PigletJohn if you're around, help please!

[SealSong]

Hi PigletJohn if you're around.
Please could you give me your thoughts on my boiler which has just gone kaput?
Basically I was just topping up the water pressure via the water pressure valve, it seemed to be topping up ok, got to around 2 bar pressure then the pressure dial went crazy with the dial hand swinging backwards and forwards at high speed from full to half full, with a kind of banging noise but that might just have been the dial going nuts, it was very alarming and clearly a major malfunction of something.
I've switched it all off.
I've left a message for my plumber, waiting for him to (hopefully) call me back.

What does it sound like has happened? Has my boiler potentially died? It's a 10 year old Baxi combi, normally pretty reliable though has an issue with gradual loss of pressure, never had anything like this happen before.

Thank you

I wouldn't be surprised if the pressure release valve had opened and squirted water out of the pipe that goes through the wall behind the boiler.

It will probably drip now, until you get a new valve fitted, because it may have got scale or dirt on the seal. They can be cleaned, but are not expensive to buy.

It's also possible that there is something wrong with the pressure vessel, which absorbs excess pressure (it is pumped up with air like a car tyre) but that would show itself by the pressure gauge going surprisingly high when hot, then surprisingly low when cold.

Try pressurising it to 1.5 and see if it works. PRVs usually open at about 3.

You will probably not be able to tell if the PRV is dripping until daylight.

Thank you. I'll check it out in daylight, if my plumber hasn't been by then.

I'm a bit nervous to try starting the boiler again now, I wouldn't be damaging it further?

Very kind of you to offer your thoughts.

I don't think so.

Could I have caused a problem by turning the PRV the wrong way and filling the system too much? I have a slight feeling that I might have forgotten which way to turn the valve to shut it off and turned it fully open instead leading to it going haywire....

it's possible.

Boiler is sorted! Just had plumber on the phone - I had indeed turned the valve the wrong way and put too much water in. The banging noise was the water being spat out of the pipe to the outside, the boiler has self settled at 2.5 bar and is back on working perfectly. He said that is a common thing that people do in error.

Thanks for your help Piglet.

In future remember lefty loosey, righty tighty (some plumber told me that years ago and always stops me making that mistake)

Glad it's working again

Hah, that's exactly what my plumber said, it's clearly plumber-speak

I'm glad it's working again too, it felt pretty catastrophic at the time not knowing what was going on with the clanging noises! I feel a tad silly now however