Filling loop valve left open by guests

[Davie77]

I had some nightmare Airbnb guests - two young lads. They came home drunk on their first night and phoned me at 11pm saying the heating wasn't working (it was fine).

I'm an hour's drive away.

They had turned the wrong dial and instead of turning from 'off' , via 'timer', to 'on', they turned from 'winter', via 'summer' to 'maintenance'; which switched the heating off - though the hot water was still working.
Being an hour's drive away and at 11pm at night I wasn't about to drive over so I asked them to send a photo of the dials and as I had suspected they'd turned the wrong one. I explained to the drunken dumb-ass how to switch it to the little snowflake which he did and said all sorted.

4 days later I come home and see they've left the place like a pig sty with muck and rubbish everywhere. The heating seemed to be working but pressure needle in red and temperature very high.

On checking they had opened the filling loop valve and left it open (inline with the pipe). Possibly for 4 days! (and these guys were supposed to be engineers!). I immediately closed the valve (there is only one on my system and it's not actually on a 'loop' - just the pipe) and bled the radiators to get the pressure back in the normal zone.

What damage is likely to have been done?
Any advice appreciated

 

[Deleted member 267285]

It might have activated the pressure relief valve being that pressure, which can make it weak or it might not re-seat, therefore the pressure may drop. This could be confirmed by checking the discharge pipe (copper pipe leading to outside).

 

[Harry Bloomfield]

About all you can do is carefully monitor the pressure, and see if there is any drop, which will indicate there are leaks.

 

[Davie77]

Thanks
So if the discharge pipe outside is dripping that means the pressure relief valve has not re-seated properly?
And that will cause the pressure to drop over time?

How difficult/expensive a fix is it if this is the case?

 

[muggles]

May be worth blocking access to the boiler and getting a WiFi heating controller you can turn on and off yourself?

 

[Deleted member 267285]

Not necessarily, as I said it could just be weak. Depending on the boiler make and model, location and engineer will depend on cost.

 

[martygturner]

That depends if the boiler is on or not and where the prv is connected too...most are plumped in to the condensate drain, so if the boiler is on you will see drip drip.

I would leave it for a week, they crud themselves up fairly regularly, just like a wee leak on a rad.

If you have to replace prv valve its not ( boiler dependant) a difficult job nor are the parts expensive think sub £25...it all depends where the manufacture has shoved the thing.

 

[Davie77]

Great thanks all

I love that they 'crud themselves up' ... bring on the crudding!

 

[Davie77]

One other thing, when I open the filling valve usually I could always hear the water gushing through and the pressure guage needle needle moves quickly up. So it takes just a couple of seconds.
Now I don't hear anything and the needle only moves a little then stops. I just noticed this after bleeding the radiators and then attempting to check that the filling valve still worked.

Why would this be different from before?

 

[Mottie]

They may have diluted your system inhibitor. May need replacing if so.

 

[Deleted member 267285]

One other thing, when I open the filling valve usually I could always hear the water gushing through and the pressure guage needle needle moves quickly up. So it takes just a couple of seconds.
Now I don't hear anything and the needle only moves a little then stops. I just noticed this after bleeding the radiators and then attempting to check that the filling valve still worked.

Why would this be different from before?

Could be the filling loop isn’t opening fully, or there‘s a blockage in the pressure gauge tube/feed.

 

[Davie77]

Could be the filling loop isn’t opening fully, or there‘s a blockage in the pressure gauge tube/feed.

Would that have been caused by this incident? Seemed to be fine before.

 

[Deleted member 267285]

Would that have been caused by this incident? Seemed to be fine before.

Not normally for the loop as that would be wear & tear. Could have disturbed debris if the system isn’t clean.

 

[martygturner]

Have you got a pressure reducing valve fitted just before the filling loop, lots boilers do and are set at 2.5/3 bar ish...

 

[Davie77]

Oh I don't know. Good question. There is no loop as such. Just one valve on the in-pipe