Pool roof heating leaking air+water

[Maya]

Hello,

We have bought a house recently that came with a (working) pool. (When I say « we bought » , I mean we took a loan). The only thing we knew about pools was how to swim in them
A few days ago, after months and months of no problems whatsoever, there were bubbles in the pool when roof heating is on, and there is a place (a part of a vacuum relief valve ?) where there is at first air coming out (hissing) and then soon afterwards water.

Our pool is small (6x8m) and it has a sand filter. I’m posting a few photos and would very much appreciate any ideas you might have concerning our problem. I've marked in red where the air and water are coming from.

Pool maintenance firms are nonexistent here where we live (beautiful French countryside, sadly stricken with depopulation) and pool got to be my “area of expertise”, since my husband is dealing with other maintenance problems (including runaway cows and sheep .

Could it be that our sand filter is dirty and that the water pressure is too low for the vacuum relief valve to close? Currently it is slightly above 0,6 bar. We change the pressure gauge about a month ago.

Thank you all for your help!

[Teapot]

What part of France are you in?
Was the system drained over winter?
If not it's a replacement part as it has probably split.

[Maya]

What part of France are you in?
Was the system drained over winter?
If not it's a replacement part as it has probably split.

Thank you for your reply!
Yes the system was drained. When we restarted the system everything worked fine, roof heating included. There were no bubbles or air/water leaking.

I didn't quite get what you mean by this: "If not it's a replacement part as it has probably split."

[Teapot]

If not drained down and system froze over winter something would split with expansion.

The 3 valves on the wall left of the filter are all open so not sure how much water is entering the heating system. If you need to stop the leak to use the pool close the two vertical valves. You may get some water ejected from the safety valve up on the roof.
The part that is leaking just looks like a bung in the end of the pipe run.

[Maya]

If not drained down and system froze over winter something would split with expansion.

The 3 valves on the wall left of the filter are all open so not sure how much water is entering the heating system. If you need to stop the leak to use the pool close the two vertical valves. You may get some water ejected from the safety valve up on the roof.
The part that is leaking just looks like a bung in the end of the pipe run.

Thank you for clearing that up.
It was well drained and it worked for months in the spring and summer without a problem.

The valves you mention, are set for filtering without the heating. That is why they are open they are.

I'm having troubles identifying the part I circled in red. Do you happen to know what it is?

Thanx again!

[Teapot]

I can't see fully the first valve of the set of 3 on the wall to the left of the filter but they all look open.
Valves are open when the handles are in line (parallel ) with the pipe. They are closed when they are at 90deg to the pipe (across) so they look all open passing water into the heating, so not set for filtration. Closing the 2 vertical valves would only allow water to bypass the heating, it's called a bypass loop for this reason.

The part you squared in red, the part that is leaking just looks like a bung in the end of the pipe. It may be that loosening the hose clip you can make the bung fit better.