Leak in the airing cupboard

[onlyfoolsanddonkeys]

I went to get some bedding out of the airing cupboard yesterday and it was soaking wet. This was on the first shelf just on the right side where all the pipe work is, the second shelf above was dry. No obvious sign of a leak. Had a shower and heating on since. I have a towel where the leak was and no signs of water. Plumber coming round next week. Any ideas? It seems like someone has chucked a bucket of water over the bedding. Must have happened in the last week as do the bedding weekly.
-It's a conventional heating system with a water tank in the loft
-the airing cupboard is in the dining room ground floor
-The bathroom is above it

Perhaps put some paper or a tray on top of the towel so that it is easier to spot any water that leaks again.

A photo of the setup might help in the meantime.

Well normally the airing bit of the airing cupboard is above all the pipework.

Where did it feel most damp on the clothes, on the top, in which case the leak came down from the bathroom or the bottom in which case it came up rfom the water tank ?

Is there any ceiling damage to indicatate water came down from the bathroom above ?

Water cylinders do sometimes have overflows and pressure release valves depending on type. It's possible that an overflow activated and dumped water in the airing cupboard. But you need to investigate how that may have led to your washing being soaked.

The fact that it is transient (I assume you cannot find any water source now) might indicate that it is due to a relief valve, or maybe some human action. So for example maybe someone took a rare bath rather than a shower and there is a problem with the waste pipe. But you should be able to trace some path of how the water got into the clothes.

I have just moved the towels and the underneath is wet but not on top. I put a sink bowl in there now. The gap in the first shelf is where the water is. Thanks

Hard to see from those pics because the resolution is too low but it all looks a bit spaghettified underneath that area below the gap where your towels were.

Maybe there is a pressure release valve underneath there that blew.

I have one on my system, it is at the top of the DHW/CH loop. That does look like the kind of area it would be on your system. If it released it would blast air and maybe water upwards onto your bottom shelf.

So possibly could be an expansion tank failure in the boiler ? This is pretty common.

Don't know for sure though.

Was the water that soaked the towels clean or dirty ?

Water out the heating loop is often dirty, grey or black. Or stinks because of the inhibitor in it.

if it comes out of your cold water or hot water lines it will be cleaner of course.

Thanks. The bedding was clear water and didn't smell.
I did leave the basin tap on, last week I think so could fit in the theory of human error.
I had a new boiler fitted in January so I am hoping it's nothing to do with that.
Can't see a pressure valve under the tank.
Agree, it's spaghetti junction!

@GasPanic one more photo!

I would wait for the engineer to be honest.

If the water was clear then maybe it came from the top. Hard to see how it got there though without soaking the top shelf though.

I would be very careful poking around there if it is still wet. Water and electrics don't mix and there is a fair amount of electric stuff in that general area.

@GasPanic thanks. I will leave it to the professionals. I have already called a plumber.

Did you get an answer to this ? Same here the first two rows are soaking wet . But the roof is also wet .