Thermostatic valve flew across the room = spontaneous flooding

Hi all. First time poster hoping for some advice please.

On Friday around 10:30am the plasterer we hired to smooth over all our Artex ceilings called to say that when he walked in, he saw the radiator pipe in the living room (top floor) gushing water like a fountain with the thermostatic valve about 10 feet away. (We had removed the radiator in the living room 2 weeks ago and capped it off in order to strip wallpaper and eventually paint.) The plasterer told us he tried to put the valve back on, unsuccessfully, and then called his plumber friend to turn off the water. The water appears to have been flowing for hours. We were in the house at 9pm the previous night and it was fine, but are staying elsewhere for a couple of weeks so we gave the plasterer a key.

In the end we have water damage to the ceilings and walls in three rooms, the hallway, and 3 closets on the bottom floor, damage to the floor in the living room, and the carpets will need to be replaced in all the affected rooms.

I can't seem to find anything on online about any situation where the pressure mysteriously increased like this. All advice is very gladly welcomed. How is it possible for the pressure to build up so much to shoot the thermostatic valve 10 feet across the room? This is a gravity fed system which comes from an expansion tank in the loft, and the heating was off. Why didn't it affect the other two rooms where we'd removed the radiators? And what do we do to make sure this never happens again, since we will be removing radiators to strip wallpaper and paint in other rooms once life returns to normal. Many, many thanks in advance for your help.

I have absolutely no idea, but the first thing I would be doing is talking to the plumber who attended and ask him what he found and how it could happen!
Report his responses back here and we'll see if his reasonings "hold water", so to speak.

It's quite possible for water to have flowed for several hours if the F&E tank supply was not isolated, but for it to blow a TRv and produce a 'fountain'??? - far from likely.

Strange one this, Don't shoot me just some thoughts...
Is it a pressurised system did some one leave the filling loop on? (strange that it completely shot off the TRV, instead of the pressure relief blowing)
Perhaps the TRV was not tight etc.
As we all know most Trv's have a frost protection setting that will completely stop the water flowing through the valve UNLESS the temperature drops?
Was the 'outlet' side of the TRV capped ?

.

Did the valve just slide of the end of the pipe because was not securely fitted to the pipe.

Fitted tight enougth to make a water tight joint but not tight enough to hold the valve in place. Is the olive still on the pipe end ?

The radiator, when in place with the valve connected to it, would have prevented the valve from sliding off the pipe.

Maybe removing the radiator loosed the joint valve to pipe.

Exactly, sounds as if you disturbed a valve which was not tight enough when you removed the radiator.

Your house insurance, if any, will probably cover consequential water damage. But not the original plumbing problem.

Tony

It's a vented system so don't see how trv could have been launched across the room

Only 2 ways this could have happened -

Mechanical influence - it's been physically bumped/removed
Pressure blew it off - On a gravity system the pressure is relatively low and I would have expected a fitting that loose to have shown symptoms when the rad was removed. Certainly don't think there would have been enough pressure to launch a TRV 10 feet tho!

I think we're all suspecting the 'elephant in the room'

Poltergeist?

Madrab said:

don't think there would have been enough pressure to launch a TRV 10 feet tho!

Click to expand...

Maybe it just rolled across the floor.

dilalio said:

first thing I would be doing is talking to the plumber who attended and ask him what he found and how it could happen!

Click to expand...

Did the entire valve come off the pipe? Or did trv head alone come off? If the latter then if its a cheap one the plastic becomes brittle and could possibly become detached, this would then release the pin allowing the water to gush out.
Or maybe the plasterer knocked it.
if the entire valve came off the pipe then it can't of been on properly to begin with.

Thanks all.

I have no idea why we didn't think to ask for the details of the attending plumber when we had the chance; I guess we were too brain-fried from the whole thing. We can't ask now because we let the plasterer go last night. I did speak to the plumber our neighbour uses however (our houses are carbon copies) and yesterday he said he couldn't conceive of any way it was physically possible for the pipe to be gushing like a fountain. "Fountain" was the word used by the plasterer when describing what he saw.

We were told that it was the whole valve which flew off, although it was securely attached when we returned. (Attached to a pipe which angles toward the wall.) We know it was on properly before the leak because we'd run the heat in the house while that particular radiator was not attached and there was no leak from the pipe. It's not possible that it rolled because there were tarps, wrinkled plastic, and bags of plaster between the radiator and where the plasterer said he found it.

The majority of the water damage is right where the plasterer said it was however - in the centre of the room, 10 feet from the radiator. This is also where the plasterer mixed all his plaster.

As to the elephant / poltergeist... It's an awful thing to think about honestly. Probably we'll never really know, although I keep looking for another explanation because it's just so awful.

Living room situated on top floor with water gushing 10ft from open end?...this being an open vented system?
Yea right...........valve found 10ft away from source????
Turn it in FFS......any tell tale signs on ceiling????...
....another troll FFS..