will allow the temperature at the top to go too high which will shut down the system. One cause of this is a non functioning air release valve, or simply a small leak which has allowed fluid to escape.
These problems often only come to light at this time of year as the sun makes a welcome comeback and boilers become redundant.
Either way, keep an eye on the pressure. A fully charged system will have little or no change in pressure.

freddyuk

Check the pump is actually running? If there is air in the system it will be making a noise and possibly not moving any fluid in the circuit. If it is quiet but vibrating it is working correctly. Try adjusting the pump speed knob to check for noise.

Is the flow pipe hot? Be careful as this can be scaldingly hot if working correctly.

Is there a bypass installed? Check the valve is not stuck and the by pass is taking all the heat.

Check your temperature sensors are correctly installed fully into the pockets.

If your system has actually stagnated there may be fluid in the catch tank which needs replacing into the system.

Fluid will not escape from the automatic air release valve (on the panel). This is for commissioning only and is isolated by shut off valve. If the isolating valve is faulty and leaked passed to the air valve then the whole unit may need replacing. If you have a twin line pump station you should have an air separator with a bleed screw which may release any trapped air.

twotontony

Hi, many thanks for the replies.

I don't know much about these systems- just enough not to tamper with them!

I appreciate the knowledge gained here but I will leave the problem to the installer.

I thought it might be something simple like an upset temperature setting or an on-off switch or something simple.

Thank you both for your time and information.

ccsolar

NurseBridie wrote: »

Solar Panels installed 2008
Collection area 2m2
200litre cylinder

Yesterday the solar panels shut down because it said the temperature had exceeded 144 degrees but the tank was quiet low around 40degrees. I only noticed this issue of the collector emergency shut down last august as it seemed to have been happening frequency then and there was a noise but this has gone now. So got someone in to service and they told me there was nothing wrong, everything was ok and that my anti-freeze was good as well.

So to put my mind at ease my questions are:-
1) Is this normal and why does it shutdown and not continue heating my tank which is quiet cool, this seems a bit silly to shutdown?
2) If the solar is at 144, should my tank not be quiet high?
3) How do I know if my solar is heating my tank effectively as I have been checking temperatures and they seem very slow to rise.

Hi
If you hear noise it could be air the system or you could have a leak
Check the pressure gauge very early in the morning for an accurate reading, pointless checking it in the evening as the air within the piping will create pressure when hot but you defiantly need a system flush,
cc

ccsolar

twotontony wrote: »

Hi, My solar panels are not heating my water for bath, shower, etc. Despite the really warn, sunny days recently, I have had no warm water- never mind hot water.

What could the problem(s) be?

Hi
Going by the limited info you have provided I would think that you have 0 pressure from an old leak and this could also have damaged the pump
Check pressure on gauge when it is coldest as this will give you a more accurate reading
you are looking at a system inspection and flush out to fix the problem

cc

twotontony

Hi, thanks for the information.

I am wondering whether to get a plumber to check the system- or is there some other specialist technician that would be more be more suitable for solar panel heating?

It seems to me that not every plumber is familiar with the workings of solar panels.

esox28

Google plumbing solar servicing and your area.